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Root Trainers - Torpedo pots - Kruger Industries

Root Trainers

Root trainers – Torpedo pots

All about Root Trainers for trees!

The trends of cultivation are changing with the seasons, from traditional agriculture to streamlined urban agronomy. Industrial and commercial cultivation is making novel advancements. Commercial agriculture has also witnessed various trends.
The most common and powerful ingredients for growing plants are sunlight, water, and soil. The way the soil is held together for cultivation has evolved over the years. From old-style pots to poly bags now, the trend is moving to root trainers. They need infrastructure that is scalable, efficient, and cost-effective; hence they are always pursuing new technologies.

The essential ingredients for growing plants are sunlight, water, and soil. One of the simplest yet effective apparatuses developed in recent times is root trainers. They have a wide set of applications. Anyone in root trainer gardening can reap the profits of root trainers. They are also scalable, making them highly sought after by nurseries and plantations.

What do root trainers mean?

The term root trainer was established for a container used as an aid to cultivate young plants and trees in nurseries. The pot is designed as a long tubular structure with a small diameter compared to the stem. There is a drainage hole at the bottom to ensure irrigation. The young plant roots spread up to the narrow walls and continue downwards rapidly growing more roots. The tubular pot is also popularly known as torpedo pot (due to its looking like one!). These are placed in a frame to hold them together.

As a result of this, the primary roots grow stronger. These factors contribute to the proliferation of lateral roots. The root trainers are typical cylindrical containers designed with opaque materials. The tapered design ensures the roots develop effectively.
The key to cultivating healthy plants is having a strong root system. It can nourish and anchor the plants as they grow.

Hence, root trainers are specifically designed to promote healthier and faster root growth. They work well with all seeds and cuttings, including vegetables, flowers, bushes, or tall trees. The use of individual grooved cells yields a higher rate of germination, and the open-ended design is a part of the air-pruning mechanism. It is crucial in eradicating root balling and pop-banned plants. Therefore, root trainers are a must-have for professionals and home gardeners alike— and many root trainers for sale are available in the market.

Often plants are damaged from a root shock when they are shifted to a garden or any outdoor soil. Root trainers can be an upshot solution for such kinds of problems. As the grooves inside the root trainer container dictate, the roots grow straight down, preventing the plant’s root to bind in the container.

The structure of the root trainer can be described as a tall and tapering container. The long trainer provides enough space for plant roots to grow downward accurately into the soil before the transplant. The container is designed so that it is wider at the top and extends narrower at the bottom for the roots to accommodate comfortably. The hole at the root trainer’s bottom helps the excess water to drain out of the container with ease. Specifically, this hole allows air pruning at the bottom effectively.

When the root is exposed to the air, it stops growing naturally. This phenomenon is known as air-pruning. The side roots then start developing much more than usual. This results in a super root system, perfect for any plant. In ordinary pots and seed trays, the roots grow in all directions. On reaching the edge of containers, they tangle up. These tangled knot balls can cause root shock if unattended. They risk plant damage by arresting its growth.

Air pruning is considered nature’s way of alerting the plant roots that they have reached the essential height and stopped growing as they encounter the air outside. Air pruning boosts the plant, which helps in new root growth in another place that leads to a thicker growth system, resulting in a strong, healthy plant. This supports a better transplantation method as the plant can absorb more water and nutrients from the soil for optimal survival and better growth standards.

How to use a root trainer?

  • For your root trainer, first, settle on the height, method, and material. This would rely on the plants you wish to grow, and when you want them to be transplanted.
  • You may build or purchase your own root trainers’ package, complete with accessories such as root trainer trays, and holders.
  • First, pick a growing medium. This would rely on what you’re trying to grow, so there is no one-size-fits-all solution situation. Carrots, for instance, prefer sandy soil, which drains well and is free from obstructions.
  • With a thicker potting mix that preserves moisture, other plants that require more moisture might do better.
  • You’ll need to plant your seeds after you’ve filled the root trainer with a rising medium such as soil or potting mix.
  • Pay attention to the optimum temperature for germination and keep them warm enough before they start sprouting.
  • You may need to provide light for the seedlings after germination. Use a grow light or put them near a windowsill to get natural light. They would also require daily watering to keep them well hydrated.
  • Finally, when you want to transplant the seedlings into the greenhouse, you will need to extract them from the root trainer or larger pots.

Procedure to set up root trainers

After assembling the books of cells, lightly dampen them. Proceed to fill using multi-purpose compost and brush off excess soil. Ensure that the tops of the cells are exposed. Add a little water using a watering can before planting. The rapid root trainer has shallow cells designed specifically for salads, herbs, and bedding plants. The deep-root trainer is better suited for deeper-rooted plants such as sweet peas, fruits, and vegetables.

For large seeds, use one cell per seed while smaller seeds can be grouped into a cell. Then push the seeds down to the correct depth. Brush the compost over to cover the seeds and finish the setup by placing the appropriate lid. The lid should be removed after the first few days. By then, seedlings should begin to emerge. Water the seedlings by standing the root trainer in the half-filled lid for a few minutes. An alternative is using an atomiser to spray. The ribbed cell walls guide the first roots. They stimulate the roots to grow directly downwards towards the drainage hole. 

Root trainer plants are more affordable and advantageous than polybag plants. These plants are raised in cups made of polypropylene. The root trainers ensure the roots grow in the desired direction. The hole at the tapering end of the cup enables adequate aeration and drainage. They also help prevent circular growth.

Cups with a volume of 600 cubic centimetres and lengths up to 25 centimetres are used for planting green budded stumps. Simultaneously, cups of 800 cubic centimetres with 30 centimetres in length are used for brown budded stumps. Coir pith mixture is the supporting medium used for filling the cups, and some root-inhibiting organic chemicals are present in the pith. They are to be removed by immersing the pith in water for at least two months.

Soil is mixed with partly dried cattle dung in equal proportions and can be used as an alternative to coir pith. Green bitter stumps are preferred for planting in root trainer cups. Budded stumps can also be developed from seedlings raised in the cups. The root trainers are then tagged by pushing the cups into a raised bed of soil. Ensure that less than half of the cup is covered in soil. Take care not to clog the drainage hole of the cup. Budded stumps can also be planted after fixing the filled cups in the soil. Watering should be done daily during the initial period. 

Once the leaves get matured, the watering routine can be shifted to alternate days. Care should be taken to avoid the stagnation of water. After the plants develop leaves, they can be stacked onto the racks. The cups should remain suspended in the air for a minimum period of one month. Fertilisers can be used once a week. Use 1% NPK mg 10:10 for 1.5 mixtures in the specific amount of water used for irrigation.

The taproot undergoes natural air pruning at the drainage hole. Thus, the plants get hardened and resume excellent growth on planting in the field. In nurseries, budded stems are planted in the root trainer cups and then tagged in specially prepared stands inside greenhouses or poly houses. Regular manuring and watering are to be carried out, as stated earlier.

The principles of root trainer technology

It provides a suitable environment to reach quick primary and subsequently secondary root development. It includes a tap root and secondary root system to attain compelled multiple taproots. The procedure focuses on maintaining an acute angle of secondary and tertiary root tips. The successive pruning keeps the downward movement of root tips to attain a bunch of roots.
A seedling’s root grows till the end of the root trainer pot, and they quickly dry out and drop off once they exit the pot. This boosts rapid and healthier root growth from the seedling without cutting off the dried parts.

As commonly observed in traditional pots, the root spirals cause problems. When these seedlings are transplanted, the roots continue to intertwine and bundle. This poses difficulties as the roots grow in a circular direction. Circular growth makes it problematic for the plant to find its nutrients. It also impacts the stability of the plant. The root trainer pot provides an effective solution by correcting the seedlings’ root shape from the beginning. It enforces the roots to grow long, straight, and dense. Such kinds of seedlings are better prepared to be transplanted than traditionally grown seedlings.

Precautions to follow for root trainers

  • Root trainer pots usually need more supervision.
  • The roots in these pots dry out rapidly. Hence, they require watering daily. Selecting soil that holds the water well will prove effective.
  • The bottom of the root trainer pots being open results in water evaporating simultaneously from both the top and bottom.
  • Secondly, if the trainer is placed on a solid surface, it becomes impossible to air pruning. Therefore, they need to be placed on specially designed racks only.

Advantages of Root Trainers

  • They need a smaller area/space for planting production.
  • They need a smaller volume of medium for potting.
  • They’re well-ventilated.
  • They permit aerial root pruning.
  • They greatly enable the development of lateral/adventitious.
  • Plants of desirable, vigorous, healthy roots are established.
  • On planting, the planting stock is developed earlier.
  • The percentage of survival and growth rates are higher in the field
  • They create planting stock of homogeneous and superior quality.
  • The productivity of the plantations would improve with the value.
  • They are quick to manage ergonomically.
  • They are repeatedly used, and they are robust.
  • The cost of a medium for potting, weeding, watering, and transportation is lesser.
  • They are eminently suitable for the development of large-scale planting programs and seedlings.
  • Root progress can be seen by gently opening the book.
  • The roots grown are densely fibrous and unbound.

Importance of root trainers

  • The root trainer’s design encourages the roots to grow straight down deep into the soil as they can access more nutrients found deep in the soil, and there are chances to reduce the tangle of roots between two plants.
  • The competition between plants for water and nutrients is avoided. If the roots encounter resistance from the container’s edge, they change their direction and re-root themselves towards the bottom.
  • The most commonly encountered problem during the transplant process is the roots’ damage and little chance of plant survival. Therefore, a strong straight root system helps remove the plant from the container while avoiding cutting roots.
  • The plant roots reach the hole in the bottom of the container as they perfectly grow straight down towards the root trainer’s bottom. At this stage, the ends of the roots stop growing as they cannot draw water and nutrients because of the soil’s absence. Likewise, the roots which are exposed to the air dehydrate due to lack of water. The plant starts to grow roots on the other sides after the air-pruning stage. This leads to a stronger and thicker root system for the plant to survive in transplantation elsewhere.

Disadvantages of Root Trainers

Root trainers are no exception from having disadvantages, despite being a better way of growing plants. There are certain disadvantages where growers need to be more cautious.

  • The main obstacle encountered is that the water drains out fast. This is because of the shape of the root container and the hole present at the bottom. This requires careful monitoring to avoid overwatering and underwatering. Attention is utmost required to keep the soil moist all the time, especially during the germination phase.
  • For the root trainers to work efficiently, it requires an amount or a rack. The shape of the many root trainers does not support standing on their own.
  • The hole present at the bottom of the root trainer needs to be exposed to air at all times. This needs to be ensured so air pruning of the roots will occur. Hence, these trainers cannot be placed on solid surfaces. Special racks need to be used to suspend and stack multiple root trainers.

Types of Root trainers

The following list contains in-market root trainers’ bulk help the clients on a large scale, in accordance with the demand.

Rapid Root trainers:

The Rapid Root Trainers are ideally suited for shrubs and herbaceous plants, as well as for potting. Typically, these are used for all bedding, salads, herbs, and container plants. This size is particularly preferred for cuttings. There are approximately 32 to 35 cells per tray.

  • 32 reusable cells, 3 inches deep, with tray holding and lid propagating.
  • Produces a quicker root formation without root balls.

Perfectly suited for:

  • Bed plants- for example, Bizzie Lizzies, Antirrhinums, Begonias, Lobelia
  • Softwood Cuts- for example, Chrysanthemums, Fuchsias, Geraniums, Heathers
  • Salad plants-for example, Radish, Lettuce, Tomatoes

Deep Root trainers:

The Deep Root Trainers are built with an exclusive book-like system. These root trainers are appropriate for trees with broad leaves or conifers that have a long cycle.

  • 32 reusable cells, 5 inches deep, with tray holding and lid propagating.
  • Develop the roots deep and straight without root balls.
  • Especially vivid for sweet peas and runner beans, and all deep-rooted flowers, fruits, and root trainers for vegetables are in high demand.

Perfectly suited for the plants such as:

  • Small Shrubs
  • Herbaceous plants
  • Bedding plant sheets
  • Sweet peas
  • Fruit plants with broad leaves
  • Broad Beans, French Beans, Runner Beans
  • Sweetcorn, Sunflowers, and Sweet Peas

Compact Root trainers:

The Compact Root Trainers are generally smaller in size compared to the original root trainers. The books of these trainers are placed in their respective slots, giving more space for pants. These containers are claimed to be the most user-friendly with all the features incorporated. Compact root trainers provide all the benefits in just half of the space required. Approximately – 20 cells per tray.

Perfectly suited for:

  • A small number of seeds
  • Around 20 cells per set can still aid in growing sunflowers, beans, sweet peas, and more.
  • Bedding plants, salads, herbs, and cuttings

Slim Root trainers:

The Slim Root Trainers are narrower in size and shape, likened to the other root trainers. Approximately – 50 cells per tray.

Perfectly suited for:

  • Narrow-leafed plants
  • Conifers
  • Leeks
  • Asparagus
  • Onions

Maxi Root trainers:

The Max Root Trainer is considered to be the largest module of the root trainers. These are essentially used for growing long-cycled plants. The plants are grown in dry places, and the larger-sized plants are mostly cultivated.

  • 40 reusable cells, 7.8 inches deep, with a tray holding.
  • Produces a quicker formation without root balls.
  • Ideal for trees, shrubs, and award-winning crops.

Perfectly suited for:

  • Broad-leaved trees grown on longer cycles

Plants destined to dry sites

Jumbo Root trainers:

The Jumbo Root Trainers are single-cell book-like root trainers. It has only a single cell.

Perfectly suited for:

  • Trees with broad leaves that are grown on a long cycle.
  • Plants that need less water are usually grown to persuade the roots to mature to deep depths. This keeps the plants powerful in the long run.
  • Plants in regions which are facing scarcity of water.

Torpedo plant pots are designed such that plants develop a strong root system. These contain trays to handle plants, and also individual cells may be removed based on your requirements. The black torpedo pots are designed to meet all the necessities that will last for many years.

The grooves support the plant to direct the roots downwards. The legs are made such that the roots do not contact the ground by holding the drainage hole. Tall Torpedo pots provide excellent air pruning benefits, which give a healthy root system.

Torpedo Pots (root trainers) Kruger Industries

The following list contains root trainers from the 20th century onwards.

Paper containers:

  • Paper pot
  • Stretch-A-Pot

Wood fibre containers:

  • Forestry pellet: moulded peat moss in a mesh made of plastic.
  • Fibre pot: moulded wood pulp

Individual or separate cells in trays:

  • Single-cell system: Low-density for a cell of polyethene, High-Impact, Tray made with polystyrene
  • Supercell: Low-density polyethene
  • Deep pot: cells and tray are High-density polyethene

Book containers:

  • PET or ABS root trainers: polyethene terephthalate or acrylonitrile butadiene styrene
  • Tube packs: polystyrene

Block-like containers:

  • Styro block: polystyrene that has been expanded.
  • Multi-pot seedling tray: polyethene of High-density
  • Container set system: polyethene of High-density
  • Deep groove tray: polyethene
  • Separated seedling tray: polyethene of High-density
  • Planter flats: polystyrene that has been expanded.
  • Eco pot: laminated plastic

Containers for separate seed growth:

  • Tree pot: polyethene of high-density
  • Once cell root trainers: polyethene terephthalate

Miniature containers:

  • Plug system culture: polystyrene that has been expanded.

Tips for using root trainers

The Five-inch rule is the unheard rule for planting root trainer trees for healthier and stronger growth. Prepare your soil well and place the plants with a mature root system in five inches deep ground. There is no need for constant surveillance as the roots are deep enough to endure any weather changes.

Cutting the roots:

The primary reason why root trainers are chosen is because of the feasibility of cutting the roots. Dip the cuttings into a rooting powder. After this, you can insert the cuttings into the cells for growth.

Usage for large seeds:

Press the large seeds such as beans down into the compost gently when used for cultivation.

Large leaves:

Use an alternate cell for large leafy plants. Otherwise, use the Compactor Rapid Root trainers that are specially designed for this purpose. 

 Delicate leafed plants:

Plants like root trainer Sweet peas are fragile in nature. Root trainers are an ideal choice for such plants.

Seedlings when developing:

Remove the lid or take the trays out of the growth medium as soon as seeds emerge from the soil. The Lid of the Root trainers starts to act as the drip tray.

Usage for small seeds:

Seed trays can be used for small seeds and can be used through root trainer sowing to make the process easier. And then can be punctured out into root trainers.

Germination rates:

The seeds grown in root trainers give high germination rates in properly prepared compost.

 Reduced White fly occurrence:

According to a study on brassica, the presence of whiteflies was never observed when root trainers were used for growing.

Use under bench heating:

To promote quicker growth, under-bench heating is used. This facilitates growth without constraining the root system.

Cuttings and Scale of Pot:

Many cuttings benefit from a shorter pot. This enables early air pruning of the root system.

Watering Inside:

Note that proper watering is necessary for the plants and the root trainer seedlings to avoid drying out as the season warms up.

Cuttings of Stem:

It is possible to take stem cuttings during the year, but it is to do best in spring and summer. There is a sure success in any one of the seasons by using The Rooter pot.

Planting Plants for Out Plug:

When planting plug seeds, note that the top of the soil plug is fully protected to allow the plant to sit.

The Water collected:

To water seedlings, water obtained from a water butt should not be used. To encourage the chlorine to dissolve, use tap water that has been standing for a few hours.

House-grown root trainer plants Enjoy the warmth in an aquarium:

Don’t throw the water away from your aquarium. Store it in houseplant bottles and watch it flourish after watering the plants.

Tips for specific plants:

For Tulips and Lilies:

Since they suffer from the same diseases, lilies and tulips can never be planted together in the root trainers.

For Azaleas

Azaleas prefer acidic soil and watering them once in a while with a combination of 2 teaspoons of white vinegar to 2 pints of water is a smart idea.

Comparison of poly bags with root trainers

The containers most widely used in tree nurseries in developed countries are polybags. They are typically made of black polyethene and, at the bottom, have drainage holes. Poly sleeves made from the same material and a continuous roll are sliced, and they have no bottom. They come between 0.3 to 45 litres in varying gauges and sizes. Polybags are readily available in many countries.

With polybags, a common issue is that plant roots appear to expand in spirals once they reach the smooth inner surface. This would eventually lead to plants with reduced growth, low stress, and wind-throw resistance. It also causes early dieback due to root masses or pathogens ensnarled. This is a big downside to the use of synthetic polybags. Poly sleeves make air pruning when placed on raised propagation beds, such as on a thick layer of gravel, due to their open bottom. Owing to the rise in price and material shortages, it is impossible to use them.

Poly sleeves enable air pruning due to their open bottom when placed on raised propagation beds, such as on a thick gravel layer. But in storage, they are less durable since the potting layer will quickly slip out and hurt the roots. Poly sleeves can never be mounted directly on the ground so that the roots will expand into the ground, and when you raise the plants, the main roots will fall off.

Packets or sleeves can crack early and are not very durable. This can be a concern for plants that have a long nursery period. Normally, they are seen only once. For nursery waste control, recycled poly bags and poly sleeves are a concern because they do not degrade and are often burnt, causing significant air pollution.

Disadvantages of using poly bags

  • The plant’s coiled tap root.
  • Weak lateral root generation and its intertwined structure.
  • Weak support for the plants and the resulting poor wind-fastness.
  • Low tolerance for drought as the coiled tap root does not achieve depth.
  • Heavy poly bags are difficult to move inside the field and from the nursery to the field.
  • The high cost of maintenance in the greenhouse for the left-over crops.

Plants produced in root trainer systems, when they are slightly smaller than those from traditional polybags, can plant out. This helps reduce the need for space in the nursery and the expense of transport to the field.

Newspaper article on Belgaum Forest Dept

Compared to polybags, the root trainer has more advantages; on an experiment basis, we will be going with 25,000 seeds from next year; 50 % of the plants will be grown using the root trainer.

Evolution of root trainers

Early trials of forest nursery containers began way back in the 1930s, with India’s ‘Donas’ (leaf cups) and Tar paper pots from the USA. Various materials such as brick jars, containers made of various broad plant leaves, metal tubes, bamboo shoot tubes, bins, frames made of wood, etc have also been used.

In general, these plastic or paper pulp containers have improved the efficiency of growing a healthy root system. These containers demonstrate the efficient preservation and release of nutrients, air, water, temperature and light. They also provide physical and mechanical assistance for stock control and nursery, transportation and planting operations.

Studies have also been undertaken to recognise other variables that affect container choices, such as container availability and expense, familiarity and ease of use, and eco-friendliness. Several workshops on containers used in forest nurseries were organised.

The association of nursery specialists is currently conducting annual meetings in the US to address various issues related to plant development. Even in India, different container-related problems were addressed at conferences.

Beforehand requirements to use root trainers

  • Availability and cost of raw materials:

An appropriate quantity of raw materials should be required to satisfy the criteria to use containers. . The supply of raw materials from various sources must be taken into account and the cost of refining, shipping and maintaining the raw material must be calculated as key considerations to be followed at nurseries or container manufacturing sites.

  • Cost and ease of processing in large-scale manufacturing:

It is necessary to procure containers of the required quantity within the shortest possible period for timely completion, given the seasonal nature of the nursery work. To ensure timely delivery, it should be easy to manufacture containers in large quantities.

  • Facilities needed for the processing of containers of various sizes:

Containers of varying types should be made feasible with the content chosen. Also, to ensure the standardisation of nursery activities, there should be uniformity between containers of any specific size type.

  • Local root-trainer development:

As root trainers are very new to India, suitable root trainers are not available locally, although some businesses develop root trainers on a smaller scale. The aim was to investigate the feasibility to develop root trainers of different sizes and their production costs.

  • The manufacture of elevated platforms

To hold root trainer stock off the field, a raised platform is required. This is to promote root air pruning as well as to ensure improved hygienic conditions. An effort was made to investigate the feasibility of using locally accessible content to create elevated platforms. Three types of the elevated platforms have been attempted.

They include-

  1. Tabletop with an angular iron stand made of wire mesh
  2. tabletop made of iron wire mesh with bamboo/timber pole stand
  3. Bamboo mesh tabletop with timber/bamboo stand

The mesh table made of steel on-top platform is almost fixed and can be used for a long period of time. The platforms made of wire mesh and bamboo mesh are considered to be used for immediate and brief short-term assemblies. The prices differ according to the components used and the scale of the container to be used. There is also space to try different other platform designs using locally accessible materials.

  • The potting medium

Trials of potting media must be performed in the root trainer by growing seedlings in various potting media. Eucalyptus was used for a trial in various growing mixes that are prepared with locally available materials. In the general experiment on root trainers, the following components were used in various combinations- woodland soil, Coconut pit, dust saw, and paddy pod saw. Apart from this, soil-rite and vermiculite are also added to this mixture.

  • Irrigation system

Irrigation is another significant factor in using a root trainer. In this case, conventional rose irrigation is not appropriate due to the limited capacity of the containers and also the availability of root trainers in greater numbers per unit area. Therefore, the option of using PVC pipes and low-cost sprinkler nozzles to create a low-cost sprinkler irrigation system has been attempted. Under such a scheme, irrigation can be done more effectively and faster with just one person to manage the different tasks in the nursery.

  • Shelter above

It is important to think about a variety of locally designed over-roof shelter styles.  A standard nursery offers a simple bamboo/low-cost timber frame for over-roof shelter with dense coloured/white polythene covers.

  • Basis of root trainer’s usage:

In general, root trainer trials show that it is possible in Kerala to use this technology.

However, it is important to standardise the root trainer form and scale, potting media, fertiliser and irrigation regime, and other cultural traditions as a more exacting technology. The selection of root trainers was focused on the knowledge available.

  • Obtainability and reusability of the root trainers:

Root trainers are made of plastic and are therefore similar in their accessibility to polybags

In this situation, however, there is a choice to reuse and use recycled plastic collected from degraded containers. The existing material is used appropriately, thus minimising the need for raw materials.

  • Cost and simplicity in large-scale development

Root trainers are ideal for machine manufacture and large-scale development is possible only when the type, size, and shape of the containers are uniform.

The possibilities for reuse of the price of the root trainer per seedling are also taken into consideration; these are Strongly Applicable in designing the root trainers.

  • The standardised design of containers of varying sizes

As the raw materials used are collapsible and reusable plastic or paper pulp, root trainers of suitable and uniform sizes, and shapes can be developed. These features are strongly applicable in order to obtain desired and well-organized root trainers

  • Strength, longevity, weight and lightness, and capacity

The containers are less in weight, sturdy and durable as they are made of plastic or polythene-covered paper pulp to make root trainers. The shock to the container root system is minimised because they have rigid/semi-rigid walls or have mechanisms to escape damage

The volume required for root trainers would be therefore much lesser than polybags or any other traditional containers. In comparison, the total weight is reduced when the artificial potting medium is mixed with half or one-third of the soil in root trainers. Plastic root trainers are strong, durable and can be reused for 15 years or more.

Score: Strongly Relevant

  • To regulate moisture in root trainers:

The openings at the bottom of the container allow drainage of water which includes structures such as container shape, which is slightly tapered, suitable container size, and superior potting media. These provide sufficient water-retaining capacity and make it easy to control moisture.

 The sprinkler types used in the irrigation system for root trainer nursery and other control mechanisms like air, light, and temperature also help manage moisture. The limited bottle-size sprinklers help to prevent the depletion of water due to evaporation.

  • Inertness in biology

The biologically inert raw material used is paper pulp coated with plastic or polythene. The potting medium should be sterile as well. Probably the best-suited Plastic torpedo pot method is beneficial to ensure better sanitation, rendering the jar immune to insect pests and pathogens.

  • Inertness of chemicals

Plastic or polythene-covered paper pulp is the material used in producing root trainers, and there is no study available on the leakage of harmful compounds from these products.

Score: Strongly Relevant

  • Temperature and light-regulating devices

Using suitable colour and thickness of containers direct aeration and temperature through the opening at the bottom of the bottle, drainage holes, elevated platform, and special platforms irrigation schedules help balance light and temperature.

  • Amenities for the safe collection and supply of nutrients

The limited volume of the container, the basic structure, and the regular supply of nutrients in necessary amounts promote the availability of nutrients to the plant’s root system. This procedure eliminates waste.

The superior quality potting medium also helps to preserve and supply nutrients efficiently to the roots in the root trainers.

  • Facilities for Safe Root System Growth

To resist root coiling, root trainers have special features, including vertical ribs. They have improved facilities for regulating moisture, air, light, nutrients, and temperature. This tends to mitigate root strangling, root twists, unsuitable root-shoot relations, and lack of growth in the lateral roots.

  • Availability of information about the use of containers

When it comes to local species and planting requirements, the use of root trainers is very recent. So, the root trainer type and scale, potting media, irrigation, and fertiliser regimes need to be standardised.

Scope for enhancement:

This can be solved through research and development activities. It is possible to carry out root trainers’ production, advancements in the usage of potting medium, project device material, and use organic fertiliser available in the local market.

  • Familiarity and ease of using containers

 Since the root trainer technology is more specific and detailed, more care and consideration are needed for its use.

It is also impossible to use root trainers under the existing forest nursery set-up where individuals managing the nurseries are frequently unskilled. However, separate nursery activities can be managed with simple machines and huge stocks can be reserved in small spaces. The entire nursery administration can be managed with less trained workers.

This difficulty can be absolutely solved by a study of efforts for growth and development. A simple method of filling the potting medium in the root trainers is facilitated as the capacity of the jar remains considerably lower, potting the soil into the root trainers is pretty straightforward. Root trainers often do not have the time to open the polybags.

 Score: Strongly Relevant

  • Facilities for fast stock removal

Root trainers establish a nursery stock with a solid root plug which is easy to detach stock when required. There are also root trainers (book/sleeve containers) available that can be unlocked for stock removal and also for periodic inspection.

Score: Strongly Relevant

  • Facilities to ease nursery and plantation processes; Root trainers vs polybags

The small number of containers needed would help minimise the effort involved in Potting, storing, and shipping nurseries. Since the number of containers that can be carried is 5-6 times greater than that of polybags per unit area. The container’s optimum size also allows the utilisation of nutrients and water more effectively since they are entirely inside the stock’s root region.

  • Cost performance

Field trials are needed for detailed cost results. The details available, however, suggests a low total expense. This involves low cost/stock of pots, low cost of potting, drainage, handling of nurseries, shipping, and shorter nursery regime to help mitigate nursery management costs.

Another benefit includes high post-planting survival and improved growth of trees.

How to make your homemade root trainers


  • Cut a sufficient piece of cardboard from a carton box or a package, 8 inches (21cm) long by the depth you want to be deep in your root trainer, then 4 inches deep… 4 inches high.
  • Use a steel ruler one inch high, line it up at the edge of the card, and press down while raising the card to “crease” it.
  • Shift the ruler, line it up with the crease that was just made and repeat it with the second step.
  • Do this all the way to the top, then turn over the card.

Finally, to preserve its form, fold it up and tape it.


  • Take a newspaper and rip up six of each double-page cover.
  • The main folding is folded down and then folded in thirds around each page.
  • Take each paper strip and roll it into a loose cylinder.
  • A bottle can be a strong source of help to tighten the roll (although not too tight, otherwise it cannot be picked up until done), focus on rounding the ends, fold them down a few times (a couple of folds, then reversing the tube on the bottle).
  • Create at least 3-4 small folds at each end, which is enough to keep the tube’s shape and provide some support to the ends.

Stuff them with a potting combination (a mixture of fine compost and perlite) and water them to finish them off.


  • Take a few paper coffee cups
  • Make a 1-inch circular hole in the base
  • Place them inside a tray
  • Fill with soil mixed with compost, & cocopeat
  • This should be fine to start you on homemade root trainers

A study on root trainers

According to a report on root trainers, a ranking of ‘highly suitable’ was obtained for 15 out of 18 criteria for root trainers, so they are most suitable for the present-day requirements. However, they are unsuitable concerning only 2 specifications.

Root trainer technology can only be implemented when the following issues are taken into account:

  • the limitations such as the absence of proper knowledge in the local market and
  • the non-existing familiarities and convenient usage of root trainers.

However, the only alternative accessible at present is the usage of a polythene bag, although they are moderately unacceptable for around 7 specifications.

The findings found from the related assessment of containers also emphasise the crucial findings.

The traditional containers used for planting do not possess any additional features in the comparative studies. This gives us a clear understanding of the drawbacks of outdated potting containers. Hence, choose them only in the absence of root trainers.

But for criteria such as availability of know-how and familiarity and ease of use, root trainers are superior to polybags. However, considering the benefits of root trainers, they could not be used now as they could not meet the minimum requirement for 2 criteria. So, it is appropriate to stick with polybag nurseries for the time being.

root trainer review is a scope for the change in obtaining a healthy root system. The analysis showed that it is important to mitigate the harmful effects of polybag containers in nurseries. The optimum capacity, the adequate quantity of well-spaced drainage holes, the aerated organic potting mixtures with a suitable amount of sand, adequate watering, the appropriate usage of fertiliser and the removal of unnecessary nursery stock facilitate healthy plants.

Considering the utility of root trainers, the research and development focus must be directed to addressing the shortcomings in two requirements, i.e., lack of knowledge in local areas and lack of awareness to use. Ultimate efforts are important to regulate the usage of suitable root trainers.

The structure, media for potting, fertilisers, their rules of utility and other aspects are considered to obtain desired root trainers. Relevant elements like the

  • the overall planting system,
  • planting shelter,
  • low-priced housing.
  • Irrigation scheme for sprinklers,
  • Planting methods.

These are the vital factors to be implemented in nurseries and agriculture on large-scale production.

Purposes involved in locating and planting processes in root trainer’s utility enable a feasible way to unfold the plants. The growth can be observed without damaging the plant.

Evaluation of the root trainer’s properties indicates that they are equivalent to, in certain ways, the polythene container. The number of containers needed is 4 to 6 times smaller than that of polythene bags due to the containers’ rigid design.

This greatly decreases the potting prices and the quantity of the root trainer’s stock. As a result, the cost of management and transport is reduced. Nursery management is more reliable and cost-effective since more bins can be maintained per unit area than polythene bags. The raw material demand is also much lower due to the likelihood of reusing root trainers’ recycling usage.

The use of root trainer pots also effectively aids in the case of the waste management process. Nevertheless, for optimal usage, root trainers need a complete improvement in the existing forest nursery activities.

  • It is important to use an efficient mixture in pots with
  • improved moistness,
  • retaining capability, and
  • drainage functioning better than soil

To ensure optimal growth conditions. It is also important to provide an adequate platform which is raised above the ground to sustain root trainers, plant roof shade, and sprinkler irrigation system.

Since root trainers need more care and skill, field workers need to be properly qualified before the equipment is used on a wide scale.


  • Clone seedlings with root trainers:

The saplings propagated vegetatively and developed from a single superior desirable quality tree along with the octet comprising a clone. Clonal saplings of each clone are unvarying and true to all the genetic qualities of the mother tree. The genetic traits differ from clone to clone, and they signify a peculiar genotype.

Hence root trainer methods have become very popular in nursery production. Root trainer methods are used for the clonal production of saplings, and these days it has become vital. Through this method, clonal saplings are produced on a large scale in a short period of time. This can be achieved in less than 100 days efficiently.

A healthy and well-preserved clonal production of 25-30 days old after pruning is identified and chosen to select and collect clones. These are used in clonal seedlings generation and processing. Numerous advantages of root trainers can be clearly identified, such as

  • Less labour
  • Cost-effective
  • Hassle-free, transferable, and transplantable by the farmer’s community.

The findings presented found that the averages of the five experiments using clonal and conventional approaches to increase the saplings showed that the proportion of sprouted saplings was higher in clonal saplings (93.4 %) relative to the traditional approach (87.0 %)

The survival rate of clonal saplings was also higher (88.2 %), led by the conventional approach of growing saplings (76.4 %). The study showed that clonal saplings’ survival improved by 13.32 % relative to conventional approaches, suggesting their dominance over the traditional practice. Hence root trainers are adopted for their exemplary and outstanding results. They had brought enormous changes in everything from standards to commercial production.

There were hardly half a million saplings produced by conventional (bed) saplings processing. Whereas in the case of the development of clonal saplings by root training procedure, it is possible to produce an average of 2.5 million saplings per year with a market value of Rs. 5/- per sapling. We can find a fivefold increase in production through root training technology.

Based on the above facts, if clonal seedlings obtained by root trainers’ production are introduced, the Seri bodybuilders will obtain an enormous margin of financial benefits.

Maintaining the development of shoots to be used as cuttings close to the root system by repeated pruning or pinching operations has been shown to encourage their ability to establish adventitious rooting and true-to-typing by root training methods.

Root trainers in the wholesale market play an imperative role. They are cost-effective and beneficial for commercial productions leading to huge profits. In the unique moulding method known in forest nurseries, the maker of root trainers/containers for nursery plants has pioneered the production of millions of tree seedlings in the root training growing system for two decades.

  • Growth of Rubber plants using root trainers

The process developed by the Rubber Research Institute of India (RRII) involves growing plants called root trainers in specially built-plastic cupsThus, cultivated plants grow straight and deep taproots and profuse lateral roots. On the inside walls of trainers, vertical ridges allow the roots to expand. Coir pith is used for potting in this technique, unlike polybag species.

Root trainers’ trainers’ bins

To ensure healthy growth and orientation of roots, the form and form of root trainer containers are scientifically engineered and manufactured. The root trainers are made of polypropylene, the shape is tapered from the top downwards of the container which ends up in a drainage hole at the bottom. Some lengthwise ridges that finish at the drainage hole at the bottom of the root trainers possess varying holding capacities ranging from 50 ccs to 1000 cc and are available in the market for the inside wall of the container. Larger containers sufficient to handle the long taproot of budded stumps are necessary for rubber.

Green budded stumps could be planted in root trainers which are 26 cm in length having a holding capacity of 600 ccs, while brown budded stumps need larger containers of 30 cm in length with a holding capacity of 800 ccs.

Medium for potting the root trainers

In the root trainer implantation process, the availability of a good potting medium is essential. Some characteristics such as lightweight, crumbliness, low bulk density, good drainage and absorbency, good water-holding capability, simple bendability, no characteristic fertility, and light acidic are stated to have a good potting medium.

They should be free of fungal spores, insects, weed seeds, etc. Cured coir pith has many features to act as a strong medium for potting and is considered suitable for filling the root trainers. In most of the coastal regions, coir pith is accessible in abundance. The simple accessibility of this sustainable source of the good potting medium as a waste by-product of the coir industry is the most significant factor that encouraged the effective standardisation of the root trainer planting technique for rubber.

Root trainers filling

Coir Pith is a nutrient-free inert substance and must thus be enriched by mixing 250 grams with powdered rock phosphate, neem cake, and bone meal each per carrier of coir pith. Then 5g of a fungicide (Dithane M-45 or Indofil M-45) and a pesticide (Malathion) are also added to the coir pith and thoroughly combined. Tightly filling the container with coir pith is necessary because when the root plug is removed from the container to transplant to the desired region, loose coir pith can split and destroy the root system. For close filling at the bottom 1⁄4 of the container, careful attention is needed as this area is highly prone to breakage.

The central hole is used to remove the excess water and also to facilitate aeration within the bottle. It will be catastrophic to have this dominant opening, shut, as it will lead to significant damage to the roots caused by waterlogging.

The planting of green budded stumps in root trainers is favoured.

Medium-sized brown budded stumps may also be used for the growth of up to one year, given that the stumps are moderate in size. Green budded stumps are normally planted with a holding capacity of 600 ccs in root trainers of 26 cm in length. Brown budded stumps need thicker 30 cm, long root trainers, with a holding capacity of 800 ccs.

The main taproot is pruned proportionate to the jar’s length, and good bud grafts are taken out. The central hole is expanded with a stick of sufficient size in larger roots. The unwanted coir pith is removed from the top of the container and is transferred after planting the budded stump, holding the pruned sides in place.

Irrigation activities

To ensure maximum growth and vigour, an essential cultural activity in the root trainer nursery is judicious irrigation. When budded stumps have been rooted, the root trainers are well watered until the whole potting medium is drenched. Daily irrigation is advised when the first whorl of leaves achieves maturity, and irrigation could subsequently be limited to everyday alternation.

In all conditions, waterlogging should be stopped. Even 2-3 hours after irrigation, if the water is not pumped out, it may be attributable to an obstruction in the drainage hole that must be quickly cleaned, and adequate water drainage assured. Except for the duration of a week, waterlogging may do permanent damage to the root system and can dry up the vine. Irrigation may be skipped for 2-3 days in the event of moderate weather. The soil where the root trainers are piled should also be drenched with water once or twice in a week during the summer season.


The amount of potting medium found in root trainers is significantly smaller than that contained in polybags. It is also very critical that root trainers’ moisture level is always kept at an optimum level. Excess moisture loss occurs directly from the upper surface of the potting medium or indirectly from the plant. This is managed by providing 50 % shade by creating an overhead shade with suitable materials such as a shade net, coir mat, and coconut leaves. To promote air circulation, the sides can be left open. During the commencement of the rainy season, the shade may be entirely lost.


Hardening is a cultural pre-planting procedure in the root trainer technology by which the plants can meet such unforeseen tension circumstances as may arise while transplanting to the field.

The dirt under the root trainers is discarded for hardening, and the roots which are outgrown from the drainage hole in the field are gently clipped with a knife. On plants exceeding two whorls of leaves, this must be achieved as early as possible since more delay can lead to excessive growth of roots in the ground soil.

After plants are moved to the stand for hardening, large roots can delay the recovery process.

For a minimum duration of eight weeks, the root trainer plants are kept in the stand, off the field. If irrigation is conducted regularly and the manuring process is continued with 2% NPKMg solution (10:10:4:1.5), an extra whorl of leaves will appear weekly within 4 to 6 weeks by the time the plants are arranged for hardening. The growth and efficiency of progressive planting material are closely associated with the amount and production of lateral roots, so the most significant benefit of the root trainer planting method is this enforced regeneration of lateral roots.


On transplanting to the area, root trainer plants exhibited 100 % establishment success. Air-pruned roots resume development on the next day after transplantation to the area. This swift and robust root growth is primarily responsible for the complete achievement of the root trainer planting technique.

When transplanting, as in polybag planting, the bud amalgamation should stay above the soil level, facing the North-East direction. During a successful season, field planting needs to be completed. If extreme drought is observed immediately after transplantation, the plant base can be covered with dry leaves, and shade with coconut fronds is suggested.

To overcome the defects of polybag plants, the root trainer planting method has been standardised. In addition to overcoming the risks, the root trainer planting technique was incredibly cost-effective.

The cost of the budded stump is similar to all root trainer techniques of planting. The cost is measured as Rs. 20 per unit for the root trainer and the carrier. For a minimum duration of fifteen years, the root trainers and carriers could be reused, and hence the annual depreciation could be approximately Rs. 2 per unit. This amount is comparable to the cost of a polybag.

The most appealing economic feature of the root trainer planting strategy is the incentives gained during transportation, field delivery, and transplanting to the pit. The root trainers are more affordable compared to the poly bags due to their compact design and ample features. The delivery of root trainer plants in the field is effortless. Root trainer plants could be easily and effortlessly transplanted into the pit. Even an unskilled worker could produce better planting turnover compared to a polybag plantation.

This approachable field planting technique encourages smallholders and marginal plant growers, without relying on professional staff, to conduct their planting operations independently. A calculation concluded at the RRI of India found that the cost of root trainer plants for shipping, delivery, and field planting is around one-third of the cost compared to polybag nursery plantations.

Photo credits:
In infield trials, root trainer plants grew without transplantation failure; in reality, growth was better than polybag plants. In 2005, root trainer and polythene bag methods were used to cultivate clones of the 400 series and the RRII 105 variety in Kanjirappally. Of the 400 series clones, ninety per cent of trees and 50 per cent of RRII 105 have now reached tappable girth.

  • Coir pith is considered as the best for better root establishment mixture among the potting media used for RET.
  • A feasible solution is using waste materials as a container growth medium for the root elongation of rubber.
  • The findings of the two synthetic materials, PVC dust, and Styrofoam, are also promising, prompting more studies. The environmental issues created by the build-up of these synthetic materials, including tire waste, can be addressed to a large degree by their careful use.

Commercial production with huge profits using root trainers

You might need to adapt other nursery procedures to the system’s special specifications if you chose the root trainer system. Choosing a fibrous potting substrate is essential so that it does not spill through the containers’ bottom holes.

Not ideal are sand and soil or mixtures containing a lot of sand or soil. To allow for air pruning, you need to build elevated frames such that the base of the root trainers is at least 30 cm above the ground. You may need to raise the watering routine because the root trainer cells also have a lower volume than polybags.

Management improvements also involve the out-planting phase. If there is a good fibrous root system connecting the plug, the ‘plugs’ from root trainers can be carried into the field like bare-rooted seedlings. It lowers the cost of transport and would need to take the same care as bare-rooted seedlings desiccating the plants:

  • The seedlings must be planted on the same day to extract them from their pots. Never let dry out of the root system. For all stages, the seedlings are kept in the shade. To prevent crippling the root structure, particular caution must be taken.
  • When evaluating the cost economics between the development of clonal by root trainers and conventional (bed) saplings, it was noted that there was a large profit margin between the two methods.

 It is used for the germination of different seedlings. Equipped with high-grade plastic HDPE products that improve their longevity and resistance to chemicals. It is built to grow plants hygienically and stably with some gaps. Without complications, it is simple to reuse again. In nursing, agriculture, horticulture, greenhouse, kitchen garden areas, etc., Plastic Seedling Tray is suitable for bringing long-lasting returns. To obtain the desired clone production by root training, these steps play a vital role:

The 4 Tree Root Teaching Phases

Step 1

The positioning and defence of the root flare is the first step in the training of tree roots. The initial root flare of the trees must be identified. Then, all excess roots should be separated from the trees’ initial root flare at a perpendicular angle. Be cautious not to confuse the root flare with the tree’s bud’s union if the tree has been spread asexually by grafting or budding.

Step 2

In container-grown plants, the second stage of tree root preparation is eliminating the outer region of roots that were on the outer side of the containers and the outer bottom roots. This technique is called “Root Shaving” and with a sharp nursery spade, hand pruning saw, hand pruners, or a battery-powered Sawzall, it can be achieved quickly. In the bottle’s exterior regions, the vast majority of the twisted or tangled tree roots grown in containers are found. The remaining roots in this region that are cut should be at a perpendicular angle from the tree’s trunk.

Step 3

Positioning the trained roots (steps 1 & 2) in the next container or their final planting position is the third step in tree root training. Ensure the root flare is placed on the soil line. The root system’s final visual inspection for any root defects can be removed from the tree’s root system before the soil is covered. Roots that would be bent or angled toward the tree’s centre stem (trunk) would be those defects.

Step 4

Proper mulching is the fourth and final step and a key to long-term management to keep a tree root defect free.

Mulch placed anywhere near an interface of the trunk-soil line of trees will lead to the formation of adventitious roots that can lead to girdling. In certain circumstances, these stem girdling roots are defects that can be cut, and in some cases, these cuts can cause more harm than benefit, but in other cases, they can fuse into the tree trunk, and their removal can cause more harm than good.

Some of the Indian state governments that have implemented root trainers:

  • The Forest Development Corporation of Maharashtra (FDCM)
  • Kerala state government
  • Haryana
  • Karnataka
  • Chhattisgarh

Kruger Root trainers – Torpedo pots

Kruger Industries has helped grow agriculture by efficiently manufacturing supreme root trainers and planters.

The state-of-the-art injection moulding facility has excellent and high-quality processes that always deliver to achieve customer satisfaction. As thermoplastic materials provide affordable, long-lasting, and reusable root trainers. These super standard moulds are obtained, ensuring trust to the clients as Kruger Industries is committed to providing large-scale first-class quality containers. These satisfy the needs of agriculturists, farmers, and nurseries to a great extent. The products ensure that the requirements are met with regard to the advancements in agricultural technology.

Usually, manufacturing with injection moulding requires a substantial initial investment in tooling. That’s why building the mould correctly for the first time is extremely valuable, rather than trying to start anew after discovering significant defects. Defects related to the method or substance of moulding tend to be simpler to solve and less expensive. Kruger is known to manufacture defect-free items on its own. To remove any form of defects in their products, they ensure the injection procedure with keenness. To manufacture high-quality products of standard quality, they correctly evaluate and apply the moulding procedure.

A variety of root trainers are available from Kruger Industries, in block frames or single cells. Kruger agri-products with high-grade plastic material can be customised according to customer requirements. Kruger products are cost-effective and long-lasting and can be reused for many applications to grow fruits, vegetables, flowers, etc., on a commercial basis.
Kruger is recognised for delivering consistency in its moulding services and products, taking into account the end customer’s needs.

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