The Importance of Transplanting Cannabis Plants
Transplanting cannabis plants to appropriately sized container as they grow is key to cultivating a robust root system and ensuring vigorous early growth. In this article we will cover the why and how to pot up as your plants grow. It is our hope that this article will help you develop and implement an effective transplant strategy for cannabis irrespective of the growing method and media used. I will explain the benefits of transplanting cannabis plants and the underlying horticultural reasons behind this practice. Additionally, I will outline various aspects of a well-developed transplant strategy, including how to prevent transplant shock, selecting suitable containers for transplanting, determining the ideal timing for transplantation, and, of course, the proper technique for transplanting cannabis plants.
The Advantages of Transplanting Cannabis
Getting oxygen to the root system of young plants holds immense importance. Plants thrive when grown in appropriately sized containers, as this facilitates greater oxygen delivery to the root system compared to planting them directly in the final container. Before we became aware of the impact pot size had on the growth of young plants, we used to put clones directly in the final container.
However, we noticed that if we saturated the grow media with water this would cause the plants to grow slower than if we just watered a small area around the main stake and gradually water greater and greater area as the plants grew. It was obvious to us that it was because when you saturate the media in a large pot it was limiting the amount of oxygen that would get to the root zone. It did not dawn on us until later that by keeping young plants in smaller containers, accomplished the same thing only to a greater extent.
Benefits of Transplanting Cannabis Plants in Soil
Transplanting is particularly critical when cultivating plants in soil due to several reasons. Just like in any growing medium, starting plants in smaller containers promotes faster growth and results in better root ball mass and root density. However, in soil, there is an additional crucial reason for starting small and gradually potting up—the air-to-water ratio.
Enhancing the Air-to-Water Ratio
Keeping young plants in smaller containers helps prevent waterlogging, which is especially problematic in soil as it retains excessive moisture. After watering, the soil retains too much water, depriving the roots of oxygen. When plants are larger, the roots can absorb water and prevent waterlogging. However, small plants in large containers cannot absorb sufficient water through their roots, leading to saturated soil. This impedes root growth, increases the risk of “damping off” disease, and can ultimately cause plant death.
Novice growers often believe that starting plants in large soil containers is the easiest approach. However, effectively watering small plants in large soil containers without over or under-watering requires expertise. The truth is that learning how to transplant is easier than effectively managing small plants in large soil containers.
Benefits of Transplanting Cannabis Plants in Coco Coir
Coco coir mixed with perlite is an excellent growing medium because it maintains adequate oxygen levels.
Even after watering, the roots maintain a non-waterlogged state and retain access to oxygen. However, maintaining the proper air-to-water ratio becomes even more advantageous when plants are in appropriately sized containers. Additionally, there are other benefits to transplanting cannabis plants grown in coco, similar to most potted plants in various growing media. Transplanting promotes optimal root structure and root ball mass.
Transplanting Enhances Root Development
In container gardening, roots tend to concentrate at the bottom of the container. By implementing a gradual potting-up process through transplanting, roots are encouraged to colonize the entire volume of the growing medium.
Consider potting-up as a form of root training. At each stage, the plant establishes a new zone of root density before moving to a larger container. This results in a final container where roots densely occupy the entire volume of the growing medium instead of being primarily concentrated at the bottom.
Using small containers during early growth stimulates root ball formation and leads to denser root distribution throughout the plant’s life. Conversely, if a small plant grows in a large container, its roots will primarily occupy the bottom section, leaving a significant amount of unused medium. This prolongs the drying time of the medium and limits oxygen availability to the roots. Furthermore, roots will not colonize the middle of the pot once they have grown past that point. Starting plants in large containers effectively reduces the potential root area and, consequently, the potential harvest.
Slow Growth of Seedlings in Large Containers
Starting plants in large containers not only restricts their potential growth but also slows down their development. Large containers often lack adequate oxygen for root growth in the center of the medium, causing roots to grow primarily at the edges and bottom. This forces seedlings to invest additional energy in root growth at the expense of above-ground growth. Since above-ground growth is the source of all energy, this compound effect slows down vegetative growth during the early stages of the plant’s life.
Initiating seedlings and clones in small containers and gradually potting up promotes more balanced and faster growth. Roots quickly reach the bottom of the container and colonize it, allowing the young seedling to focus on above-ground growth. The potting-up process, transitioning to a second container and eventually to the final container, sustains this pattern of balanced growth and root colonization.
Addressing Transplant Shock
Many growers are hesitant to transplant due to concerns about “transplant shock.” However, when potting up, even novice growers can avoid transplant shock entirely. In fact, the phenomenon of transplant shock, as experienced in horticulture, is not related to the potting-up technique we practice. Potting up involves moving a plant to a larger container using the same growing medium. By taking basic precautions with the roots and the medium, the plant does not experience any transplant shock.
Avoiding Transplant Shock during Potting Up
Transplant shock typically occurs when there is significant physical damage to the roots during the transplant process, particularly when plants are dug up from the ground and replanted elsewhere. This style of transplanting often leads to considerable damage to the tap root. However, in indoor cannabis cultivation, we do not engage in that style of transplanting.
New cannabis growers often worry about damaging roots during transplanting. However, the root damage that occurs during potting up is usually minor and peripheral. Such minor damage to peripheral roots does not cause transplant shock. In fact, slight root pruning encourages the growth of fibrous roots. By following the proper procedure and timing, as explained below, potting up can be performed safely without any fear of transplant shock resulting from root damage.
Simple Steps to Prevent Root Shock
Another cause of transplant shock is “root shock,” which occurs when plants encounter different fertilizers or an unfamiliar growing medium during transplantation. Root shock commonly affects garden starters that are initially grown in seedling pots and then transplanted into garden beds. It can also affect cannabis plants if the new growing medium is not properly prepared.
By taking simple precautions, growers can completely avoid root shock during potting up. Since we are not changing the growing medium but only increasing its volume, it is crucial to ensure that the new medium has the same parameters as the current one. In coco coir or soil, this can be achieved by pre-watering the new medium with the same nutrient solution used for the plants. Measure the Electrical Conductivity (EC) of the water that flows through the new medium (run-off) and verify that it is appropriate before transplanting.
Root shock can also occur if the roots are exposed to light andair for extended periods during the transplant process. Therefore, it is important to prepare the new container in advance and complete the transplant quickly. When the transplant is done swiftly and the new medium contains the same fertilizers and EC, the roots will not experience shock. Instead of encountering transplant shock, you can expect to see a surge in growth immediately after potting up.
Transplant Strategy for Cannabis
The number of stages in your transplanting strategy is determined to an extent by the desired plant size which equates to the amount of time the plants spend in the vegetive stage before initializing the flowering stage. We veg for approximately three weeks, and we have determined that for optimal results a three-stage transplanting strategy works best for our cannabis plants.
The initial stage involves using small seedling pots to allow the young plants to quickly develop a root ball mass. In the case of using clones, it is the actual cloning process that is stage one. In the second stage, the roots have room to expand as the plants grow, but the container size remains relatively small. Once the roots have colonized the second container, the plants are ready to be potted up into their final containers. At this point, the plants will have a substantial root ball mass, providing a solid foundation for healthy and vigorous growth during the remaining vegetative and flowering stages.
Container Selection: Plastic or Fabric Pots
I prefer using fabric pots or air-pots for plants at every stage. These containers offer excellent drainage and aeration, maintaining an optimal air-to-water ratio that promotes healthy root growth. While some growers worry about the difficulty of transplanting from fabric pots, in practice, it can be just as easy, if not easier, than transplanting from plastic pots. I will provide a step-by-step guide to transplanting below.
Pot Sizes for Coco Grows
Coco Stage 1: Ventilated Solo Cups – 1-Pint Coco or the cloning media in the case of growing from clone. Stage 2: Half to One-Gallon Coco Stage 3: Final Containers – Three Gallon Coco if you are in veg for a longer period of time, I recommend potting up to five to seven-gallon pots.
Coco coir provides an ideal growing environment for roots with minimal resistance. As a result, roots grow rapidly during the early stages. To encourage denser root growth, it is beneficial to go through at least three transplant stages instead of directly moving from a seedling pot or clone to a final container. The second stage container should be relatively small to prevent excessive root growth and promote better root density.
The ideal final container size in coco coir depends on your watering frequency. For high-frequency feeding with an automatic watering system, three-gallon final containers are recommended. For hand-watering, five or seven-gallon final containers are better suited.
Pot Sizes for Soil Grows
Soil Stage 1: Ventilated Solo Cups – 1-Pint Soil Stage 2: Two to Three-Gallon Soil Stage 3: Final Containers – Five to Ten-Gallon
When growing plants in soil, it is best to start with the same small seedling containers used in coco coir cultivation. However, since soil provides less space for root growth, larger container sizes are beneficial as the plants mature. The second stage of a soil transplant strategy should involve two to three-gallon containers. This provides sufficient space for root expansion without leading to over-watering issues.
Container size determines the final plant size when using soil as the growing medium. Therefore, the ideal size for the final containers depends on the size of the plants. Most indoor soil growers find success with five, seven, or ten-gallon final containers.
The Best Pots for Transplanting Cannabis
Seedling Pots
Ventilated Solo Cups
Ventilated Solo Cups are the good choice for a starting pot, properly ventilated they create an ideal environment for early root development and offer convenience during transplanting. When it’s time to transplant, simply cut open the cup and slide the root ball and media into the fabric pot.
Second Containers
1-Gallon Transplanter Pots
The transplanter pots feature a convenient Velcro seam along the edge, enabling effortless removal of the pot during transplanting. This set includes five 1-Gallon transplanter pots, and they are also offered in a 2-Gallon size.
Final Containers
When selecting the final containers for your plants, it’s important to take into account the type of growing media you’re using. In coco grows, proper drainage is a key consideration. Smaller containers offer better drainage but require more frequent watering. For most coco grows, we recommend using 3 or 5-gallon final containers as they provide an optimal balance.
In soil grows, the availability of root space is more limited, necessitating larger pots for larger plants. For soil, we suggest using 5-10-gallon final containers to accommodate the plant’s size and root development.
Regardless of the chosen media, we highly recommend using either Air-pots or fabric pots. These containers excel at promoting good drainage and creating an ideal environment for root growth, whether you’re using coco or soil.
#3 Air-pot
We are still testing growing with these pots using coco with an automatic watering system. Early testing has shown great potential, and we will provide our findings in a future article.
#5 Air-Pot
Air-pots are a bit more expensive than fabric pots, but we are hoping they are worth it. If you want to grow giant plants, these #5 air-pots may be what you want.
Although Air-Pots may be slightly pricier compared to fabric pots, I genuinely believe they are worth the investment. The benefits they offer in terms of root health and overall plant growth are outstanding.
3-Gallon Fabric Pot
Three-gallon fabric pots are a great option to use with coco. However, due to the breathable nature of these pots you will need to feed your plants often to keep the media from drying out.
These containers are suitable for both coco and soil grows. When using coco, it is advisable to fertigate your plants between 2 and 5 times per day, while for soil grows, daily fertigation is recommended. Currently, I personally use these containers with coco, and they have been instrumental in my positive experience with Air-Pots. The root development in these pots is truly remarkable and indicative of healthy plants.
5-Gallon Fabric Pot
If you don’t want to feed that often or you want to grow very large plants in coco, you can use these 5-gallon pots.
7-Gallon Fabric Pot
These are the most versatile and least expensive final containers for soil grows. They are also suitable for coco growers who are hand-watering and limited to once daily fertigation.
When to transplant Cannabis: Potting-up
Timing is crucial when it comes to transplanting cannabis plants into larger containers. It’s best to transplant them when the roots have established a solid root mass in their current containers. Transplanting too early or too late can hinder growth and diminish the benefits of the transplant strategy. To determine the optimal time for transplanting, you can observe the above-ground growth of the plants.
Stage 1: Solo Cups Until the Plant has Three Nodes
For seedlings, I recommend starting them in germination media like Jiffy Pellets. Once the root emerges from the pellet, you can transfer the seedling to a one-pint container with soil or coco. Typically, healthy plants will fully colonize the one-pint container by the time they have three true nodes, which usually takes about a week in coco and a bit longer in soil. While the roots may emerge from the container earlier, it’s important to wait until the plant has three nodes before potting-up to the second container.
Stage 2: Second Containers Until the Plant Doubles in Size
The second stage of the transplant strategy focuses on nurturing the growing roots and promoting optimal root mass. Although pot sizes may vary for soil and coco grows, the general rule of thumb for transplanting timing remains the same. Plants should at least double in size in their second container before moving on to the next potting-up stage. If a plant has three nodes when it enters the second container, it should ideally have six or seven nodes before being transplanted again. Depending on the plant’s growth rate, this doubling in size may take less than a week, which signifies the success of the second stage.
Step-by-Step Guide to Transplanting Cannabis
The process of transplanting cannabis is straightforward and can be easily mastered. While different media and containers require specific handling methods, the basic principles remain consistent. Here is a step-by-step guide to help you navigate the transplanting process:
Step 1: Prepare the new container and media
- Fill the new container with the appropriate media, leaving some space for the transplant.
- Thoroughly saturate the new media, ensuring it matches the current nutrient solution, electrical conductivity (EC), and pH levels.
- If necessary, collect excess runoff and measure its EC to ensure it falls within the desired range.
- Create a hole in the new media, larger than the size of the current container, to accommodate the transplant.
Step 2: Prepare the plant
- In soil grows, allow the plant to dry out slightly before transplanting to minimize root damage and ease the transition. However, for coco grows, the plant should remain wet, as it helps the coco stick together during the transplant process.
Step 3: Remove the old container
- Carefully separate the old container from the plant and medium, using a butter knife or similar tool to slide around the inside edge of the pot.
- If using fabric pots, cutting through peripheral roots while removing the pot is not an issue.
- In the case of fabric pots, it’s easiest to use scissors and cut the bottom of the pot, followed by a slit up the side, and then peel the pot away. Alternatively, you can use “Velcro transplanter” pots or modify a standard fabric pot by cutting a side slit and securing it with safety pins.
Step 4: Transfer to the new container
- Quickly place the pot-less plant and media into the prepared hole in the new container.
- Fill in the hole by pushing the media down from the sides.
Step 5: Post-transplant
- Monitor the plant closely after the transplant to ensure it is growing well before resuming any plant training.
- Most plants will rebound and thrive in their new containers, allowing you to resume training and topping 24 hours after the transplant.
- If a plant seems stressed by the transplant, give it some time to recover before subjecting it to additional stress or training.
By following these steps, you can successfully transplant cannabis plants and promote their healthy growth and development.
Set-up Your Grow
Growing Cannabis
- Cannabis Seeds
- Fertilizers & Supplements
- Propagation Supplies
- Plant Training & Care
- Harvest & Processing
Want to Receive our weekly Newsletter full of Grow Tips, News and Exclusive Content? Subscribe Below!
About Our Product Recommendations
Here at 420 Grow Help, our primary goal is to assist growers in achieving the utmost success with their cannabis crops by providing accurate scientific information and sharing proven cultivation techniques. The products we recommend are the very ones we have personally chosen to purchase and use ourselves. We maintain a strict policy of not accepting sponsorships or advertising, and we only endorse products that meet our own high standards. For detailed product recommendations, please refer to our Product and Equipment Guide.
Please note that when you make a purchase through the links we provide, we may receive a referral fee. This is the primary source of revenue that supports and sustains 420 Grow Help. By clicking through our links and making purchases, you are directly contributing to our ongoing work. As an Amazon Associate, we earn from qualifying purchases.
Disclaimer:
The information presented on 420GrowHelp.com should not be regarded as financial, legal, or medical advice. It is your responsibility to familiarize yourself with and abide by the local laws and regulations pertaining to the cultivation, possession, and use of cannabis. Decisions regarding cannabis cultivation should be made in consultation with a lawyer or qualified legal advisor, while decisions regarding cannabis use should be made in consultation with a doctor or medical professional.
