When Do I Transplant Cannabis Plants?
Why Should I Transplant My Cannabis Plants?
There are advantages to transplanting your marijuana, and this transplant guide and tutorial will teach you when and how to transplant your pot plants perfectly every time. But why should growers transplant their weed plants in the first place? Why not just plant them in their final container from the beginning? The reason is that a proper transplanting regimen actually makes your plants grow faster in the vegetative stage!
Transplanting Young Cannabis Plants At The Right Time Makes Them Grow Faster!
If you start your cannabis plants in a relatively small container they will grow faster than if you planted your seedlings or clones in a big container. This is because it’s easier for a small cannabis plant roots to get the right mixture of air and water when they’re not waterlogged in a big container.
Small Cannabis Plants Grow Faster in Small Containers
But if you do start small, you need to transfer your plants to bigger containers as they grow to ensure the roots have plenty of room to expand. When roots don’t have enough room, they’ll eventually form a “wall” around the edges of the container. This can cause an array of strange root problems.
If left in a container too long, the cannabis plant will actually become “root-bound.” Think of it as if the roots are choking themselves.The plant roots are unable to effectively get the right ratio of oxygen, water and nutrients, and unless the plant is transplanted, the problem continues to get worse as the roots wrap tighter and tighter. Some growers will even use too-small containers to constrict their cannabis plants on purpose and keep them from getting bigger! So when it comes to transplanting cannabis, you want to make sure you transplant at the right time so your plant roots never run out of room. You’ll actually be hurting their growth if you wait too long to transplant!
A root-bound cannabis plant – transplant your plants before it comes to this!
Root-bound cannabis plants grow very slowly and may even stop growing altogether. In addition to proper transplantation, you can prevent cannabis from getting rootbound by growing plants in smart pots (fabric pots) or air pots since they let air in from the sides. This automatically “prunes” the roots around the edges so they can’t form a wall. Plants don’t get rootbound, and tend to grow faster overall in containers like this compared to regular containers, but they need to watered about twice as often as a similarly sized regular pot since the growing medium is constantly being dried from the sides.
Smart Pots (Fabric Pots) & Air Pots Prevent Cannabis From Becoming Root-Bound
They also make it much harder to overwater your plants. The main drawback is they need to be watered much more often than a regular pot. (learn more about them here)
It is really nice that cannabis plants just plain grow faster in pots like smart pots and air pot. I personally recommend them if you can get a bigger size so you don’t have to water as often. Besides solo cups, fabric pots are the only type of container I use for growing cannabis in soil or coco coir! But I digress…
When a marijuana plant is root-bound, it may display a host of seemingly random symptoms such as drooping and nutrient deficiencies, but usually the main symptom is slow growth.
Root-Bound Cannabis Plant in Solo Cup
Drooping, strange leaf symptoms, yellowing and other cannabis nutrient deficiencies can be caused by a too-small container, like the plant pictured below.
The roots are unable to get the right mixture of air, water and nutrients in a too-small container because the roots are wrapped around the edges. The best (and really only) way to fix up a cannabis plant that has become rootbound is to transplant it to a new, bigger container.
Remember, it is okay to plant your young cannabis in a large container right from the beginning if you want to avoid transplanting your marijuana altogether; just know that they may grow a bit slower for the first few weeks compared to if you started them in something small like a solo cup. If you do want to achieve faster growth rates with transplanting, this tutorial gives you a good general guide to make sure you transplant at just the right time, so your plants never get stressed out, and grow as fast as possible.
There’s nothing wrong with planting seeds directly in a big container! The cannabis just grows a little bit slower at first.
How Can I Tell If My Cannabis Plant Is Rootbound?
It can be hard to know exactly when to transplant your cannabis plants into a new container. Here are some scenarios where you might consider transplanting your plants:
- Soil is drying out too quickly – When your container is drying out only a day or two after each watering it means your plant is drinking fast and needs more water than your current container can hold
- Plant is getting root problems – A cannabis plant can start showing root problems when it’s kept in a too-small container or if it’s become root-bound. These root problems can cause the plant to become droopy, or show unexpected leaf symptoms or deficiencies (such as spots or yellowing leaves). Whenever literally everything else is right but you’re still experiencing these problems, it may be a sign you need to transplant.
- Plant has grown a lot or been in the same container for months. If you’re keeping a mother plant for months, or if a plant has doubled in size in the same container, those are signs you may need to transplant to prevent your plant from getting rootbound.
- Plant is tipping over from its own weight. When your cannabis plant is much wider and taller than its container, it’s easy to tip over and therefore should be transplanted to a bigger pot that can hold it steady.
- Plant is just plain too big for container (pics below) – There are some pictures below to give you an idea of what a plant looks like that needs to be transplanted. Some plants are just plain too big for the containers they are in.
Now let me give you a few real-life examples you can use to refer to. The following transplanting pictures should help give you an idea of exactly when to transplant your cannabis plants!
These marijuana plants are ready to be transplanted
This cannabis seedling is ready to transplant – you can transplant a cannabis plant from a solo cup once its leaves reach the edges. Don’t wait much longer than this for a seedling in a solo cup!
This next cannabis seedling is huge for a solo cup – it should have been transplanted weeks ago! The strange curling symptoms are a sign that the roots aren’t happy. Once this plant was transplanted it started growing perfectly again.
Sometimes a rootbound cannabis plant shows strange symptoms that almost look like nutrient deficiencies and/or overwatering, when the real problem is it just needs a bigger container!
This next marijuana plant is also way too big for its solo cup. Although it still looks relatively healthy, notice the yellowing bottom leaves with spots and bluish color. If this plant isn’t transplanted to a bigger container, those leaf symptoms will continue moving up the plant and start causing problems. Additionally, most likely this plant would already be much bigger if its roots weren’t being constrained by the solo cup.
These marijuana plants aren’t showing symptoms yet, but they’re getting too big for their pots and should be transplanted soon, especially before they start flowering!
These cannabis plants are way too big for their containers and they’re starting to show strange leaf symptoms, drooping and curling because roots aren’t getting what they need
When a cannabis plant is much wider than its pot, it should be moved to a bigger container even if it’s not showing signs of being root-bound. Not only will the plant roots love the extra space, your plant won’t be so easy to tip over!
This cannabis plant was not transplanted before it started flowering. Although it was healthy its whole life, in the middle of the flowering stage it started drooping and showing these symptoms, because the plant was rootbound. Although it’s generally not recommended to transplant a marijuana plant in the flowering stage, that’s what was needed to fix up this plant and get to harvest!
Seed to Final Container: When to Transplant
1.) Start seeds or clones in a seedling plug/cube or germination station and wait until you start seeing roots come out the bottom (or skip this step and plant seeds directly in a solo cup).
This grower has waited too long before transplanting to bigger container
(it’s good to transfer once you start seeing roots)
2.) Place young plants in a solo cup with holes in the bottom to allow water to drain freely.
Make sure to cut holes in the bottom of the solo cup first, so water can drain out the bottom easily!
Just dig a small hole and stick the starter cubes directly into the new growing medium.
Allow them to grow a few sets of leaves, until the leaves reach the edges, like this…
Once the leaves have reached the edges of the solo cup, it’s time to transfer to a bigger container to prevent your seedlings from getting rootbound.
3.) Transfer plants to a 1, 2 or 3 gallon pot
Instead of pulling the whole plant out of the container, it’s often easier to just cut away the solo cup when you plan on transplanting. This is one of the advantages of starting in disposable cups – it makes transplanting easy and stress-free.
4.) Transfer again when plants double in height
Plants are ready to transfer again when they have about doubled in height.
They should look something like this…
If you’re growing big plants and your cannabis plants double in size again, you may need to transfer one more time!
5.) Transfer cannabis plants into their final container! That’s it. You’re done with transplanting your weed plants!
Now you just need to worry about taking care of your plants until you’re ready to start flowering/budding. Remember plants will usually double (or even triple) in size from when you first initiate the flowering stage.
Note: You can skip some of the steps in the cannabis transplant guide above. Just make sure you’re careful not to overwater small plants in too-big containers. Once plants start growing vigorously, you don’t need to worry as much about overwatering.
Tips For Easy & Stress-Free Transplanting
- Water your cannabis plants 1-2 days before transplanting. This will help the growing medium stay together (since it’s moist), but still slide out easily (since it’s not soaking wet).
- Before you get started, fill your new pot with potting mix. Don’t fill the pot to the top, instead leave about 2 extra inches (5 cm). That way you can easily water the plant without all the water running off the sides.
- Water this new container of potting mix before you begin the transplant so it’s nice and moist. If you don’t water the new soil first, it can have a hard time absorbing water after the transplant, and your roots won’t like that!
- Since you will soon be adding a new plant, you want to dig out a hole in the middle that’s about the size of your old container.
- Take your plant, and carefully slide a butter knife inside the container all around the edges to help separate the rootball from the sides of the pot. Avoid grabbing the plant directly by the stem. Try to grab the whole top with a flat hand, and turn the container upside down so you can gently pat the rootball out and catch it with your flat hand. You may have to gently pull the plant out of the container, but go slowly and be gentle!
- Plant the rootball directly into the new container, placing it in the hole you dug out earlier. You may need to add some extra soil to ensure a nice flat topsoil.
- Gently pat down around the roots, to help press everything together slightly, then water your plant immediately. If you do it right, it won’t stress your plants at all!
Minimize Transplant Shock
The process of transplanting can shock your cannabis plants, especially if you wait too long to transplant.
Learn how to avoid cannabis transplant shock!
You can help avoid causing your cannabis plants stress during transplant by following these principles:
- Transplant your cannabis plants after their roots have begun to fill container (to help hold all the growing medium together) but before the roots have started wrapping around the edges (plants have become rootbound).
- Water your cannabis plants 1-2 days before transplanting. This will help the growing medium stay together (since it’s moist), but still slide out easily (since it’s not soaking wet).
- It’s better to transfer too early than too late!
- If the roots haven’t grown all around the sides of the root ball (plant isn’t rootbound), avoid disturbing the roots if possible. There’s no need to shake out dirt, just carefully move entire root ball directly into the next pot.
- Make sure your plants are in their final container at least 1-2 weeks before you switch them over to the flowering stage, and avoid transplanting plants during the flowering/budding stage if you can since the stress may affect your final yields.
- If your cannabis plants seem like they are suffering from transplant shock (leaf symptoms, drooping, slowed growth), it can be helpful to use a seaweed kelp extract (often available as a liquid fertilizer) to help your cannabis recover more quickly.
- If transplanting seems scary, it’s okay to plant your seed or clone in its final destination right at the beginning, just be wary of overwatering until the plant is growing vigorously and has a few sets of leaves. You can increase the amount of oxygen available to your plants by adding extra perlite to loosen the soil and allow water to drain through more easily
- Water your cannabis properly after they’ve been transplanted for the best results!
If you follow all these steps, you may notice that your plant doesn’t show any signs of stress at all!
What Size Should my Final Container Be?
This depends on what size plant you plan to grow, since bigger plants require bigger containers, while smaller plants grow fastest in a relatively small container. For the best results, you need to match the size of your plant with the size of your container.
A general guide is to have up to 2 gallons per 12″ of height. This isn’t perfect, since plants often grow differently, and some plants are short and wide instead of tall, but this is a good rule of thumb.
So if your final (desired) plant size is…
2-3 gallon container
3-5 gallon container
5-7 gallon container
6-10 gallon container
8-10+ gallon container
Go Bigger If You Need to Spend Time Away From Your Cannabis
However, if you plan on being away from your plant for more than a day or two during the grow, it can’t hurt to go up a size or two. The bigger the container, the less often you need to water. So even if you get slightly slower growth in a too-big container, you will definitely be able to spend more time away from your plants without having to water them!
Did you know that transplanting your cannabis at just the right time will actually make your plants to grow faster? Luckily transplanting is easy with a little planning, and only take a few minutes!
How and when to transplant cannabis plants
To start off the growing process, growers typically plant many seeds in small pots because you won’t know if all of them will sprout (or germinate), and you won’t know if all of them will be female (only females produce buds).
It’s hard to plan out your garden space and plant seeds directly into the ground if some seeds don’t make it; and you don’t want to plant a seed in a giant pot and potentially waste a bunch of soil if it won’t make it either.
So for the seeds that do make it, they will need bigger homes after several weeks of growing and will need to be transplanted either into a bigger pot or directly into the ground.
Check out these additional resources on soil and planting:
Why is transplanting important?
Check out Leafly’s Cannabis homegrow for more videos on growing.
The main consideration when transplanting a weed plant into a new home is giving its roots enough space to expand. Roots need to expand and develop in order for a plant to grow and flourish. The container will determine the amount of space available for roots to grow.
When planting into the ground, make sure not to crowd your plants so their roots don’t run into each other. When root systems don’t have enough room to expand they become rootbound, and the roots become a big tangled mess, choking the plant.
The symptoms of a rootbound plant include:
- Flimsy new growth
- Stunted flower production
- Stem discoloration (reddening)
- Nutrient sensitivity
- Nutrient deficiency
A rootbound plant may also appear underwatered. If a plant requires watering more than once a day, it may need to get transplanted.
You want a weed plant to be in its final pot with plenty of room for its roots before it enters the flowering stage.
When is the right time to transplant?
Here are some indicators that your cannabis is ready for a new container:
- Number of leaves: Young plants sowed in small containers are usually ready to be transplanted after they’ve sprouted 4-5 sets of leaves (this may vary from strain to strain).
- Root development: Check the drainage holes at the bottom of the container—a plant should have a healthy and visibly white root system. Any discoloration or darkening may indicate that the plant has become rootbound, and a transplant should take place immediately.
- End of vegetative stage: Many growers opt to transplant to a finishing pot in the final two weeks of vegetative growth before a plant transitions into the flowering phase. At this point, a plant will explode both in size and volume and will require a substantial amount of space for root development.
How much space does cannabis need?
Not only do certain cannabis strains require more space than others, but outdoor growers need to work within their own garden’s parameters. How much room do you have available in your grow space?
When transplanting, give the plant at least double the space of its previous container. This reduces the number of times you must transplant, and minimizes the risk of transplant shock, which may occur when a plant experiences extreme stress from root disturbance.
Medium-sized indoor plants tend to be fine in a 5-gallon container as a finishing pot. For a plant of this size, you can germinate it in a 4-inch or one-gallon pot, and transplant it to a five-gallon pot before flowering.
A plant tends to require 2 gallons of soil for each 6-12 inches of growth it achieves during its vegetative cycle.
On the other hand, large outdoor plants may require much bigger containers to reach their behemoth potential, sometimes up to 10-20-gallon pots.
When in doubt, always opt for slightly more space than needed. A plant tends to require 2 gallons of soil for each 6-12 inches of growth it achieves during its vegetative cycle. Knowing the potential height of the strain you’re planning to grow is a helpful consideration.
Check out info on a strain’s typical height on Leafly strain pages, under “Grow Info.”
How to transplant cannabis
The process of transplanting does not come without risk. Transplant shock can be incredibly detrimental to the growth and development of a plant, even deadly in some cases. However, through proper execution, the process of transplanting should benefit the plant, and lead to stronger root development and a healthier flower production.
Young plants should originally be sowed in a 4-inch pot, a Solo cup, or a one-gallon pot. This starting pot should be adequate for a few weeks before transplanting is needed.
Again, the first transplanting should occur after the seedling has sprouted its 4th or 5th set of leaves.
After checking the root development and confirming that the plant is beginning to fill the basin with healthy roots, it’s time to give the plant a new home.
- Wash your hands and/or wear gloves to prevent contamination of the delicate roots. Keep the surroundings as sanitary as possible.
- Give the plant a light sprinkling of water to help minimize shock; don’t drench it, as the soil will be difficult to work with.
- Fill the receiving pot with soil, allowing for enough space for the new plant; water in the soil here as well before moving the plant.
- Avoid overpacking the grow medium into a container during and after the transplant. This can compromise drainage and may damage root systems.
- Do not disturb or damage the roots when transplanting; the first transplanting poses the greatest risk for shock, and this occurs as a direct result of root damage and agitation.
- Avoid intense light when transplanting. This will help prevent transplant shock as well.
- Always fully water in the plant once it’s in its new home.
You may need to transplant your weed plant a second time to maximize its growing potential. Always monitor plants for symptoms of distress or overcrowded roots.
The finishing container is the final home for a plant until it’s harvested. This will be the largest container for a plant, and you always want to put it into this pot before the flowering stage. Transplant shock can cripple early flower development of a plant.
- Give the plant at least 1-2 weeks after a transplant before initiating flowering.
- Have plenty of space available in the final container for a plant to fully develop. For indoors, this generally means 3-5 gallons depending on strain selection. For outdoors, generally 5+ gallon containers are recommended (again, depending on the strain).
- Larger plants may require stakes and other supports to avoid structural damage during and after transplants.
This post was originally published on March 15, 2018. It was most recently updated on June 29, 2020.
Learn how and when to transplant, to keep your cannabis plant healthy and vibrant, as well as how to avoid transplant shock.