Mr. Stinky's Green Garden: Tips for Transplanting Marijuana Plants

When it’s time to transplant into larger containers, your choice of container size, container setup, and your transplant method are all important factors. Each can impact the success of your transplant. Since I have have quite a bit of experience with this, I thought I’d share a few tips to help you successfully transplant your young marijuana plants. Some of these tips are common sense while others may be new even for experienced growers.

1. Pot size selection

A great rule of thumb is to choose a new pot that is at least double the size of the old one. Avoid potting up into a huge pot, If you place a 6-pack sized root ball into a 5 gallon pot you’ll have to keep 5 gallons of soil moist which at first the roots won’t reach. This is a waste of water and plant food. Larger pots will also require greater spacing which for indoor growing means more lights and wasted electricity.

2. Assess root ball condition

If your plant has become overly root bound in its old pot, consider breaking up the root ball a little. Gently pull it apart just enough to break the shape of the old pot. Some roots will be damaged but in the long run it will help the roots break out of the old pot shape and aid in root expansion.

3. Avoid Stress

Be sure not to transplant in direct sunlight. Roots don’t like direct light or exposure to dry conditions. Transplant in the early morning or better yet the evening. If possible, allow freshly transplanted plants to remain in their old environment for a day or two before moving them into new conditions.
4. Stake plants
If the plants are tall and delicate, or have a hard time standing on their own, stake them with bamboo and secure with at least 2 plant ties. This helps prevent them from being overturned if jostled. As the plant develops, be sure to remove these ties or they will become tight and even girdle the plant.

5. Rapid potting trick

If you have a lot of plants to transplant consider pre-filling the new containers with fresh planting mix. Use an empty pot, that is the same size as your old pots as a spacer to create a perfectly sized socket for the root ball to fit into. Simply stage the filled, new pots off to one side and remove the ‘spacer’ just prior to the actual transplanting action. This trick can save a lot of time and minimizes air and light exposure which reduces plant stress (see tip 3). Pots can even be filled and staged days before the actual transplant.

6. Do not overly pack the soil

The first time you water the plants the soil settles and natural compacts. this is the ideal amount of compaction for most soils. If you under pack the pots, they might settle to be only half full. If pots are over compacted, the new roots will have to work harder to branch out. Compacting the soil just right takes a little practice and varies with soil moisture content and texture.

7. Always water immediately following transplant

The first watering helps settle the soil around the root ball and collapses any voids that may have formed inside the container, it also helps the young plant cope with transplant stress. Use a watering wand with a gentle diffuser to avoid upsetting the soil and root ball.

8. Post-transplant shock reduction

The only thing plants need after transplant is water. That being said, there are many products that claim to reduce transplant shock. To list a few; Superthrive, Liquinox b1, and Dyna Gro KLN. They all contain a plant growth regulator (PGR) called naphthylacetic acid (NAA). This PGR is also found in many cloning solutions. NAA is very powerful and actually forces the plant to abandon vegetative growth and focus only on root development. If any of these items are used, be sure to follow the labels instructions. Don’t use too much.

9. Post transplant Fertilizer

I don’t recommend use of liquid fertilizer for the first 2 watering. Fresh soil typically contains everything the plant needs for at least 3 weeks. There are of course exceptions to this. Some lower end soils may be nutritionally void, while other mixes are intentionally made this way, i.e. Promix HP, Sunshine #2, and other Peat/perlite blends. These mixes can be amended with dry organic additives, or supplemented with ¼-½ strength liquid fertilizer. Other growers recommend ¼-½ strength bloom food at this time because the additional phosphorus and potassium can aid in root development.

10. Listen to Music

This might seem like an odd one but transplanting can be both stressful and monotonous. Some good tunes will get you in a rhythm, help you relax and make the time go by a lot quicker.