A lot of people use hydroponic machines to start seedlings. Some people will start seedlings to transplant outdoors, and others will start seedings to transplant to larger containers. This post proves that I’m no exception: I just transplanted my San Marzano seedlings into their final Kratky hydroponic home.
Each method of transplanting has its own risks, as discussed below. By far the biggest risk of all is killing your innocent-baby plant. But if you follow the tips listed below, you will minimise the risk of being a plant slaughterer.
Also know that not all plants should be transplanted as some plants can’t handle root disturbance well, like spinach. You should only ever transplant healthy plants.
From Hydroponics to Soil
This is one of the most common methods to grow your plants; starting your delicate seedlings indoors and then planting in your garden when they are old enough to fend for themselves.
You should only transplant once roots have emerged from the bottom of the grow medium. If you wait too long then you risk stressing your plants.
Use grow medium that can be planted outdoors; trying to remove the plant from grow medium can be quite damaging to the roots. I tried separating my lettuce seedlings from the grow medium, and they definitely experienced shock.
Help your plants grow new roots, fast, by using root growth hormones. Whilst I haven’t used hormones on my own plants I have read online people recommending SUPERthrive Plant Vitamin Solution and HydroDynamics Clonex Rooting Gel.
Keep your soil well watered for a few days. You want the soil slightly damp, but not holding so much water that root or mould will grow. If your soil is well draining then consider watering a couple times a day.
You can also add a diluted nutrient solution to your water to help the plant get any extra energy it might need to grow new leaves and roots. This can be the same nutrients that your seedlings were growing in. Don’t give them full strength nutrients yet, as too much can actually harm your plants.
From Soil to Hydroponics
It is possible to transplant from soil to hydroponics, though many hydroponic growers like to keep their grow areas sterilised. Introducing dirt grown plants into a grow room can also bring the risk of unwanted bugs and diseases, potentially harming other plants (or even loosing all your crops!). I have personally lost entire crops from an exposure of an aphid infected plant, and so now I will only grow new plants from seeds.
Let your plant’s soil dry out prior to transplanting; dry soil is much easier to clean any dirt from the roots than wet. Once you have removed as much dirt as possible, then submerged the roots into a bucket of water and rinse any remaining residue. The roots need to be as clean as possible; dirt will contain bugs, algae, and can even damage some hydroponic pump systems.
Place your plant into a net pot and gently pull any long roots through the net pot holes. If the roots are fragile and just break, it’s better to keep them inside the net pot than risk damaging them. cover thoroughly with grow medium like clay pebbles. You need to ensure that no light can enter into your water reservoir.
Depending upon your hydroponic setup, make sure that air is still getting to the roots. Many people will use an air-stone to oxygenate your plant roots. If you are doing the kratky method then you should only submerge the lower roots and net pot, keeping at least half above the waterline to avoid drowning the plant.
Finally, your plant is going to go into shock, potentially a lot. It may look like you’ve killed the plant, with lots of leaves falling off or browning. Give it time and in most cases the plant will recover, anywhere from two days to a couple weeks. You may lose the original leaves as the plant will often abandon preserving those to focus on more important root growth.
From Hydroponics to Hydroponics
This will often be the easiest way to transplant seedlings, if you have planned out your plant growth before hand. The time to transplant is when the roots begin to emerge. Hydroponic roots are very fragile, so if they extend beyond the net cup then they are almost guaranteed to break.
If you know that your plant will need transplanting, try starting the seedlings in the final grow media such as rock wool. Simply transplant the entire cup or simply lift out the plant from one cup and transfer contents to a larger cup, adding more clay pebbles to block out any light.
Don’t make my mistake and wait too long: I transplanted some lettuce from peat moss (started in my Aerogarden) to cloning collars. The process or removing the lettuce seedlings from the Aerogarden net cups and washing out the peat moss caused them to mostly lose their fine roots. They looked dead for the first few days. It took them nearly a week to recover and start showing new growth.
Have you transplanted plants before? Share some of your tips in the comments below.