The threat of frost is past, which means it’s time for planting out tomatoes, peppers, and all manner of warm-weather crops here in Virginia. While planting out is certainly not rocket science, and plants can recover from much rough treatment, there are some ways to ease the transition for them, keeping them happier and healthier and ultimately leading to earlier, more abundant harvests.
For a plant, which is built to stay rooted in one spot, every move is a bit traumatic. Compare the two tomato plants in the picture. They were both sown at the same time, from the same batch of seeds, in the same pot. But a couple of weeks ago, I pricked one of them out of the original pot and put it in a new one by itself. I tried to save as much of the soil around the roots as possible, and the plant is now thriving in its new home, but you can clearly see that the move set its growth back significantly compared to the plant that was left in place. This is the kind of setback you want to minimize when you transplant your seedlings into the garden. And here are some tips for doing so.
1. At least a week before transplanting day, begin to harden off your seedlings. Hardening off means getting them used to the outdoors, a little at a time. Plants that have been raised indoors are not used to the bright sunlight, the wind, or the cooler temperatures of outdoors. They can, quite literally, get sunburnt or frostbitten. And it takes several days of exposure to breezes for the plants to develop strong, wind-resistant stems. Start by giving them one hour outdoors in a partly shady, somewhat sheltered spot. The next day, leave them out for two hours and expose them to a little more direct sun. Each day, increase their time outdoors by an hour or so, until they are able to remain outside all day without showing any signs of wilting. (NOTE: Even if you are buying your seedlings from a nursery, they may need some acclimatization, depending on the conditions they were exposed to while being held for sale and how similar these are to the conditions of your garden.)
2. Make sure your seedlings will have plenty of nutrients readily available in their new home. Dig a planting hole at least twice as wide and just a little deeper than the soil in the pot. (For tomatoes, make the hole significantly deeper. They have the ability to grow roots on any part of their stem exposed to soil, so planting them deeper will actually allow them to develop a more extensive root system in a short period of time.) Into the bottom of the hole, sprinkle a little dry fertilizer (a couple tablespoons to a quarter cup, depending on the size of the hole). I use an organic fertilizer that I mix myself. Click here for the recipe. Use a trowel to mix the fertilizer into the soil at the bottom of the hole.
3. Carefully remove your seedling from its pot, doing your best not to damage any leaves, stems, or roots, and keeping as much of the soil with the plant as possible. The easiest way to do this is to turn the pot upside down, supporting the surface of the soil with one hand (the plant stem extending between your fingers), and with the other hand gently squeezing the pot until you feel the root ball inside come free. Then gently slip the pot off.
4. Place the seedling in its new home. But don’t fill in around it with soil yet! Instead, fill the remaining portion of the hole with water*. Do this slowly enough that you don’t disintegrate the soil around the seedling’s roots, but quickly enough that the water accumulates in the hole. When the hole is full of water, gently push soil back into this water, creating a soupy mixture that will help your plant quickly adjust to its new home. The last several trowelfuls of soil will sit on top of this soupy mass and stay dry. This is important. The dry top layer acts as a mulch, preventing moisture from being wicked up out of the ground into the atmosphere. Don’t get this layer wet until you have to. (*: I mix a little Miracle Gro into the water while it’s still in my watering can, to give the seedlings some immediately available nutrients. This is the only non-organic element of my gardening process, and I only use a non-organic product because it’s so hard to find a good organic liquid fertilizer.)
5. That’s it! Now just keep your plants watered and weeded, and you should have some delicious veggies before you know it!
Much of my transplanting technique I learned from Steve Solomon’s excellent book Gardening When It Counts. I highly recommend this book for both beginning and experienced vegetable gardeners.