Seed Starting 101: Planting Out – Tips for Transplanting Seedlings into Your Garden
Harden off your seedlings by exposing them gradually to outside conditions. Don't skip over this step! Tender indoor seedlings planted directly out into the garden can get shocked enough to keel over and die. This also applies to seedlings and plants bought at a garden center, if they've been sheltered. See last week's article, "Seed Starting 101: Hardening Off" for more information.
Think about irrigation. It's much easier to lay soaker hoses across your garden bed now, with no plants to worry about. A soaker hose will water plants for a foot or two out from each side. You can put together a whole system of drip irrigation and soaker hoses and connect it to a set of programmable, electronically controlled valves. Or you can simply lay the soaker hose along your garden bed and connect your garden hose to one end as needed. Quick-connect valves on the ends of your soaker hoses and on your garden hose make watering a snap.
Watch the weather. An overcast day is perfect for planting out, because seedlings will have a chance to adjust to their new spot before dealing with the bright sun. Similarly, I like to plant out in the evening if I know the night will be warm. The seedlings can recover from transplanting during the night and be ready for their first full sun day in the garden.
Plant deeply! With tomato transplants, burying part of the stem when you plant them into the garden will get them off to a great start. New roots will grow all along the buried part of the stem. If I have a tall tomato seedling, I don't dig a 12 inch deep hole. That's too much work, and the soil that far down will still be colder than the roots would like. Instead, I dig a sloping trench and place the tomato seedling sideways at an angle, with the rootball at the lowest point. At least one set of leaves and a bit of stem should stick up above the soil surface. Any plant that can be propagated from cuttings seems likely to grow more roots by burying part of its stem at planting time.
But not too deeply. Some plants, like peppers, don't seem to be harmed by planting them a little lower than they were growing in their pot, whether or not more roots grow. Plants that have a definite crown, however, should be planted with the crown at or above the level of the soil. A "crown" is low central stem with a bunch of leaves radiating out from it. Salvias and strawberry plants, for example, have definite crowns. Don't bury the crown, or the plant may die.
Be nice to the roots. With plastic pots, you can generally push up the bottom of the pot or squeeze the sides a little to release the rootball. Be gentle with the stem, and try not to yank on it. If the plant looks rootbound, with roots circling around the rootball, just tickle the roots with your fingers a little to loosen them up. You may need to break out the sides of the rootball just a little, too, so the roots "know" they're no longer confined to the shape of the pot.
If your seedlings are in peat pots, bury the rim of the pot completely. Otherwise, water will wick away from the roots and evaporate into the air. Also, you may wish to tear away some of the pot. Many plants seem to have a hard time pushing their roots through peat pots. I'm trying a new product this year, CowPotsTM, which are said to break down more quickly so that this isn't a problem.
Time release fertilizers (such as DynamiteTM or OsmocoteTM) and polymer moisture crystals can be added as you're planting. I mix a big pinch of each into the planting hole, following label directions.
Water in the plants after transplanting. This will settle the soil around the roots. Watering with compost tea or a little water-soluble fertilizer gives new transplants a nice pick-me-up.
Plan ahead. Those little transplants will grow faster than you think! Now is a good time to put in stakes next to tomato plants, cages over pepper plants, and trellises for cucumbers and other vines. If you didn't add soaker hoses or drip irrigation to your garden earlier, reconsider. Watering your garden will take up less water and less of your time with a simple irrigation system in place.
You may have started your seeds indoors under lights, or winter sowed, or bought seedlings at a local garden center. But any way you look at it, your seedlings are an investment in a beautiful, bountiful garden this summer. When you plant them out, you want to give them every advantage. With the above tips, they'll get a good start, and you'll be well on your way to a wonderful garden!
See my other articles on Seed Starting, Winter Sowing, and Preventing Damping-off for more information on growing from seed. Also, take a look at Paul Rodman's article, "Watering Wisely" for more information on irrigation systems.
Photos by Jill M. Nicolaus.
Discussion about this article: