How to Transplant Houseplants to Your Outdoor Garden


1 Thin the Herd

Gardeners often plant two seeds or more per container. "The extra plant is an insurance policy in case one seed doesn't sprout," Myers says. But if both seeds germinate, there's usually not enough room for both seedlings. As hard as it is, you have to sacrifice the weaker plant so the stronger one can thrive.

Wait until the stems have at least two sets of leaves before deciding which one to keep, Myers says. "Don't do anything until you have two true leaves." Then, clip the weaker one at ground level with scissors.

However, if the seedlings are far enough apart that the roots aren't entangled, you can move one to its own container until it's ready to be planted outdoors. "Use a kitchen fork to carefully lift and separate the plants with minimal impact to the roots," she says.

2 Upgrade to Larger Containers

Plants in small containers can quickly become too big for their space. So if the outdoor growing season is several weeks off where you live, move the plants to larger containers indoors. "If you're growing plants indoors for a month or less, you should be good," Myers says. "But if it's longer than a month, the plants may outgrow the container."

3 Prepare Your Seedlings for the Harsh Outdoors



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4 Prep the Outdoor Soil

Enrich the garden soil with some type of organic matter. "Adding compost or peat moss to the top 12 inches of soil really improves the water retention in sandy soils and the drainage in clay soils, so the plants get the right amount of moisture," Myers says.

Also mix in a slow-release fertilizer, which provides nutrients throughout the season. "It minimizes the work you have to do," she says. Place the organic material and the fertilizer on top of the garden soil, then use a shovel or tiller to turn the soil over and mix everything together.

5 Transplant the Seedlings

"Before you transplant, always make sure the danger of frost is gone," Myers says. She likes to place a floating row cover over the garden soil to warm it up before planting the seedlings.

If you're transplanting a plant in a biodegradable container, you can place it directly into the ground. "Slice through the sides with a knife to open it up. This speeds up the growing process because the roots go into the soil." If the container is not biodegradable, then gently remove the plant from the container. "You want to slide it out of the pot instead of pulling it by the stem. Tip over the container and slide out the plant," Myers says. "Crumple up the sides if the plant won't slide out on its own. As a last resort, cut away the container. That's better than damaging the roots."

If the roots encircle the container, loosen them up. "You need to tease the roots, and that means loosening them from a tightly wound ball," Myers says. "If you don't, they will continue to grow in a circle."

Plant the seedlings at the same depth at which they were planted indoors—except for tomatoes, which can be planted up to 6 inches deeper. If your plants have flowers or blooms, pinch or cut them off, and cut back long, leggy plants before transplanting. "It's hard to cut them back when they're in bloom, but this way the energy goes into the roots, so you get a fuller, healthier plant and eventually many more flowers."

6 Continue Warming the Soil

Myers also likes using her floating row cover after the seedlings are transplanted to help the soil warm up faster. "Warming up the soil and air around the plants will help the plants adapt to the outside," she points out. If you don't want to use a row cover, cut the tops off gallon milk jugs and put the jugs over the plant. "Warm soil and air speeds up the plant growth. You'll be the first one with the big red tomato."

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7 Water Often, Then Back Off

Giving the right amount of water can be tricky. "Water often enough to keep the soil moist," Myers says. In the immediate days after transplanting, water once a day or every other day. Then gradually cut back to two 1/2-inch soakings each week in sandy soils, or once a week in clay soils.

"If you water every day, you encourage the roots to stay near the top of the soil," she says. "Then when we suffer excess heat, drought, or go on vacation, the plant will die because the roots are near the surface where there's no water." Cutting back on your watering encourages roots to dive down deeper.

8 Finish With Mulch

Once the plants are in the ground, cover the surface around the stems with mulch. "It helps contain the moisture, and as it decomposes, it improves the soil," Myers says. Mulch also suppresses weeds and minimizes soil erosion from pounding rainstorms.