Looking Forward to Moving Seedlings Outdoors? Count Backwards

— Written By and last updated by Diane Lynch

Q: How do I start vegetable seeds indoors?

A: Just because it is cold outside does not mean that you can not start working on your vegetable garden. Many germinate vegetable seeds indoors so that when it is time to seed vegetables outdoors they already have a head start on their garden. Starting vegetable seeds indoors does not require special equipment or plenty of space. Starting vegetable seeds indoors can not only be enjoyable but can allow you to try hard-to-find and unusual varieties.

The proper time for sowing seeds indoors depends upon when plants may normally be planted outdoors. In the vegetable garden, you often have three phases of planting times. The cool-season crops, like broccoli, cabbage, and onion, are planted outdoors in February. Vegetables like tomatoes, squash, and cucumbers are planted outdoors around mid-April. Eggplant, okra, and peppers are planted outdoors around the first of May. The time you plant vegetables outdoors will determine when you start those vegetables indoors because you want to time it so that when started indoors, the vegetables are ready to plant outdoors at the appropriate times. To determine when to start seeding vegetables indoors, count back from when the plants would be planted outside. You will have to consider that it will take 5 to 10 days for seeds to germinate, 3 to 6 weeks for seedlings to grow, and 1 to 2 weeks for seedlings to harden off before planting outside.

When you purchase seeds, be sure you buy seeds from reputable sources to help guarantee that the seeds are disease free. Seeds should be kept dry and cool until planting to ensure good germination. Seeds in foil packets will remain dry until planting, while seeds in paper packets can be kept in tightly closed cans or jars to reduce exposure to moisture.

Containers used for sowing seeds should be sterilized by rinsing them in a solution of one part bleach and 10 parts water. If you are re-using containers, they should first be washed in soapy water to remove all soil and debris. There are many choices for containers. Whatever type of container you use be sure that the container has adequate drainage. For small seeds, you can use plastic trays to sow seeds in and after germination thin out seedlings. For larger seeds it will probably be easier to plant in individual containers. Many use peat pots to start seeds indoors so that the entire pot can be planted outdoors at planting time.

When sowing seeds, use a soil mix that is loose, well-drained, and fine textured. After sowing seeds and watering, slip containers into clear plastic bags and place them in a warm location but out of direct sunlight. Since the bags will retain moisture, no additional watering should be necessary until after seeds have germinated. After germination, remove plastic bags and move to an area with bright light. Allow the soil to dry between waterings, but do not allow seedlings to wilt at any time.

Temperature plays an important role in the speed of germination and the percentage of seeds that germinate. The range of temperature that seeds will germinate at varies depending on the plant. In general, 65°F to 75°F, works for most plants. Typically, our homes are cooler than the temperature seeds will need to germinate. Germination heat mats can be found through many gardening supply companies. Containers can be set on the heat mat to increase the temperature around the seeds and improve germination.

For majority of vegetable plants, having light when the seeds are germinating in the soil is not needed. Light is usually needed after seedlings emerge above the soil surface. Containers can be placed in a window that receives plenty of light, like a south-facing window. If your house does not have a window with adequate light, supplemental light can be provided using fluorescent lighting. Seedling can be grown under fluorescent lights alone. When setting up lighting for seedlings, you will want to have the ability to raise the light as seedlings grow. Lighting should be positioned 6 inches above the plants and as seedlings grow, the lights should be raised.

When it is time to plant seedlings outdoors, plants can not abruptly be moved from indoors to the garden outside. To prevent any damage, they should be “hardened” before planting outdoors. Start gradually moving seedlings to an area with cooler temperatures at least two weeks before planting in the garden. When you first place seedlings outdoors, keep them in the shade and then gradually move plants into the sunlight for short periods each day. Gradually increase the amount of sunlight and time seedlings spend outdoors.

Once seedlings are hardened off, they can be planted outdoors with minimum damage. Transplant seedlings on a cloudy day or late in the afternoon to prevent sun damage. After planting in the garden, be sure to check seedlings daily and water when necessary to prevent wilting.
Starting vegetable seeds indoors can be an enjoyable and inexpensive way to pass along the cold winter months and when spring arrives you will have a head start on your vegetable garden.

Learn More!
• Visit our website at https://wayne.ces.ncsu.edu/. Click on “Lawn & Garden” on left side of webpage.
• “Like” us on Facebook to receive timely garden tips, ask questions, and learn of upcoming gardening events. www.facebook.com/waynecountygardening

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Jessica Strickland
Extension Agent
Horticulture
North Carolina Cooperative Extension
Wayne County Center
P. O. Box 68
Goldsboro, NC 27533
E-Mail: jessica.strickland@waynegov.com
Phone: 919-731-1520
Fax: 919-731-1511
https://www.ces.ncsu.edu/wayne

Written By

Photo of Jessica StricklandJessica StricklandExtension Agent, Agriculture - Horticulture (919) 731-1521 (Office) jessica_strickland@ncsu.eduWayne County, North Carolina
Updated on Mar 9, 2015
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