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How to grow seeds indoors

It might still be the dead of winter, but spring is just around the corner. Get a jumpstart on your garden by learning how to grow seeds indoors. We’ll show you how in five easy steps.

Seedlings growing indoors

Growing seeds indoors doesn’t just give you a jumpstart on the gardening season, it also can be a huge money-saver when done right.

Starting seeds indoors can be extremely beneficial if you plan to grow several plants of one type or want to try a variety that isn’t typically found in a garden store. However, if you are only planning to plant one type of variety, it may be less expensive to buy a transplant at the garden center rather than growing from seed. Some of our favorite seeds to try include lettuce, peppers, heirloom tomatoes and basil.

Once you’ve determined what plants to grow from seeds, begin assembling your supplies and growing timelines.

Seed-sowing supplies

In addition to purchasing your seeds, a few basic inexpensive supplies are needed to sprout seeds indoors.

Containers. Choose a container that allows extra moisture to drain. Colleen Plimpton, author of Mentors in the Garden of Life recommends using recycled plastic six-packs from last year’s annual purchase to help save money. You can also purchase peat pellets or make a DIY container from yogurt cups or egg cartons.

Soil. Seedlings need soil that can hold moisture evenly and allows plants to grown quickly. Plimpton suggests using seed starting soil — not potting soil.

Lighting. Look for a south-facing window that provides direct sunlight, but doesn’t get too hot. Seedlings can be placed on a window sill or small table. If natural lighting isn’t an option, try an artificial source like plant lights. The Utah State University Extension suggests using inexpensive shop lights attached to a timer. Hang lights 2 to 4 inches above containers and adjust the height upward once seedlings begin growing.

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Planting seeds

Determining when to plant seeds indoors depends on when you want to plant them outside. Contact your local university extension office for information on the best planting time for your region. The seed packet should have the length of time it will take for the plant to sprout, which you can use to calculate when to plant the seeds.

Check the packet to see the depth the seeds should be planted at and whether they should be covered with soil. Moisten soil before planting seeds. Plimpton suggests using warm water to let it soak faster. Plant one to three seeds per pot. Make sure the soil thoroughly drains so no standing water is left. Cover the container with plastic wrap to create a greenhouse effect and lock in moisture. Move the container to warm area.

Taking care of seedlings

Michael Podlesny, owner of Mike the Gardener Enterprises, a seed of the month club, recommends placing planted seeds by a window that receives sunlight first thing in the morning to maximize the amount of sun it receives. “Once the seeds sprout, do not remove the dome that is being used to create the ‘greenhouse’ effect until they are at least 2 inches tall, taller if possible” says Podlesny.

If multiple seedlings sprout in the same pot, prune the weakest ones before they reach 2 inches tall. Keep plants moist but be careful not to overwater.

Harden off plants

Seedlings need to be “hardened off” and acclimated to the outdoors before being planted outside to reduce transplant shock. One to two weeks before planting the seedlings, place them outdoors during the daytime in an area that is protected from rain and wind. Bring the plants inside before it chills down at night. Ideally, harden off plants once temperatures hover around 50 degrees and the danger of frost has passed.

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Plant and protect

Once seedlings have hardened off and are ready to plant, dig a hole and add compost to the soil mix. Plant seedlings about the same depth as in the original container. Tomato plants can have their bottom leaves pruned off and planted several inches deep. Water well and add mulch around the base of the plants for additional protection. Protect transplants from frost by covering them with an old sheet at night, removing it in the morning.

The most important part about growing seeds indoors is to experiment and figure out what works best for you in your environment. Keep track of your progress by writing down what worked (or didn’t) or try keeping a gardening journal online using, a Web-based gardening tool that can help plan your garden virtually.

More gardening tips

Creating an indoor herb garden
6 Houseplants you can keep alive
How to garden for a healthier diet

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