Start Seeds Indoors to Get a Jump on Spring—Here's What You Need to Know

When spring rolls around after a long winter, you don't want to waste a minute of that warmer weather to get growing! Starting seeds indoors is a time-honored way to get a jump on the season. If you want to try just a few easy-to-grow seeds, it can be a pretty quick project and you can even get them growing with what you have on hand; no need to buy any special supplies. Or, if you're looking for more of a challenge, you can scale up accordingly. Here's what you need to know to successfully start seeds inside for planting outside once temperatures stay above freezing.

If it's your first time starting seeds indoors in winter, it's best to go small. Pick just one or two types that are easy to grow from seed like these favorite annuals:

Test Garden Tip: Look on the seed package label to find the number of weeks you're supposed to start seeds indoors before the average last frost date. It usually takes about six to eight weeks to give your seedlings a head start on spring, so count backward from your area's frost date to figure out when you should start your seeds indoors.

Seed flats ($6, The Home Depot) are super easy for planting indoors. But you can dig through your recycling bin, too. Just remember to punch a drainage hole in each container before planting. Cardboard egg cartons work well, but you can also repurpose cut-down milk jugs, yogurt cups, and disposable pans. You can also make your own seed starter pots from materials like newspaper and paper mache.

Even though the planting instructions on the packet might vary, you'll need the same supplies to start any seeds indoors. Here's what you'll need:

• Seed-starting pots with drainage holes (or DIY seed starting pots)
• Seed-starting mix ($5, Lowe's)
• Labels for each pot ($6, Etsy)

Add seed-starting mix to your pots until each is filled to about a half-inch from the top. Then, follow the seed packet instructions for planting. Some will suggest making a shallow hole in the center of the potting mix to put the seeds in and others will say to add seed right on the surface.

It's best to add 2-3 seeds to each pot, in case one doesn't sprout. Once you've sown the seeds, cover them with potting mix and mist each container enough so that the potting mix is damp, but not drenched with water. The water will also help the potting mix settle around the seeds.

Label your pots so you know what's growing in them. Loosely cover the pots with clear plastic wrap, which helps maintain humidity and warmth.

Place your seed pots in a location that's warm and free of drafts, but not in direct sun. The top of a refrigerator works well because it's out of the way and it gives off just enough heat around it to help the seeds grow. The ideal temperature is about 75°F but no hotter than 90°F. Once the tiny seedlings emerge, remove the cover and move them into sunny window. They need about 12 hours of light a day, so you may need to supplement with grow lights.

You started your seeds. Their first leaves are poking up in the pots. What do you do next?

After seeds have sprouted, take off the plastic wrap or other covering so they can breathe a little.

As the seedlings make their presence known, they need their space. Keep the ones that look healthy and strong, and snip the rest so there's just a single plant per pot.

After they're about two inches tall and have a couple sets of leaves, your seedlings need an upgrade. Transplant them into larger containers, this time in regular potting mix instead of seed-starting mix.

Don't let the seedlings dry out! Misting them is the best way to give them a drink: Don't put them under a faucet or hose, because the water pressure can wash them right out of their containers.

Before you can move your seedlings out into the garden (keeping your frost-free date in mind), you need to give them a few days to slowly get used to life on the outside. That's what's known as hardening off your plants. To do this, place the seedlings outside for a short time in a protected spot (think an hour or two). Every day, increase the length of time you leave them outside until they can remain outdoors all day.

Sometimes, you might notice your sprouting seeds struggling. Here's a couple of common issues to watch out for and what you can do to avoid them:

Wilting seedlings might be a sign of damping off caused by a fungus that sometimes appears because of overwatering or overcrowding. Or you may see tender young leaves wilting when soil gets too dry.

Solution: Make sure you use fresh seed-starting mix that has been sterilized to kill any fungi. If potting mix feels dry to the touch, mist with water and check back later in the day to see if your seedlings have perked up.

Not enough light can result in stretched out seedlings that are desperately trying to find more brightness.

Solution: Use a grow light or move your plants into a better lit spot.

Starting seeds indoors will let you have a lush, beautiful garden for a fraction of the price of picking up new plants at your local garden center. After the last frost of the season has passed, your seedlings should be ready to go out into the garden. If you're successful, you'll soon have healthy, towering plants that look nothing like the tiny seeds they came from.