Starting Seeds: Where, When, and How

If you choose to grow your vegetables from seed, it’s essential to understand where to start them, when to plant them, and how to sow seeds to have the best plants for your garden.

Direct sowing vs. starting seeds indoors

Whether you can direct sow seeds into the planting bed or if you need to start them indoors depends on how long it takes the plants to grow to maturity and how long your growing season is.

  • If your vegetables have a shorter growing period than the local season, you can direct-sow them outside.
  • If your vegetables have a longer growing period than your growing season and are frost tolerant, you can direct-sow them.
  • If your vegetables have a longer growing period than your season and aren’t frost tolerant, you need to start the seeds indoors ahead of time.
When to Direct-sow?

Seeds that you can direct-sow fall into two timing categories based on their cold tolerance.

Seeds That You Can Plant Early in the Season

Some plants prefer cooler soil and air temperatures and may even survive a light frost. These cool-season plants can be sown directly outside before you can plant the rest and include leafy greens, peas, carrots, beets, Brussels sprouts, broccoli, cauliflower, parsnips, and turnips.

Seeds That Need to be Planted After the Last Frost

Warm-season crops need summer heat and aren’t frost tolerant. You can’t plant them until the last threat of frost has passed. They include peppers, tomatoes, cucumbers, pumpkins, squash, and sweet corn.

How to Direct-sow Seeds Outdoors

When it comes to sowing seeds directly into the garden, there are three things you need to consider:

  • Spacing between the seeds.
  • How deep the seeds are planted.
  • If the seeds need sunlight for germination or not.

After you prep the garden bed, place seeds at the correct spacing and depth listed on the seed packet. Gently cover them with soil and tamp it down lightly, if needed.

When to Start Seeds Indoors

The key to determining when to start seeds indoors is making sure plants have enough time to mature before the fall frost. Figure when they need to be harvested, and count backward from there, using their days to maturity, to determine when to plant.

Depending on the vegetable, this is typically four to eight weeks before the last spring frost.

How to Start Seeds Indoors
  • icon_number_1@3x Fill seed starting trays or plastic containers with pre-moistened seed starting mix.
  • icon_number_2@3x Plant seeds at their recommended depth, covering them lightly with potting soil if needed.
  • icon_number_3@3x Cover the containers with clear plastic or the accompanying plastic lid to keep the humidity high.
  • icon_number_4@3x Set containers on a seed starting mat or somewhere it is slightly warmer in your home, like the top of the refrigerator.
  • icon_number_5@3x Mist with a spray bottle to moisten the potting soil without dislodging seeds.