Starting Seeds Indoors

Starting Seeds Indoors

Many vegetables are easiest to grow by planting seeds directly in the garden, but some, such as peppers, tomatoes, melons, and eggplant, need a head start indoors. 

Starting seeds isn’t difficult, but it takes time and attention. The payoff is an abundance of fresh, delicious vegetables in a few weeks. Here are the basic steps:

As a general rule, most seeds should be planted about six weeks before the last average frost in your area. 

Step by step guide for successful seedlings

  1. Fill containers with a lightweight seed-starting mix. Nearly any container will work if it has a drainage hole, but many gardeners find it easiest to use celled seed trays, which are uniform and easy to handle
  2. Moisten the seed-starting mix so it’s moist but not soggy. One easy way to do this is to water the containers thoroughly, then let them drain.
  3. Plant the seeds according to the depth indicated on the seed packet. Tiny seeds should be barely covered, while larger seeds are often planted at a depth of about 2.5 cm. 
  4. Cover the containers loosely with clear plastic wrap, which will provide humidity that seeds need to germinate. 
  5. Water lightly as needed to keep the seed-starting mix moist but never soggy, as waterlogged soil can contribute to mold and fungal diseases. It’s usually easiest to water from the bottom. 
  6. Place the containers in a warm location such as the top of a refrigerator or other warm appliance. Alternatively, place the containers on a heat mat. 
  7. Remove the plastic and move the containers to bright light as soon as the seeds germinate. Don’t rely on a sunny window, which may be too cold at night and too hot during the day. A fluorescent light turned on for 12 to 16 hours per day ensures the seedlings receive sufficient light.
  8. At this point, seedlings need cooler temperatures of around 15 C°.
  9. Feed the seedlings using a water-soluble fertilizer mixed to half strength when the seedlings have two sets of leaves. Repeat every week.
  10. This is also time to thin the seedlings to one healthy plant per container. Snip the smaller seedlings (don’t pull them).
  11. As the seedlings grow, you’ll probably need to move them to slightly larger containers until they’re ready to be planted outdoors.
  12. Harden off the seedlings before you plant them outdoors. Put them in a protected sunny spot for two or three hours. After a couple of days, gradually increase the amount of sunlight and outdoor time.
  13. Work a vegetable and herb mix into the top 2 to 4 cm of soil before planting seedlings outdoors. Vegetable and herb mixes are formulated to support strong, healthy growth.


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