Seed starting

The main reasons for starting seeds indoors are to get a jumpstart on the growing season and to grow a greater variety of vegetables than would be available at the nursery. Before selecting vegetable varieties, check the seed packets to determine the number of days until harvest to make sure you select varieties that will ripen before the first frost in the fall. Transplants require several weeks to grow, so consult the seed packet to find out how many weeks each variety will need before being transplanted out. Using the average last spring frost, determine the best time to start seedlings indoors by counting back the number of weeks needed to grow seedlings that can withstand the various spring soil temperatures.

Once the seed starting date has arrived, gather all your seed starting supplies:

• Seeds to be started
• Containers to sow the seeds in (2-3” wide)
• Germination mix or peat pellets
• Water (preferably warm)
• Plant tags to keep track of what was planted in each container (I like plastic tags the best)
• Black sharpie marker (other colors fade quickly) to write on the plant tags

Moisten the germination mix (“soil”) with warm water. Fill the container to within 1 inch of the top with damp germination mix (gently press the mix with your fingers or knuckles to compress the “soil” slightly). Make an indentation in the soil about two times larger than the seed (depth and width). Sow one seed into this space then cover with a thin layer of the germination mix. Depending on the seed size, I sow one large seed, two medium seeds, and a pinch of small seeds per container. Be sure to scatter the seeds uniformly and with enough space to allow seedlings to grow evenly without competing with other seedlings.

Most seeds germinate quickly provided that the “soil” is kept evenly moist and the soil temperature is 65-75oF. To help maintain a high humidity level during germination, cover the containers with a plastic dome until seedlings emerge. If the soil temperature and moisture levels were optimal and you do not see any signs of life within 10-15 days of sowing the seeds, it may be time to start over. Some seeds, especially peppers and eggplant, take longer to germinate. Patience is a virtue for these plants.

Once sown, record the name of the plant and the date on a plant tag and insert it into the container – repeat for each variety. You may find it helpful to have a journal to help keep track of the dates the seeds were sown, when seedlings were transplanted, and when the plants were planted outdoors (click here to see my online journal).

I place my germinating seeds under fluorescent lights (more on this later) but you can also place the containers near a window. While seeds do not require light to germinate (check the seed packet for light requirements during germination), it is always good to keep them near a light source so they do not grow spindly once the seedlings emerge – which can happen very quickly.

There is no need to use fertilizers during germination as seeds contain all the nutrients it will need to germinate, send up a stem, and to form the cotyledons. Since soil-less mixes contain very little nutrients, the seedling will require [very dilute] liquid fertilizer around the same time that the first true leaves begin to form.

It may be necessary to thin the seedlings after the first true leaves form (refer to the seed packet for information on spacing). To do this, remove the weakest seedling by cutting the stem close to the top of the soil – do NOT pull the seedling out of the soil. Thinning the seedlings is usually the toughest part as most will look healthy and strong. If this is the case, keep the seedling that is in the center of the container and remove those close to the edge. I do not thin onions, herbs, or lettuce…unless they appear to be overcrowded and not growing well. You will be glad that you thinned the seedlings when you are awarded with a large harvest.