A spike and surge in both interest and sales of garden seeds occurred in March and April of 2020 at the onset of the Covid-19 pandemic. Interest in vegetable gardening and pollinator gardening helped drive purchasing of seeds that continues into 2021. Many who had never tried seed starting took up the rewarding experience as stay at home orders were put in place across the country. A whole new generation of gardeners sprouted growing homegrown produce and sowing flowers for use around their home. With the interest now all you “seed” is love. So how can you improve success with your seed sowing and young fledgling seedlings leading up to spring 2021? Here are some insights that may help you in the process.
The proper time to sow seeds for seedlings depends on when plants may safely be moved outdoors. It depends on the plant from 2-3 weeks for something like lettuce to 8 weeks for peppers or tomato plants. Consult with the back of the seed package for that information. A common mistake is to sow seeds too early and then attempt to hold the seedlings back under poor light or problem temperature. You don’t want tall spindly plants too weak for the garden. I have found that tomatoes as an example when sown 8 weeks before planting time will get a little long. It’s OK, if hardened off properly you can “deep plant” them by submerging part of the “hairy” stem in the soil at the time of planting outdoors resulting in a deeper and more aggressive root system. The plant will develop roots along the stem in the soil. Again using tomato seeds as an example they take 5 to 10 days to germinate and begin growing. They should be started around 6 to 8 weeks before the last frost date. In West Michigan I usually plan for right after Mothers Day using May 10 as guide. Then you have time to harden them off (moving in and out for short periods of time and protecting from the wind) until they are ready to be planted outdoors for good sometime between May 15 and Memorial Day. That means March is a good month for starting tomato seeds inside targeting March 15-30 as an example. (click on images to enlarge)
Some seeds germinate and grow so quickly that there’s no reason to take up indoor space to start them early. Corn and beans are good examples. Outdoor soil temperature is the key. If the soil is warm (above 60 degrees soil temperature) it’s easier to sow those seeds directly outdoors. Squash, cucumbers, and melons (curcurbits) are good examples. You can start them indoors and its fun, just don’t start too early, a few weeks before hardening and planting outdoors should suffice. Sow large seeds like cucumber, melons, corn, beans) directly into small peat pots. Sow two or three seeds per pot and later thin to allow the strongest seedling to grow. If you don’t want to have transplant from a seed flat into pots you can starting your seeds in peat pots (formed from peat moss) and it offers you the chance to skip the transplanting step. Peat pots can be planted directly into the garden once your seedlings are ready. If seeds are tiny, like lettuce and herbs like basil, they can easily get lost if you direct sow them in the garden. The problem is once they germinate, it’s hard to separate the weeds from the desired plants. I would start them indoors to give them a jump start in the garden.

Sow seeds thinly and uniformly in the rows by gently tapping the packet of seed as it is moved along the row. Lightly cover the seeds and press down gently to ensure good contact between the seed and the seed starting soil. If you are using some seed leftover from last year, select 10 seeds and place them in a damp wrapped paper towel, place the towel in a resealable plastic bag to retain the moisture. Within 5 to 10 days you will be able to tell the viability of the seed, if 8 sprout as an example you have 80% germination rate.
A plastic cover or even plastic wrap loosely over the flat can initially be used for warmth and humidity after you have sown the seeds. Be prepared to tent and vent the plastic once the seeds germinate and begin growing. Once the majority of the seeds have germinated and are pushing against the plastic, remove the plastic. Once the seedlings are to a height of a couple inches the light factor will be critical. Heat and moisture are needed for germination. Light and moisture are critical once the leaves start to develop. Planting depth is usually about twice the diameter of the seed which isn’t much. Have you seen how small some of those seeds are! On the back of the seed packet, it will indicate how deep to plant individual varieties of seeds. Remember good soil to seed contact, warmth, (65°-75°F soil temperature is best for germinating seeds of most plants) and moisture/humidity are the keys to good germination. (click on images to enlarge)
Sometimes a helping hand is best given by explaining the mistakes that can be made. We learn from others mistakes right? Here’s some thoughts on what not to do:
- One of the biggest mistakes people make when starting seeds is starting the seeds too early. Stressed-out plants are more susceptible to pests and disease. Consult the package for timing, that information is there for a reason!
- Not providing enough light (they will stretch and be leggy) Suspend lights so that you can raise the lights higher as the seedlings grow. Keep the lights as close to the seedlings as possible without touching them (2 to 3 inches). When seedlings first appear, keep the lights turned on for 12 to 16 hours per day.
- Use a good quality lightweight seed starting soil and make sure it remains moist but well drained. For seeds to germinate, keep the soil warm, about 65 to 75 degrees Fahrenheit. These mixes are fluffy and light, root systems thrive, and they meet the criteria of “moist well drained” soil so there is less chance of fungus problems like damping off. Once the seedlings are growing some air movement will also help.
- Proper planting depth is usually provided on the seed packet. If there is no information on the packet, the rule of thumb is to plant seeds two times as deep as their size. In other words not deep at all! Light is important so determining depth can be a challenge, but if you are not sure, err on the shallow side.
- Don’t skip the step of “hardening off” When your seedlings are large enough to plant outdoors, you need to prepare them for the transition to the garden outdoors Hardening off gradually prepares them for outdoor conditions like wind, rain, and sun. The hardening-off process is simple, though it can be time-consuming; it involves exposing your plants to the elements gradually. Progressive, incremental exposure of young plants to sunlight and outside weather, will acclimate them to the growing conditions of the garden and help make them strong, sturdy and more productive once they’re finally planted outside. When initially setting them out for periods of time provide a wind block and some shading from the direct sun.
Many different containers are used for seed starting. Empty toilet or paper towel rolls, newspaper, egg shells or egg cartons, Dixie cups or disposable coffee cups, even muffin pans or citrus fruit can be used. I like using sterile clean seed flats and trays or peat pots or expandable peat Jiffy 7’s that expand as they get moist and can be planted directly into the garden when the time comes.
Lately there is a lot of social media interest in “milk jug” sowing where seeds are sown in the bottom half of a milk jug and set outside long before the last frost date. Rinse out the milk jug and punch four drainage holes into the bottom. Cut the milk jug horizontally at the bottom of the handle working your way around the circumference. Essentially you are cutting the jug in half and putting soil in the bottom (recommend Ocean Forest soil) because in this process we are not using a typical “seed starting soil”. Once the seeds are sown the jug is put back together taping it with duct tape. The top lid is thrown out and left off (ventilation). The jugs are labeled with the variety and the date sown and set outside. I’m going to try it this year, I have never done it so I can’t give you a testimonial. It’s inexpensive, sounds like fun so worth the shot. Nothing ventured nothing gained. You can find groups in social media (Facebook) that you can join and follow the progress. Now all you “seed” is love. (click on images to enlarge)