By Dawn De Busk
Starting seeds allows gardeners to grow plants indoors before the weather is agreeable enough for an outdoor garden. It’s giving the plant a boost, some protection from finicky Mother Nature.
Starting seeds indoors involves a lot more than just plopping seeds into the soil. Master Gardener Nancy Donovan provides some valuable tips for partaking in this spring ritual.
B-News: How soon should people be starting seeds indoors?
Donovan: The decision of when to start seeds depends on two factors: 1.) What are the guidelines on the seed packets that you have purchased from reliable sources, and 2.) What is the average last spring frost date? According the Old Farmers Almanacthe average last spring frost for Bridgton is May 14. Another source for information about frost dates is the National Gardening Association. Personally, I am more comfortable delaying the day that I plant vegetables outside. (Currently the vegetables I grow include tomatoes, cucumbers, carrots, beets, Italian string beans, and squash). I wait until June 1 to plant my seedlings. It seems that every year I hear that some decide to place seedings in the garden earlier due to warm weather and then they lose the seedlings due to a frost. When I took the master gardener class there were a lot of moans from the gardeners that had first hand experience with planting seedlings too soon.
B-News: Which seeds are appropriate to start in early May?
Donovan: According to the guidelines from the Maine Cooperative Extension, the most common plants to start as seeds indoors include tomatoes, peppers, eggplants, cucumbers, broccoli, Brussel sprouts, cauliflower. The Maine Organic Farmers and Gardeners Association (MOFGA) also has an outline of plants and when to start seeds indoors that is available online.
B-News: Some people have heat lamps for starters — are those necessary or do sunlit windows work?
Donovan: Growing seedlings in sunny windows is not recommended for a couple reasons. In Maine we still have shortened daylight, and we often have days that are cloudy or rainy (or snowy). Also, while the days may be warm, the nights can still be quite chilly which is definitely not conducive to happy and healthy plants. The best way to start seeds indoors is to use supplemental lighting. A great source for guidance is Bulletin number 2751 titled “Starting Seeds At Home” from the University of Maine Cooperative Extension Service, which is available online. The document provides information about using fluorescent lights, LED lights, grow lights, and also how to build a lighting system. Again, the document is available online.
B-News:Where do you recommend people go to purchase seeds and gardening supplies?
Donovan: We have so many good places here in Maine that I do not have a specific recommendation. The only comment I have is that buyers should make sure the seed packet says that the seeds are dated for 2021. Also, there are organic and non-organic seeds. Regarding supplies, the only recommendation I have is to buy from local businesses as much as possible.
B-News:What should people do to keep soil from getting too moist or too dry for seeds to germinate?
Donovan: Seedlings should be watered thoroughly and then not again when they are almost dry. Watering too much might result in the growth of fungus.
B-News: Is there a way to remedy seeds that won’t germinate?
Donovan: The best way to promote germination is to use a sterile, soilless mix. There are seed-starting mixes that can be purchased, or it is also possible to prepare your own. Personally, there are other things I would rather be doing and so I choose the easy way. I purchase a prepared mix. The only caution I have is that garden soil should not be used as it may contain weeds or pathogens. It also compacts more than prepared mixes. And then there is the pH thing… a very important thing that I learned the hard way. You may also notice that prepared mixes tend to repel water and so the Maine Cooperative Extension guidance is to use warm water in the mix when planting the seeds “…until it is uniformly moist, but not oversaturated.” To keep the soil moist during seed germination it is advised that the growing container be covered with a clear plastic dome or with clear plastic.
There are several reasons that some seeds will not germinate. These include overwatering, underwatering, too cold, too hot, not enough air circulation. The best chance to have successful germination is to ensure a good growing environment. Another important factor about growing successful seedlings is that the first set of leaves that emerge from the soil are called the cotyledons. The cotyledons are actually part of the seed and serve as a source of food for the seedling. The next leaves will look different form the cotyledons and are called “true leaves.” When the seedling has grown enough to see one or two sets of “true leaves” then it is time to plant them into larger containers.
B-News: What do you think about using cardboard egg cartons for a seed starter tray? Any other suggestions?
Donovan: I have read about using egg cartons to start seeds, but have never done it myself. As I read a few reliable sources, the main principles are the same. Make sure there is good drainage and use a sterile mixture and don’t overwater or underwater.
B-News: What is the most common problem that novice gardeners run into when it comes to starting seeds indoors?
Donovan: The most common mistake is overwatering. Of that I have been guilty. I actually note on a calendar when I water a plant in my house so that my plants do not experience drought or pooling. There is a problem called “damping-off” that is caused by a fungus that can develop in warm, moist environments. It can be identified by a rot that occurs at the base of the seedling stem that results in the plant collapsing. Again, using a sterile soilless mix and watering the plant thoroughly and then waiting until it is almost dry before watering again gives the seedling its best chance.
B-News: Which seeds should NOT be started indoors?
Donovan: For this answer I referred to the University of Maine Cooperative Extension Bulletin 2751. The advice is based on the fact that some seedlings do not do well when transplanted. These include beans, beets, carrots, corn, peas, spinach, lettuce, turnips, and zucchini.
B-News: Do you recommend soil testing? Where?
Donovan: I always recommend soil testing before planting. When I built my home here in Bridgton, I did not have a lawn put in because I am not fond of mowing. For my back yard I thought it would be really nice to grow low-bush blueberries for myself and for the birds. I purchased 6 plants (not inexpensive, at least for my budget) and planted them in my soil. Sadly, they did not produce any berries. To be totally honest, they died. When I asked someone at a nursery what I may have done wrong, I was asked about the pH of my soil. I think my response was something like “The what of my soil?” As I now know, blueberries thrive in acidic soil. A subsequent soil test revealed that my soil was 7.0 (not acidic). Those beautiful plants would have had a much better chance at survival if I had performed a soil test and applied amendments based on the recommendations from the soil lab before diving in!
The University of Maine Analytical Lab and Maine Soil Testing Service will test a sample of your soil that you can send to them in a box they provide. The soil sample test will record the nutrient levels, the pH, the amount of organic matter, and recommendations for nutrients to be added as well as fertilizer needed and which formula to use. While the soil test purchased at gardening center can measure pH and some nutrients, I have really benefitted from the analysis performed by the Maine Cooperative Extension as I can speak directly with them and they will tell me exactly what I must due to fix my soil. The phone number is 207-581-3591 and the website is https://umaine.edu/soiltestinglab/ The cost is $18.00
After receiving the results of my soil test (every three years), I am in the process of planting perennial beds that should thrive in my soil. In addition to enjoying the many colors afforded by perennials, I also have the goal of supporting pollinators (bees, butterflies, moths, etc) which have been shown to be decreasing. The bees are especially needed to pollinate the garden. And, now that I have learned during the master gardener volunteer classes about the importance of planting flowers native to Maine that support pollinators, I am focused on planting seeds and plants that are native to Maine. Lawns do not support pollinators,
and the herbicides and pesticides are the enemies of pollinators
It may be of interest to readers that the Maine Cooperative Extension has established a Pollinator-Friendly Garden Certification Program. There is an application form at https://extension.umaine.edu/gardening/pollinator-garden-certification/
The major requirement is that 70% of the plants in the area being certified are native to Maine. There are many sources to assist in the determination which plants/flowers are native to Maine. Last year I counted 17 bees on one plant. It was a joyful moment!