GARDENING GURU JERRY BAKER said plants were like people, and I believe seeds are, too. Some seeds grow easily under many conditions, like your friend who thrives no matter what life gives her. Similar to your black sheep cousin arriving on your doorstep, some seeds germinate unexpectedly by the back steps, in the driveway gravel, or in the compost pile. Others are as fussy as your little sister, needing precise coddling to get moving.
This last group of seeds generally requires starting indoors well before planting out in the wide world. The tiny print on the seed packet gently suggesting “start indoors eight to ten weeks before planting out” is a warning to plan ahead. Other crops, such as tomatoes, germinate easily but take a good three months or more to fruit, so giving them a head start indoors assures production in the current calendar year.
After assessing which seeds need what conditions, assemble your gear. I like to use a soil-less mix, containing peat, perlite and vermiculite, specially formulated for seeds. It’s lightweight, drains well, and contains no killer pathogens. You can make your own mix, and even pasteurize it in your kitchen oven, but the stink and mess can substantially reduce household harmony. I also use professional grade plastic cells, those familiar “six packs” seen in nurseries, but a wide array of food containers, cleaned and given drainage holes, may work just as well. Containers can also be fashioned as soil blocks, made from peat or coir, or created from newspaper.
Seedlings need light, a tricky proposition if you rely on a windowsill location here in sun-deprived upstate New York. While the daylight is incrementally getting longer, cloudy days and low light intensity tend to leave seedlings spindly and weak. Luckily, we’ve got artificial options. Swanky “growing systems” with stands, trays, and lights are attractive, durable and easy to use. Still, they’re too costly for thrifty me, who relies on classic “shop lights,” the four foot fixtures with two fluorescent bulbs. Newer T-8 bulbs are longer lasting and more economical than the older T-12 type, while LED bulbs are more efficient still, and seedlings of most plant species will thrive under all of them. Special “grow lights,” which produce more red and far-red light, are not needed for seedlings, but are a must if you’re trying to grow flowering plants under lights, such as African violets or orchids.
A swift kick in the bottom gets me motivated on Monday morning; a seed’s equivalent is bottom heat. Put your seed tray on a heat mat, plug it in, and watch germination time drop as the seeds pop. Put the tray on a warm surface – the top of the refrigerator or furnace – to get the same effect. While many seeds will grow at normal room air temperatures, extra root-zone warmth helps. The biggest danger is over-exuberance. If your ‘Lemon Gem’ marigold packet advises six weeks start time, plant them on April 1, not February 1. Seedlings get cabin fever just like the rest of us.
To contact David Chinery, horticulture educator for Cornell Cooperative Extension, email email@example.com