PLANTING DATES from THE GARDEN SPOT
by Mort Mather

"I planted too late." "I planted too early." What is all this concern over the timing of planting, anyway?

There are several things involved, the temperature at which the seeds germinate, the hardiness of the plants, the temperature in which the plants are happiest and the length of time it takes for the plants to mature. Peas, spinach and lettuce like to grow in cool weather and so will generally produce better if planted early. Their seeds will germinate in a soil temperature of 45 degrees. That is why we try to plant them as early as possible which is defined as as soon as the soil is dry enough to be worked.

The next planting date that I watch for carefully is when the soil is comfortable to walk on in bare feet. Since I go barefoot just about year around I'm not the best one to test by this method. What we are looking for is the right time to plant corn. Corn seed will germinate at 50 degrees but it will take three weeks to do so. There is considerable risk that if the soil is too cold, the seed will rot and have to be replanted. The reason some people plant seed that has been treated with fungicide is to keep them from rotting. I don't want those chemicals in my ground and I also enjoy the challenge of planting at just the right time. At 59 degrees the seed will sprout in 12 days, at 68 degrees in 7 days and at 77 degrees in 4 days. The reason for planting corn as early as possible is to get it as soon as possible, of course, but for some of the longer season varieties like Silver Queen it has to be planted early in order to mature before frost.

Winter squash also needs all of our short growing season but it can't be planted as early as the corn. It's minimum germination temperature is 10 degrees warmer than corn. In the event that the squash germinated and put a plant above ground before the last frost, the frost would kill it. Date of last frost is the last date to be concerned with in the spring.

In normal years I begin planting about April 15, plant the corn about May 15 and June 1 is the target date for the last frost after which I can plant squash and other warm-loving plants. June 1 is also the date for transplanting tomatoes, peppers, eggplant, melons and the like. This has not been a normal year so I have had to look outside rather than rely on the calendar.

There are a lot of vegetables that have shorter growing seasons and have a wide band of opportunity for planting. Lettuce can be planted as soon as the ground can be worked and any time after that until concern for fall frost becomes an issue. A lettuce that matures in 60 days can be planted 60 days before the first killing frost of the fall is anticipated. In my garden that is September 20. If I plant a 60 day lettuce about July 20, I will be eating lettuce from the garden in November. Sprinkle in a planting of radishes every couple of weeks from April to September to keep this crop spicing up salads over a four month period.

Make your own calendar. Each garden will be different depending on latitude, altitude, proximity to a large body of water, slope and some factors that you may never figure out. Events in my garden have been remarkable stable for 23 years. The past two have been a little different. Global warming or El Niño, it matters not. The calendar has always been no more than a tool to give me a target date for planting. What really matters is what is actually happening in the garden.

©June 8, 1998

Mort is a husband and father. He authored a book, Gardening For Independence and was named Environmentalist of the Year by Down East Magazine in 1987. He is a consultant for organizations. You can eat his organic produce at his son's southern Maine restaurant. His address is 802 Bald Hill Road, Wells, ME 04090.

mort@supak.com