Hurried spring planting may bring bummer of a summer
by C.L. Fornari
Last year I was at the garden center in April when a customer came up to me asking where the tomato plants were. "Oh," I replied, "it's far too early to plant tomatoes." This shopper frowned and said, "But it's nice out, and I want to do it now."
By the first of April, we're so hungry for spring that we're eager to have everything planted. Those first 60- and 70-degree days find many raring to purchase summer annuals or have landscapers put them in the ground. Unfortunately, it's too early.
Although most April temperatures are constantly warming, it's still possible to have a frost in the Northeast. Here are the average last frost dates: Boston, May 1; Washington, D.C., April 28; the suburbs north of New York City, May 10; and Philadelphia, April 14.
The possibility of freezing temperatures isn't the only reason that tender annuals and vegetables can't be put in the ground. In early spring, the soil is still cold, and many seeds won't germinate and plants won't grow roots unless the soil is warm.
Put bean seeds in the ground in April and they'll rot before the soil temperatures rise. Impatiens will sulk, turn yellow, and pack it in before the May warm-up.
Plants such as tomatoes, basil and eggplant don't need frost in order to be harmed. If the soil is cold, they won't grow at all, and if night temperatures are below 50 degrees, these plants are likely to die.
But it's nice out, and we want to plant now! Fortunately, there are many things that can go into the gardens.
Cool season annuals, such as pansies, osteospermum and alyssum, will do well throughout spring and summer, although they will last longer in Boston than in the humid heat of Philadelphia and Washington, D.C., once temperatures rise.
Cool crop veggies such as broccoli, peas and Brussels sprouts can be planted in April. Lettuce seeds germinate well in cold soil, and this makes it not only perfect for kitchen gardens, but also as early spring fillers for window boxes and pots.
Shrubs can be planted in April if the soil is not too wet. Nurseries in Philadelphia and Washington, D.C., are well stocked by the first of the month, and Boston garden centers will have shrubs and trees by the second week of April.
There is one note of caution, however. If the shrub or tree looks more developed than those in area landscapes at that time, it's possible for that plant to be damaged by a late frost.
Perennials can also be placed in the spring garden, but use the same watchfulness with plants that already have summertime flowers and foliage.
April is a good time to discuss this year's garden goals with your landscapers as well. The more information they have about how you'd like your garden to look, the better able they are to plan their season with you in mind. So get prepared for the growing season instead of hurrying it along.
C.L. Fornari is a writer, professional speaker, and the host of GardenLine, a weekly call-in program heard on WXTK-FM (95.1) radio on Cape Cod. She's the author of several books, a volunteer master gardener and a landscape consultant. Her website and blog can be found at gardenlady.com and wholelifegardening.com.