This is the most tantalizing time of year in the Northeast garden, isn’t it? Fifty degrees one day, 30 degrees the next. Bright sun and shorts weather, followed by frosty mornings and bone-chillingly cold rain. Snow is still a possibility at any moment. Ten years ago on April 10 a blizzard hit Connecticut, making 1996 the snowiest winter on record.
That fact, of course, seems to have nothing to do with 2006, which will likely go down as one of the warmest on record. Plant ecologists say winters in the Northeast are averaging three degrees warmer than a century ago, and this winter so far has posted one of the top five average temperatures of all time. It’s no wonder those same ecologists are saying lilacs bloom four days earlier than they did a century ago; grapes bloom six days earlier, and apple trees bloom a whopping nine days earlier.
All of this climate change may trick us into thinking we can start gardening earlier, and maybe we can. We do so with risks, though. Frost is possible anywhere in New England well into late May, and likely in northern New England until early June. It’s worth reviewing average “last frost” dates before we mention a few seasonal pointers: coastal Connecticut and Rhode Island, April 18; northwest hills and inland Connecticut and Rhode Island, May 9; Greater Portland in Maine, May 25; northern Vermont, June 18. That’s right. It’s a two-month range depending on where you live in the Northeast, which covers six USDA planting zones, from Zone 2-7.
Keeping that in mind, you need to know something about your own climate before you head out in early spring. For goodness sake, don’t set out tender plants yet — at least not overnight. Don’t remove all of your winter mulch yet either, especially not all at once. This can shock the tender shoots that may be forming just below the soil surface. Other don’ts: walking on soft lawns, rototilling wet gardens and raking moist lawns. All of these can do lasting damage to your soil and grass roots.
As for what to do: Finish pruning your fruit trees without delay and continue applications of dormant oil spray; remove the old canes of raspberries, thin the weaker canes and trim eight to 12 inches from the canes that remain; and begin raking lawns, as soon as they are dry enough, to remove dead grass and to lift snow mold and any leaves left from fall. This might help avoid unsightly dead patches that will need reseeding.
In some southern areas of the Northeast the forsythia will bloom soon, which means you should apply corn gluten to lawns and gardens to keep the seeds of annual weeds from germinating. The corn gluten also will provide a boost of nitrogen for the plants and help push out some spring growth.
That’s probably enough to think about for this week. The main takeaway point is to know your climate as well as possible, so the variances of spring don’t catch you off guard.
Paul Tukey
People, Places & Plants
