Weather seems to be a never-ending topic of discussion in New England. This summer's constant rain followed by that horribly humid hot week gave us plenty to complain about, didn't they? What a relief to finally get some truly beautiful balmy summer days. This morning, however, my thermometer read 55 degrees, pretty chill for the 17th of August. Is Jack Frost about to return from his summer vacation? If so, I feel cheated.
I've been browsing through my garden diaries, checking up on the first fall frost in past years. You'd think a garden columnist would keep a good garden diary, but unfortunately my efforts in this direction are pretty pathetic. Once I actually get out in the garden, writing down what's going on there is replaced by the real thing, planting, weeding, watering, enjoying.
Of the dozen or more incomplete garden diaries I've started, few get as far as September, so trying to discover past dates for Jack's arrival isn't easy. It wouldn't prove much even if I could since frost-nipped plants can occur as early August 26th (that year, although unrecorded in a diary, was so upsetting I'll never forget it) or as late as the third week in October (that was in 1981).
A frost, unlike a freeze, doesn't necessarily reach every nook and cranny on a property. Smart gardeners pay attention to which areas of the yard are prone to a rime of white in the early morning, and have planted their vegetables in a spot unlikely to be plagued by those "undeserved" frosts.
Once we moved our vegetable garden from the meadow down to the back yard, beautifully protected on three sides, we can get two or three frosts on the rest of the property and still have ripening tomatoes and peppers, sometimes for as much as a month. Uprooting tomato plants full of green fruit and hanging them upside down in the shed or garage is another way to beat Jack, as they will continue ripening for many weeks.
The whys and wherefores of the evening dews and damps and that thing called a dew point can be pretty confusing, but helpful in predicting frost. Dew is the result of water condensation. As air cools it is able to hold less and less water vapor. When it can hold no more, the water vapor condenses, forming dew, and the temperature at that exact moment is the dew point.
When dew forms it releases energy and that energy keeps the temper- ature near the ground at the same level as the dew point. Therefore if the dew point is hovering in the low 30s, prepare for frost. If the humidity is high, so is the dew point. A night of dry air, no wind and clear skies indicates a low dew point and you'd be wise to cover all the tender vegetables with blankets or buckets.
So often we have weeks of glorious balmy weather after the first frost that it's really worth protecting plants. We have yet to be hit with the first fall frost so I haven't a photograph of that sad sight - blackened, frost-bitten plants, so I guess I'll just find some old autumn photographs for this column.
A maple's first Autumn colors Getting out the old cider press
