June 17, 2010
a gardener’s notebook
by Lee Reich
Last summer’s incessant rains and the late blight of tomato that the rains helped spread make this spring’s dry weather especially welcome.
Dry weather does, of course, mean that watering is needed. The vegetables are under the care of battery operated timers and drip irrigation lines. Water drips out the lines for a total of 20 minutes each day, spread over intervals during daylight hours. That might seem like lots of water, but it’s not; at each watering, water drips very slowly, at the rate of 1/2 gallon per hour, from emitters spaced 6” along the line running down each bed. Spreading the watering throughout the day replenishes soil moisture as plants use it up.
Beyond the vegetable garden, plants are on their own for water — except for newly planted trees, shrubs, and flowers. All these plants get off to a good start with some hand watering which, depending on plant size, may be once after planting or once a week the whole season. Hand watering can become tedious, but the plants love it and it’s crucial to getting them established.
A couple of cloudbursts last week got my gardening friends excited. Not to be a stick in the mud, but the rainfall was actually paltry. Yes, it did feel torrential at times, an effect heightened by the rumbling of thunder and dark skies.
A rain gauge tells all, though. In fact, only about a third of an inch of rain fell (0.39 inch, to be exact, at my house). Through summer, a garden needs, on the average, about an inch of rain per week. An inch of rain wets the soil to the depth of about a foot, which is where most plant roots reside. So that third of an inch of rainfall, following on the heels of weeks of dry weather, didn’t go far.
Then again, it’s still early in the season. New roots haven’t yet filled the soil to suck up all the soil moisture, and young plants and annuals haven’t grown enough new stems and leaves to pump that moisture back into the air. The soil is still a reservoir for last winter’s rain and snow. I planted some new berry plants in my berry patch yesterday and the soil there was still plenty moist. That’s because the ground there lies beneath a permanent blanket of wood chip and/or leafy mulch. Expect the soil to be drier beneath bare ground or lawn.
Rose de Rescht, basking in all that sunlight, is in spot where I haven’t yet mulched the ground. This is one old-fashioned rose that is supposed to blossom all summer long, but the blossoming has tapered. Perhaps Rose de Rescht is just taking a short rest from its burst of spring blooms. Perhaps soil is too dry. I’m going to water it by hand, then mulch. A gallon of water sprinkled slowly around the base of the plant is equivalent to an inch depth of rainfall (over a square foot), enough for another week of dry weather.
Nix on that watering; two-thirds an inch of rain fell in the hours since writing above. Let’s hope for sunny weather for a week, then another inch, total, of rainfall.