The Cool Truth About October: Shorter Days, Longer Harvests

No bolting here. With the onset of cooler temperatures, gardeners can enjoy an extended lettuce harvest.
No bolting here. With the onset of cooler temperatures, gardeners can enjoy an extended lettuce harvest. (By Bill O'leary -- The Washington Post)
By Barbara Damrosch
Special to The Washington Post
Thursday, September 20, 2007

When T.S. Eliot wrote "April is the cruelest month," he might have added, "October is seriously underrated."

Consider those two months. We expect from both a temperature range midway between hot and cold, with unpredictable doses of either. But gardeners, especially, embrace April with exaggerated hope and cheer, oblivious to the imminent onset of blistering heat, drought and bolted lettuce. By October many edge wearily and even gratefully into the shadow of oncoming winter, forgetting to enjoy the gardening year's best weather.

Poke your head outside the cocoon of artificial lighting and controlled indoor temperature, and you'll better understand the rhythm of the seasons' lag time, a planetary dance in which reality and symbol rarely mesh. What we call summer solstice (around June 21) runs about two months ahead of the year's hottest weather, and the winter solstice (around Dec. 21) two months ahead of its coldest. "As the days begin to lengthen, the cold begins to strengthen," the old saying goes.

The number of daylight hours on the spring equinox (around March 21) is the same as that on the fall equinox (around Sept. 22), but while the sun in March seems feeble, in September it feels strong, thanks to the slowness with which the earth absorbs and releases the sun's heat. In spring the warming of the soil surface can lag a month and a half behind that of the air on a mild day, and six feet below, the lag can be as much as three months. In fall, the ground is comparably slow to chill.

This all adds up to fall gardening nirvana. The earth is still warm, even if you start the day with a thick sweater. Pest insects are bundling themselves up in pupae to hibernate or seeking refuge underground. The shortening days let you get away with feats impossible in spring. Lettuce and spinach, whose impulse to go to seed is triggered by lengthening days, do not bolt cruelly, but bide their time, allowing a gloriously long harvest. Arugula loses its harsh bite. Carrots, beets, turnips, parsnips and Brussels sprouts begin the magical sweetening-up that comes with the cold.

As maples turn scarlet, Tuscan kale glows with the deep green of chlorophyll. By the time such summer crops as tomatoes, cucumbers and melons have frozen or lost their flavor, far more crops have reached the perfect moment. You're then ready to compost all those tired vines and embrace the garden's benign season.

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