(8/9) A Gardener’s 2nd Chance

After a long, hot, dry summer I can’t wait for the cooler weather and another chance at heat intolerant vegetables. I couldn’t help myself; I sneaked a hopeful look at NOAA’s long-range forecast for this fall. I’ll let you decide how much stock to put in a forecast for 2½ months into the future, but NOAA indicated a 50% chance for more of the same – warmer than average.

This year may be the one for a great fall garden, except long range forecasts don’t account for sudden cold snaps and rain occurring as a few deluges spaced by drought. By now any gardener with a few years of experience realizes she needs to be ready for the unexpected. But let’s start with expectations and then plan for the unexpected.

Heat and moisture fluctuate, but there is one environmental factor that is dependable – the amount of daylight. The vegetables we grow still need sunlight – 6 to 8 hours of direct sun per day – even as the length of daylight diminishes through the fall. As fall progresses to winter, the daylength shortens, and the sun gets lower in the sky, casting longer shadows.

Will part of your garden be in the shade by mid-October? You should plant your fall crops in the sunniest part of the garden to take advantage of as much sunlight as possible. Also, if you know your garden has warm spots or frost-prone areas, use these to your advantage.

Some cool season plants are quite tolerant of cool frosty nights and, short of a long hard freeze, they can keep going until Thanksgiving, or longer. What kind of plants like fall conditions best? Pretty much the same ones that do well in spring.

If you are starting now, you want plants with a tolerance to frost and a shorter maturing time. For our area in Hardiness Zone 7a, the average first frost is likely to occur between October 17 and October 31. Most of these plants are also better tasting after they’ve been frost-nipped. They survive frost – some even freezes – by turning part of their stored starch into sugars which act as anti-freeze.

Which plants are these? Many of the roots – carrots, beets, rutabagas, turnips, parsnips – can spend all winter in the ground with a thick covering of mulch. Of course, this makes a comfortable home for small rodents who are making your garden their home. (Sweet potatoes taste better when frost-nipped but the aboveground vegetations dies at 32oF.)

There are several above ground vegetables that handle the cold well, too. Most brassicas handle temperatures to at least 28oF and some can tolerate even colder – Brussel sprouts, cabbage, broccoli, cauliflower, and kale for example. Veggies that aren’t brassicas? Examples include scallions, spinach, annual fennel, some head lettuces, though outer leaves are affected.

Different varieties of these vegetables have different cold tolerances. For instance, spinach varieties with thicker, crinkly leaves have better tolerances than those with thin, flat leaves. The names of some vegetable varieties can tell you a lot, too. Expect lettuce with a name like Heat Wave to be a summer variety, while a cabbage named January King and a kale named Winterbor are intended for winter growing.

Determining when to plant your chosen vegetables takes a little thought, but it isn’t hard. Seed packets or catalog descriptions usually list the days to maturation. Winterbor Kale matures in 60 days. If you want your kale to be ready by November 1, count back 60 days – that would be September 2. BUT, the days to maturation calculations listed are for spring planting, and daylength in the fall gets shorter, not longer. Add 10 days or so: that’s August 23.

Were you plagued by insects like white cabbage butterflies and harlequin bugs last spring? They might still be around. During my early gardening years, I was surprised to find that those cabbage worms and other pests don’t disappear after the first frost, or even a freeze. The row covers that give your plants some cold protection (down to 28oF) also stops most insects if the plants are covered meticulously, leaving no way for these pests to enter. Also, consider relying on beneficial insects in all seasons. I’ve seen wasps appear to be looking for something on or around my cabbages. After seeing a wasp catch one and carry it away, I know they are hunting for cabbage worms to feed their young.

Another consideration is how the rest of your garden will fare through the winter. If you look at natural landscapes you see the ground isn’t clear and exposed to the weather. Meadows are covered in vegetation all year, and even the forest floor is covered with leaves where there isn’t other vegetation.

Like a meadow or a forest, you want to protect the soil organisms from the freeze-thaw cycles we experience during our winters. The helpful soil creatures depend on good tilth, that clumpy soil structure which provides movement of air, water and nutrients, as well as surfaces on which microorganisms live. Using cover crops or mulch stabilizes the soil temperature and prevents erosion and soil compaction that results form cycles of freezing and thawing.

Now you’ve got this. You know what to expect and how to deal with it. What about the unexpected?

You probably realize that our weather is not moving smoothly from cool to warm back to cool again over the growing season. In fact, the changes are more abrupt – from cold to hot and back – while precipitation is more likely to be harder bursts of rain. Again, mulch is your friend, moderating the abrupt temperature changes at the soil level while protecting plants from hard rain and splashed soil.

Be ready for unforecasted frosts, too. Keep row covers or other plant protection handy. Learn to forecast your local weather 12-14 hours ahead by watching the wind directions and cloud types that accompany the weather we are experiencing. Over time, you’ll be able to anticipate your local weather.

Have a good fall. You deserve it after this last summer.

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