Chilly 2012 Winter Solstice morning, Pilgrim Terrace Community Garden, Santa Barbara CA
Cold season things to know about your veggies!
- Fertilize. Healthy plants can withstand more cold. But. From August on, if you anticipate a cold winter, avoid applying fertilizer with Nitrogen, apply at half your summer rate, until after the last frost, to prevent a flush of tender growth that can be damaged by the cold.
- Cool season crops, such as broccoli, cabbage, peas, and onions, originated in northern areas, and can tolerate frost and light freezes of short durations with little damage, plant cold hardy varieties. But other tender morsels often die literal black deaths from killing freezes. Lettuces, marigolds, your fragrant basil, and peppers are usually the first to go.
- Better taste! Cool-season vegetables, such as carrots, broccoli, cauliflower, and Brussels sprouts, produce their best flavor when they mature during cool weather. They react to cold conditions and frost by producing sugars, making them taste sweet, especially Brussels sprouts and kale, but also parsnips and leeks! Ask the folks at the farmer’s market stands if their farms have gotten a frost yet – farms in the country often get frost long before the cities.
- When there are several days at low temps, cole crops (cabbage, broccoli, and cauliflower) and onion sets, producing a seed stalk, called bolting. At that point, harvest good leaves for greens, give the remaining plant to your compost.
Frost we understand, but what’s a Hard Freeze?! When temperatures drop below 32° Fahrenheit (0° Centigrade) and remain there for several hours, even only 2 hours will do it, typically killing seasonal vegetation. Several hours at 25 to 28 degrees, ice crystals form not only on your plant, but in your plant, damaging the cell walls. The coldest time of day is just before daybreak. Clouds at night can absorb and reflect heat back to the earth. Wind can mix the ascending warm air with the descending cold air. Calm, clear nights pose the greatest danger of frost. WIND: If it is windy, less worry. Cold air must settle to form frost and any wind will usually prevent this. Or, a wind may dry your plants, making them more susceptible to freezing!
Frost or freeze survival….
- Watch your weather forecast religiously! Weather has no mercy.
- Water early in the day. Wet soil insulates and protects roots. The water warms up during the day and releases heat slowly during the night. The upper part of a plant may die, but the roots may be strong enough to push up new growth!
- Move frost tender plants under eaves, a spreading tree, into greenhouses, garage. Key word here is UNDER.
- Haunt yard sales, the thrift shop, for old bed sheets, blankets, tablecloths, curtains, towels, shower curtains, burlap sacks, tarps – many end their lives covering garden plants for frost protection! Use newspaper with clothes pins so it won’t blow around. Plastic can be worse than nothing if it touches the plant. Prop up an unused trellis, get creative! Use those wire tomato cages to support your covers! Lay them down among short plants, stand them around taller plants. At home you can lay out a folding chaise lounge chair, or lawn chairs, and cover them!! Secure the edges with stakes, rocks, bricks, or cover with soil. You can use upside down plant pots only if they are large enough that the plants they will cover don’t touch the pot. Put a rock on top to keep them from blowing over! That’s called a hot-cap! The beauty of floating row covers (see image), also called frost or winter blankets, is they can be left in place during the day! Cover the plants mid- to late-afternoon if possible, before temperatures start to drop.
- Set up windbreaks.
- What you can’t cover, that is not frost hardy, harvest. Root crops such as carrots and radishes should be harvested or mulched heavily before a hard freeze.
- If you didn’t cover, wash your plants off before the sun gets on them. Sometimes that will counteract the freeze burn.
- If you did cover, take the covers off, before the sun hits the beds, so everybody can get their sun quotient for the day! Winter days are short!
- Dry out your covers, keep them handy.
- Damaged leaves appear dark green and water soaked at first, later becoming black. If your plant is totally gone, it’s compost, replace your plant. Except potatoes! They will resprout, give ‘em 10 to 14 days!
- Should you trim the ugly damaged stuff off and give your plant a lot of fertilizer to help it? Whoa, Nelly! That’s a NO! The damaged part is protecting the now undamaged part. If you trim and add a lot of fertilizer, tender new growth will form, and that will be toast if there is another frost or freeze. Wait to trim until no more frost is predicted, feed lightly.
Was that groaning, whining I heard? Stop it. Just go out there and cover your plants, no fooling around, you hear?! You will be glad you did, it’s your plants’ lives you are saving! Besides, reviving is harder than covering, and regrowing takes all that time all over again. Also, many will be well past the window for replanting, so cover, cover, cover! Better to have a yard full of ghosts (sheet covers) and look silly, than lose your plants.
Repeat, Religion! Watch WEATHER reports in case of freezes, heavy winds, rain. Santa Barbara’s average First Frost (fall) date AT THE AIRPORT is December 19, Last Frost (spring) date is (was?) January 22. That can vary from the coastal areas to the foothills, and our climate is changing generally to warmer, so these dates may not be viable guides much longer, if even now….