Cooking Greens to Harvest in Central Virginia in April
Out with the old! In with the new!
Outdoors, collards, kale and spinach that have over-wintered will be coming to an end. Most years, the collards and then the kale bolt in mid-late March, and the overwintered spinach in April.
Fast growing crops like mustard greens and senposai from spring transplanting will be ready to harvest as leaves from early April; collards and kale from mid-April. Beet greens might be ready at the end of April, or it might be May before we get those, depending on the weather and our sowing dates.
From the hoophouse, we are getting the last of most of our indoor greens. The Russian kale, the chard and the Frills (frilly mustards) are bolting. We do have spinach we sowed in January, which will continue all this month. The Bulls Blood beet leaves no longer look very appetizing, but we could cook those up early in the month. The milder winter means earlier bolting this year.
Cooking Greens to Sow in Central Virginia in April
Chard is our best summer cooking green. Chard (Beta vulgaris var. cicla) is the same species as beetroot and, like beets, is a biennial. Hence it will not flower until the second year after planting, and can provide fresh greens all summer and fall, until halted by hard frosts. Even then, the root may survive and regrow the next spring. Leaf beet, also known as perpetual spinach, is a chard, with thinner stems and smaller leaves than most Swiss chard. It is the closest in flavor to spinach for growing in hot weather
If you prefer spinach in spring, as we do, grow that first, and switch to chard for summer, sowing in plug flats or soil blocks three weeks before your last frost date. (We sow March 24-April 6)
If you want chard in spring, you can start flats earlier or direct seed outdoors two or three weeks before the last frost date.
We also use beet greens for cooking, although our main purpose is to grow beets. Our last date for sowing beets in spring is 4/15.
There are other hot weather greens you could sow in central Virginia and warmer climates.
In the hoophouse, it is definitely too late to plant cooking greens. Anyway, we are filling the tunnel with early tomatoes, squash, cucumbers, and peppers.
Cooking Greens to Transplant in Central Virginia in April
Outdoors, we transplant our main cabbage and two sowings of broccoli under nets or rowcover within 6 weeks of sowing. Rowcover is our usual choice, because changeable weather and late frosts are more of an issue here in spring than bugs are. It is important to protect young cabbage and broccoli with 5-8 true leaves from cold stress (<40°F/4.5°C for a few days, or longer at 50°F/10°C). At this stage they are particularly sensitive to cold, which can cause early bolting (and very low yields). After a few weeks, when the weather is more settled, we move the rowcover to newer, more tender crops.
Mid-April: We use saved extra transplants to fill gaps in the broccoli and cabbage plot, at the same time planting out alyssum every 6’ (1.8 m) in the center of the beds. These little flowers attract beneficial insects (see more below).
Late in April we will transplant leaf beet and chard – it doesn’t take long for the seedlings to grow. Often we cover the prepared bed with hay mulch, then make two rows of “nests” in the 4’ (1.2 m) wide beds. We don’t space the rows evenly across the bed, but bunch them in close to each other in the middle. This saves the paths for us to walk down.
In the hoophouse, in very early April we use young spinach transplants to fill gaps only in the outer thirds of the beds, leaving the bed centers free for the tomatoes, etc. It would be better to have done this in late February and March, but this year we didn’t get to it. We won’t get high yields, planting this late.
Other Cooking Greens Tasks in Central Virginia in April
Early April: We move rowcover from turnips, senposai, early cabbage, kohlrabi and onions as needed for the broccoli and the maincrop cabbage.
Mid-April: We move rowcover from spring-planted kale, collards, mustard and early lettuce for the tender crops. We finish filling gaps in the broccoli and cabbage plot, at the same time planting out alyssum (sown March 3) one plug every 6’ (1.8 m) in the center of the beds. See the Special Topic for April below, for more on farmscaping, as this method of pest management is called.
Late April: We move rowcovers from for the broccoli and the maincrop cabbage. With broccoli, the first weeks after transplanting are vegetative growth, adding leaves until there are about 20, when “cupping” starts — the leaves start to curl up, forming a convex shape rather than growing straight out. The cupping stage is usually10-14 days before harvest starts, depending on temperature. If the weather gets too hot — more than 80°F (27°C) — too soon, the broccoli may grow only leaves, and not head up.
In the greenhouse, we start to have less work, which is fortunate as outdoor work increases.
Special Cooking Greens Topics for April: Farmscaping for Brassicas
Farmscaping is the inclusion of specific flowers to attract beneficial insects. The pollen and nectar offer an alternative food source to beneficial insects when their insect prey is scarce. And if their insect prey is right by the flowers, what could be better?
We plant Sweet Alyssum in our spring broccoli patch to attract predators of aphids and caterpillars; Putting 5 percent of the crop area in plants that attract beneficial insects can seriously reduce pest numbers. Sweet alyssum, yarrow, dill, coriander (cilantro), buckwheat, mung beans, other peas and beans, black oil-seed sunflower, calendula and cleome all work well to attract a range of insects (especially ladybugs and lacewings) that eat or parasitize aphids. Pans of water and gravel will help attract aphid midges and lacewings. The gravel provides surfaces for the insects to land on while drinking. Farmscaping can make other insect control unnecessary in a good year. Beneficials will generally move up to 250 feet (75 m) into adjacent crops.
We also plant “insectaries” around the garden, usually at the ends of beds with crops that will be growing for several months. These flowers are planted inside rings sawn from a plastic bucket. The rings alert the crew that something special is there, not just a clump of weeds. Mix flowers to have something blooming all the time.
Another method for incorporating farmscaping is to plant beneficial-attracting perennial flowers in areas that are too challenging to use for production: edges, slopes, tight corners, hedgerows, and field borders.
Other Pest Management for Brassicas
Using rowcovers keeps many pests off the plants while they are small. We have not had much trouble with aphids, perhaps partly because our overhead sprinklers wash them off and they can’t travel far. Insecticidal soap sprayed three times, once every five days, can usually deal with aphids. Our worst pest is the harlequin bug. For lack of a better organic solution, we handpick them. Ladybugs are reputed to eat harlequin bug eggs.
Sometimes we have had enough cabbage worms to make Bt (Bacillus thuringiensis) necessary, but usually paper wasps eat the caterpillars. The action level threshold is an average of 1 cabbage looper, 1.5 imported cabbageworms, 3.3 armyworms or 5 diamondback moth larvae per 10 plants. Below this level you can do watchful waiting rather than spraying with Bt or spinosad. We are lucky enough to have the naturally occurring wasp parasite of cabbage worms, the Braconid wasp Cotesia species, which are found as small cottony white or yellowish oval cocoons in groups on brassica leaves. The Cotesia wasps like umbelliferous flowers, and overwinter on yarrow as well as brassicas. If you find Cotesia cocoons in the fall and your brassicas aren’t diseased, you can leave plants in the field over winter. Or you could collect up leaves with cocoons in late fall and store them at 32°F–34°F (0°C–1°C) until spring. Hopefully no one will clean out your fridge without checking.
Richard McDonald has good information in his Introduction to Organic Brassica Production. He reports that broccoli plants with six to sixteen leaves (just before cupping) can lose up to 50 percent of their leaf area without reducing yield. Moderate defoliation (20–30 percent) causes the plant to exude chemicals that attract parasitic wasps and predatory insects. If you relax and allow this amount of defoliation early on, you can encourage these beneficial insects to move in and begin foraging in the area. Once the plants cup, you want to prevent further defoliation by having the most beneficials and the fewest pests on site. If pest levels are above the action threshold, cupping is the stage to take action, and probably not earlier.
To float out worms and aphids after harvest (before cooking!), use warm water with a little vinegar and soak for up to fifteen minutes, then rinse.