There are many varieties of cabbage. How you plan on eating this vegetable will determine the varieties that you’ll plant. There is your standard green cabbage that is used in slaws and cabbage rolls, red cabbage that is interchangeable with green cabbage, savoy cabbage which is delicious in salads or quickly stir-fried, and Chinese or Napa cabbage that has a mild peppery flavor that’s delicious in salads. These are but a few of the varieties available to the home gardener.
Cabbage belongs to the Brassica family and is related to broccoli, cauliflower, Brussels sprouts, and kale.
As with other brassicas, the pH of the soil should ideally range from 6.2 to 7.0. This range will discourage clubroot disease. Amend your soil with two inches of compost worked into the dirt. Cabbage prefers very fertile well-drained loamy soils. If your soil is very sandy or composed of a lot of clay, add organic matter to it. Because of cabbage’s nutrient needs, nitrogen-rich amendments such as blood meal, cottonseed meal, or composted manure are excellent soil supplements.
When to Plant
You’ll want to start cabbage seeds indoors 6 to 8 weeks before the last spring frost and before the first fall frost. Harden your seedlings off over the course of a week and then transplant outdoors 2 to 3 weeks before the last spring frost and 2 to 3 weeks before the first fall frost. Remember, the cooler the temperatures, the better (and sweeter!) your cabbage will taste. In warmer climates, plant cabbage to mature before temperatures reach 90 degrees F.
In zone 8 and warmer areas, it’s recommended that you plant in late winter for a spring harvest and in late summer for a fall harvest.
Your seedlings can tolerate temperatures of 40 to 50 degree F without a problem. However, if your plant is young, with a stem diameter at least as thick as a pencil, and is exposed to lower temperatures, it may send up a seed stalk prematurely without forming a head of cabbage at all. Cover with row covers if there’s a chance of temperatures dipping into the 30s.
How to Plant
Cabbage needs space to grow, so set transplants about 12 to 24 inches apart, depending on the variety and how large they’ll grow. Set the plants in deeply, with about half the main stem buried.
You can direct seed cabbage into the garden if you want to, although transplants work better. Plant your seed 1/4 to 1/2 deep, 12 to 18 inches apart. Keep the area moist and thin to desired spacing once they being to grow.
To produce good heads, your cabbage needs plenty of moisture, and will need even more when the plant is actively forming those heads, as well as when temperatures climb above 80 degrees F. If you find that you’ve allowed the soil around your cabbage to become dry, apply two to three cups of water at the base of each plant. Don’t over water to compensate—you’ll cause the heads to split.
To keep moisture in the soil, much with compost, about 2 inches thick. Don’t allow the mulch to touch the heads, however, as it may encourage rot.
Competition with weeds and other brassicas will slow the development of your cabbages, so keep weed growth down and plant cabbage away from others in the same family. You can apply an organic fertilizer such as Protogrow® to the soil as the plants are developing new leaves and when they start forming heads.
Do not plant your cabbage in the same spot year after year as it will encourage the proliferation of the diseases and soil pests most attracted to the plant. Move them to a different spot in the garden each season. Avoid planting next to vegetables in the nightshade family (tomatoes, peppers) as it will stunt growth. Avoid planting radishes and mustards next to your cabbages as well, as these plants attract harlequin bugs, which cause wilting and distorted brown leaves on the plant.
Your cabbage is ready for harvest when the head is firm to a gentle squeeze. Your cabbage can look ready, but still be flimsy and loose-leafed on the inside, so don’t rely on sight alone. Cut the stem right below the head. It’s best to harvest first thing in the morning because the sugar content is at its highest, which will make for the best flavor.
If you find your cabbage maturing all at once, spread the harvest out by breaking up a portion of the roots on some of your cabbage to reduce water uptake. Using both hands, twist the cabbage head about a quarter of a turn or plunge a shovel into the dirt at one side of the head. This will also reduce the chance of split heads.
If a head does split, harvest it right away. Remove cut stumps from the garden so that diseases and pests will not become persistent.
Late season cabbages store well in the coolest part of a root cellar.
Some of the possible pests that can be harmful to your plants are caterpillars, which include cabbage worms, cabbage loopers, cutworms, army worms, diamondback moth caterpillar, and flea beetles. Apply a Bt solution to the plant every 7 to 10 days, and of course, hand pick off those that you see.
Cabbage root maggots are the larvae of flies and are the size of a grain of rice which feed on the roots. To keep them from hatching, firm the soil well around each seedling. Put tar paper or foam rubber below each plant, resting firmly on the soil to keep the flies from laying their eggs.
Harlequin bugs are a shield-shaped insect that is usually black with bright red, yellow, or orange markings. Remove these insects by hand daily, as well as removing their egg clusters from the plants. Avoid planting cabbages next to radishes and mustards, which attract harlequin bugs.
The clubroot fungus causes wilted, discolored leaves and the roots are a gnarly mess. Most clubroot fungus is brought in from purchased transplants, so growing your own seedlings should help avoid this. If you find plants with the fungus, pull them out and destroy them. There’s nothing that can be done or any corrective measures taken to save the plant. Avoid planting any brassicas in the affected section of the garden for at least 4 years. Clubroot prefers acidic conditions, so adding lime to acidic soil at least two months before planting can help prevent the fungus.
Fusarium wilt will cause the lower leaves to turn brown. Your plants may deliver a harvest, but it’s recommended that affected plants be destroyed.
Moldy heads can be caused by fungal white rot or downy mildew. Destroy any affected plants. Insure your plants have adequate spacing with plenty of air circulation. Avoid watering your plants in the evening and don’t soak the plant itself. Instead, water around the perimeter of each plant.