Closely related to broccoli and cauliflower, cabbage has dense and leafy heads that can be green, purple/red, or white. It’s a versatile, cold-weather veggie with tons of vitamin C. It’s also got a ton of other nutrients, vitamins, and fibre.
To help ensure your Cabbage thrives, we’ve put together this how-to video and transcript covering topics like:
Glossary of Cabbage terms
Varieties of Cabbage available
Starting your Cabbage seeds
Caring for Cabbage at all stages
Fertilizer and/or Mulching
Transplanting best practices
Companion Plants do’s and don’ts
Common challenges and Their Solutions
Pests, Diseases and what to do about them
Harvesting and storing your Cabbage
Glossary of cabbage terms
Before we get started, let’s learn a little bit about cabbage.
The premature production of a flowering stem (or stems) on a plant before it can be harvested. Bolting is the plant’s natural attempt to produce seeds for reproduction.
Cabbage is extremely sensitive to overexposure and excessive sunlight, so one way to avoid bolting is by waiting longer into the season to plant your seeds.
The rib-like center of certain leaves. Not only do they physically support the leaf, but they also provide it with nutrients and water.
A transparent-roofed enclosure, built low to the ground, that’s used to protect plants from harsh weather like excessive cold or rain.
Basically, a cold frame works as a mini greenhouse to extend your growing season. They can also be used to harden-off your seedlings.
The round, flattened or pointed heads of this crop which are made of leaves that wrap around each other tightly. In the center of the head is a short, thick stem – also known as the core.
Varieties of cabbage
Depending on the color you’d like to grow, you have a few options.
Cheers A variety that takes 75 days to harvest. It has solid round heads and is tolerant to black rot and thrips. Early Jersey Wakefield A variety with pointed heads, it take 63 days to mature. It stands well and resists splitting. King Cole A large, firm variety with extremely uniform heads, King Cole takes 74 days to mature.
Savoy King A dark green, uniform cabbage that matures in 85 days.
Savoy Queen A large variety that’s deep green in color and has good heat tolerance. This one typically takes 88 days to become harvest-ready.
Red Meteor A firm variety good for all seasons, it’s harvest- ready after 75 days. Ruby Ball Slow to burst, this variety resists both cold and heat and matures in 71 days.
For an early harvest, try Primo or Stonehead varieties.
Quick-maturing Golden Acre and Quick Start varieties will yield 3-pound heads.
For Savoy types, try Alcosa (an early variety), or Wirosa, a late variety that overwinters as-is in southern gardens, but needs protection in the North.
Early Jersey Wakefield is an heirloom variety that resists splitting, is slightly pointed, and produces 2-3-pound heads.
Disease-resistant varieties include Blue Vantage and Cheers.
Cabbage can be directly seeded or started indoors to produce transplants.
In order to germinate, cabbage seeds prefer a soil temperature that is between 55-75°C (12 and 24°C).
Cabbage seeds can be planted outdoors 6–8 weeks before the last spring frost date in a cold frame.
Then, they can be transplanted to their final location about 4 weeks before the last frost.
If you’re planting for a fall harvest, your cabbage can be directly seeded 6–8 weeks before the first frost date.
For a fall crop, directly sow your seeds in early July. You’ll want to plant them about a quarter- inch (6 mm) deep while spaced 4-6 inches (10–15 cm) apart in rows.
Those rows should then be spaced about 2-4 feet (0.6 to 1.2 m) apart.
Thin your seedlings to be spaced 18-24 inches (45–60 cm) apart. Keep your soil moist during germination to prevent a crust from forming on the soil surface, since this causes uneven germination.
Although your cabbage seeds will germinate at low soil temperatures, seedlings are sensitive to frost. However, there’s no need to use a heating mat as you might for other seeds.
Normal room temperatures between 60-70°F plus bright overhead light are ideal conditions for the development of your plants.
Start your seeds indoors in early April, or 4-6 weeks before transplanting. Plant them at a depth of a quarter-inch.
Apply fertilizer to your developing seedlings, starting when their first true leaf appears, using a half-strength starter solution once a week.
Then, once there are two true leaves, apply fertilizer twice a week.
Caring for cabbage
In this section, we’ll cover everything you need to know about watering and weeding your cabbage, plus fertilizer and mulching best practices.
We’ll also cover transplanting, companion planting, and your growing structure options.
Keep in mind that typically, cabbage will tolerate below-freezing temperatures late in their growth. They generally take between 60 and 100 days to mature.
SOIL & SUN NEEDS
Cabbage grows best in rich, moist, well-draining soil with a pH of 6.5.
Prepare your soil for planting by adding in some nitrogen. Either bone meal or composted manure will do the trick.
Also, cabbage needs at least six hours of direct sunlight each day.
Cabbage plants needs good soil moisture. The best quality heads are firm, crisp, juicy, sweet, and sometimes peppery, but without any bitterness.
If your plants don’t get consistent rainfall or water, they can develop poor texture and excessive bitterness. Outer leaves might also turn brown and dry up, or the plant can fail to form a head.
Typically, one inch of rainfall each week is enough – but make sure your cabbage plants are watered evenly, since uneven watering can cause their heads to crack.
Cabbage plants have shallow roots, so in order to avoid damaging them, it’s best to pull any weeds out by hand.
Frequent, shallow cultivation will also kill weeds before they become a problem.
Cultivate just deeply enough to cut the weeds off below the surface of the soil, and be extra careful not to damage your plants in the process.
Plant spacing definitely affects your cabbage’s head size. Close spacing (12 inches apart in the row) produces small heads, while large-headed varieties are spaced wider.
Small-headed varieties are fast maturing and can be successively planted throughout the season.
Heads can be left on your plant in the garden for about 2 weeks in the summer, or 3-4 weeks in the fall.
Pull out any weeds by hand, to protect your cabbage’s shallow root system.
FERTILIZING AND/OR MULCHING
Cabbage is a medium feeder, so you can use a starter fertilizer when transplanting, then side- dress three weeks later with a quarter cup of a 10-10-10 fertilizer per 10 feet of row.
Just be sure to avoid fertilizing your cabbage during their head formation, because this can cause excessive leaf growth and splitting.
Use herbicide-free grass clippings, weed-free straw, or other organic material to mulch your plants.
You can do so to a depth of 3-4 inches, which can help conserve soil moisture and prevent weed growth.
TRANSPLANTING BEST PRACTICES
Seedlings started indoors or in a cold frame are ready for transplant once they have 3–4 leaves and the daytime temperature has reached about 10°C (50°F).
Before you do, though, you’ll want to harden-off your seedlings first. Once your plants have five true leaves after about three weeks, reduce their water intake.
Place your plants outside where they can get a couple of hours of sunlight while being protected from the wind. Then, slowly expose them to more sunlight over the next week or two, bringing them indoors if night temperatures drop below 40°F.
Once they’re hardened-off, seedlings should be planted 18-24 inches (45–60 cm) apart in rows that are spaced 2-4 feet (0.6 to 1.2 m) apart.
You can also stagger your planting in 2-week intervals to prolong your harvest.
Water your plants, and use a transplant starter solution that’s high in phosphorus and low in nitrogen and potassium.
GROWING STRUCTURE OPTIONS
They function as miniature greenhouses to extend your growing season.
These can easily be covered with hoops for frost protection and also to extend your season. They allow for improved soil drainage, which is great for crops like cabbage that need well- drained soils. They also allow the soil to dry and warm up faster in the spring, which means you can start gardening earlier.
Sow 2-3 seeds into individual containers, thinning to one plant per cell after germination. Cell trays allow for better root development of your cabbage plants.
COMPANION PLANTS DO’S AND DON’TS
Beetroot, celery, dill, chamomile, onions, mint, potatoes, rosemary, sage, thyme, lavender, beans, peas, coriander, marigolds, and lettuce are all great companions for your cabbage.
Avoid planting strawberries, tomatoes, and garlic near your cabbage.
Common challenges and their solutions
There are a number of issues, pests, and diseases that can potentially harm your cabbage plants. Not to worry – we’ve outlined them below, as well as how to either avoid or fix the problem.
Cabbage will grow at temperatures as low as 45°F and can tolerate high temperatures up to 80°F, but if it gets any warmer, cabbage will bolt. When a plant bolts, it produces a flower stalk and then goes to seed. Once the flower develops, the leaves get tough and bitter, which then ruin the crop.
Cabbage has a growing season of 65-95 days, and its optimal growing temperature is between (60-65°F).
Split cabbage heads typically happen after a heavy rain, especially when there’s been a period of dry weather. When their roots absorb excess moisture after the cabbage head is firm, pressure from that internal growth causes the head to split. The same thing can happen when heads are fertilized late in the season.
Solution: Prune off a few roots when the heads are moderately firm. You can do so by cultivating/weeding close to your plants with a hoe.
Also, keep your soil evenly moist throughout the growing season - cabbage typically needs 1 -1.5 inches of water every week.
Finally, avoid fertilizing your cabbage after their heads begin to firm – by using a slow-release fertilizer, it can help keep soil nutrients even and prevent over-fertilization.
You’ll also want to harvest early varieties as soon as their heads are firm.
Small black beetles that feed on seedlings and jump when disturbed. The damage from their feeding habits can kill your seedlings off entirely.
Solution: Use a lightweight floating row cover at the beginning of the season to prevent them from becoming an issue.
You can also try a homemade spray using 2 cups of rubbing alcohol, 5 cups of water, and 1 tablespoon of liquid soap.
Test out this mixture on a single leaf first, let it sit overnight, then spray the rest of your plant if you don’t notice any side-effects.
Dusting your plants with plain talcum powder can also help, as well as using white sticky traps to capture these pests as they jump.
Seedlings and transplants suffer more damage from root maggots during a wet, cold spring. These maggots feed on the roots and bulbs, creating tunnels. First, your cabbage plants will begin to wilt, then they can become stunted and yellowed, and heavily damaged plants can then die. Unfortunately, once you notice the damage from root maggots, it’s usually too late to treat them. Instead you can try to protect your vegetables by preventing or removing conditions that maggots thrive in.
Solution: Do not use animal manure or green manure in your garden during the springtime, since rotting and decaying organic matter attracts these maggots.
Be sure to remove any affected plants in the fall (including their roots) and destroy them. This will kill any pupae that might be left over.
Row covers are also an effective option to prevent adult flies from getting near your plants to lay their eggs – just make sure to set up the barrier in your garden by the time adult flies are laying eggs (usually early to mid-May).
Keep in mind too that you’ll want to choose a barrier that allows both sunlight and rain to get to your plants. Because of this, floating row covers might not be the best option for large gardens.
Common organic cures for root maggot include spreading diatomaceous earth (a natural powder made from the skeletons of tiny aquatic creatures) around your seedlings, or using natural predators to fend them off.
Pests that curl their bodies around the stem and feed on it, which causes the plant to be cut off just above the soil surface. When their numbers are high, they can cause severe damage to your garden. Cutworms feed at night and hide in plant debris during the day, and they prey more on new transplants or young plants since their stems are more tender.
Solution: Remove any cutworms, then either crush them or drop them into soapy water. Keep a 3-4 foot buffer of dry soil along the edge of your garden to make it unattractive to cutworms.
Also, remove plant residue to help reduce egg-laying sites, and get rid of weeds which can host young cutworm larvae. Be sure to till your garden before planting, which helps to expose and kill any larvae that might be present.
Use compost instead of green manure, since manure might encourage egg- laying.
Also, try placing aluminum foil or cardboard collars around your transplants to create a barrier which will stop cutworm larvae from feeding. Simply place the collars around your plants so that one end is pushed a few inches into the soil, and the other end is several inches above ground.
Imported cabbageworm, cabbage loopers, and diamondback moths are the most common caterpillars that are a problem for your cabbage patch. All three of them feed on leaves, with the older, larger caterpillars causing the most damage.
Solution: Treat caterpillars when they are still small and before they cause too much feeding damage by hand-picking them and then dropping them into a pail of soapy water to kill them.
Also, destroy crop residue immediately to prevent hiding spots for caterpillars over the winter. Make sure to remove any weeds (especially wild mustard, peppergrass and shepherd’s purse) since they can all serve as hosts for these pests.
Floating row covers made of lightweight all-purpose garden fabric can also help keep the adult moths from laying eggs on your plants.
Fit the row covers either directly over your plants, or over metal hoops/wooden frame to cover your young plants.
Then, you can remove the row covers after you harvest.
There are also a few sprays, oils, and bacteria that can be effective - like Neem oil and Spinosad.
Finally, predators like paper wasps and parasitic flies and wasps are natural enemies of these caterpillars. They don’t sting or bite, occur naturally in gardens, and help reduce caterpillar numbers.
These pests leave large holes in the leaves, or they eat them entirely. They leave behind a slime trail, feed at night, and thrive in damp weather.
Solution: If possible, hand-pick any slugs at night when they’re most active. You can also try attracting them to traps either using cornmeal or beer.
For a beer trap, dig a hole in the ground and place a large cup or bowl into the hole. It’s best to use something with steep sides so that the slugs can’t crawl back out when they’re done.
Fill the bowl about three quarters of the way full with beer, and let it sit overnight.
In the morning, the bowl should then be full of drowned slugs that can be dumped out for the birds to eat.
For a cornmeal trap, put 1-2 tablespoons of cornmeal in a jar then lay the jar on its side near your plants. Slugs are attracted to the scent, but they can’t digest cornmeal so it eventually kills them.
You can also try placing a barrier around your plants of diatomaceous earth (a natural powder made up of the skeletons of tiny aquatic creatures) or even coffee grounds, since they can’t crawl over these.
Large numbers of these pests can stunt the growth of your plants, or even kill them. They’re small, grey-green in color and covered with a white waxy coating. They prefer to feed deep down in the cabbage head and might be hidden by the leaves.
Solution: If aphid numbers are limited to just a few leaves or shoots, then the infestation can be pruned out to control them.
Be sure to check your transplants for aphids before planting, and use tolerant varieties when possible. Reflective mulches like silver plastic can also help deter aphids from feeding on your plants.
Any sturdy plants can be sprayed with a strong jet of water to knock aphids off, while insecticides are only needed if the infestation is very high (in general, plants can tolerate low to medium level infestations).
Insecticidal soaps or oils like neem or canola oil are usually the best method of control – just be sure to check their labels for instructions.
If there’s a lot of them on your plants, the leaves might become distorted. Typically, leaves are covered in a rough speckled patten and might also appear silvery.
Solution: Avoid planting your cabbage next to onions, garlic or cereals where very large numbers of thrips can build up.
You can also use reflective mulches early in the growing season to deter them.
Safe insecticidal soaps made from naturally occurring plant oils and fats (like Spinosad or neem oil) are also effective for knocking down heavy infestations, and they won’t harm most of the helpful insects either.
Also, you can release natural predators like minute pirate bugs, ladybugs, and lacewings to manage your thrip infestation.
For best results, make these releases after knocking down severe infestations first – preferably with a strong spray from your garden hose.
General (important) notes before we get into individual garden diseases:
When you find diseased plants in your garden, collect the leaves, stems and tops, then either burn or dispose of them.
Do not put diseased plants into your compost pile.
Avoid things like crowding, overwatering, planting in poorly drained soil, or inadequate insect control.
These factors all support the growth of diseases.
Irregularly-shaped dull yellow areas will appear on the leaf veins, which then expand to the leaf midrib – creating a characteristic “V-shaped” lesion. These lesions might come together and give your plants a scorched appearance.
Solution: Plant disease-free seeds or resistant varieties when possible – but before you do, soak them in 122°F water for about 25 minutes to kill any lingering bacteria.
Keep in mind that soaking your seeds this way isn’t 100% effective against black rot, and might actually lower your seeds’ germination rate.
Also, practice a 2-year crop rotation, and only use clean, sanitized tools near your cabbage plants.
Wash your tools with a diluted bleach mixture - about 1 part bleach to 10 parts water – then rinse with cool water and towel dry after each use.
This disease causes the damping-off of seedlings. Round or irregularly-shaped gray spots will appear on leaves with dark edges. These lesions might be covered in pink masses during certain weather conditions.
Solution: Use disease-free seeds, or treat your seeds with hot water to remove the fungus before planting.
Also, remove and destroy crop debris after you harvest, or plow it deeply into your soil.
Small yellow areas and irregular brown lesions will appear on the upper leaf surface, while gray mold grows on the lower leaf surface.
Solution: Plant resistant varieties when possible, prune or stake your plants, and remove any weeds to improve air circulation.
Water your plants early in the morning or use a soaker hose, which gives your plants time to dry out during the day.
Keep the ground under any infected plants clean during the fall and winter to prevent the disease from spreading.
Be sure to remove and destroy any plants with a serious infection. Keep in mind that downy mildew is much easier to control when a plant’s leaves and fruit are kept protected by a copper spray.
You can begin treatments two weeks before the disease normally appears, or when you’re in for a long period of wet weather.
You can also begin treatments when the disease first appears, then repeat at 7-10 day intervals for as long as you need to.
BACTERIAL SOFT ROT
Water-soaked lesions will appear on the cabbage head, which then grow to form a large rotted mass of cream colored tissue which is liquid underneath (gross.). The surface of these lesions usually cracks and oozes slimy liquid which turns tan, dark brown or black when exposed to the air.
Solution: Rotate your crops and plant your cabbage in well-draining soils or raised beds. Only harvest cabbage heads when they’re dry, and avoid damaging them in the process.
Small white patches will appear on the upper and lower leaf surfaces, which might also show some purple blotching. Patches often come together to form a dense powdery layer, coating the leaves and causing them to eventually drop from your plant.
Solution: Plant disease-resistant varieties when possible, and then provide good air circulation by not crowding your plants.
Potassium bicarbonate (which is similar to baking soda) can actually eliminate powdery mildew once it’s there, and does the job fairly quickly.
This disease can also be controlled by applying sulfur sprays, dusts, or vapors.
SCLEROTINIA ROT (WHITE MOLD)
Irregular gray lesions will form on the leaves while white-gray lesions appear on the stems.
As soon as you notice any diseased plants, destroy them immediately.
If your soil is infected, remove as much of it as you can and then replace it with clean soil. You can also use a barrier, like plastic or mulch, to cover the infected ground and prevent the spread of the disease.
If possible, remove all crop residue after harvesting.
This disease can survive and develop if residue is left behind – and since white mold spores are long-lasting, you don’t want to give them a chance to survive the winter.
Harvesting and storing
Harvest your cabbages when their heads reach a usable size, simply by cutting the head off above the outer leaves.
Keep in mind that once cabbage heads reach their mature size, there’s a risk that they will split before they’re harvested.
Heavy rain is typically a cause of these split heads, and you can minimize this risk by twisting the head a quarter turn, or by shearing one side of the roots with a spade.
This will reduce water flow into the head, which helps prevent splitting.
Also, some varieties are actually less likely to split, so you can plant those ones when possible.
Cabbages can last for months, but only in cold and moist conditions. Ideally, you’ll want to store them in temperatures between 32-40°F with 95% humidity.
This is colder and more moist than a fridge, which can be difficult to achieve for most home gardeners. If you want to store your cabbage more long-term, you’ll likely need a root cellar.
A time-honored way of preserving your cabbage is by the process of fermentation. The European version is sauerkraut, while traditional Asian fermented cabbage is called kimchi.