BRUSSELS SPROUTS FACTS
Growing Brussels Sprouts originated in the area around Belgium in the 13th century. Brussels is a major Belgian city that they were named after.
Growing Organic Brussels Sprouts are in the same family as cabbage; they even look like miniature cabbages.
Growing Brussels Sprouts for nutrition is a good plan as they contain lots of Vitamins A and C, folic acid, and dietary fiber.
WHEN TO PLANT BRUSSELS SPROUTS
Various varieties of Brussels Sprouts take anywhere from 80 to 130 days to harvest, depending on the weather.
Brussels sprouts prefer cooler weather, growing best in coastal areas of the Pacific Coast regions and in more northern climate zones such as New York State or the Province of Ontario, Canada.
In warmer climate areas, Brussels sprouts are planted mid-summer for a fall harvest as they prefer to be harvested in cooler fall weather.
Heat resistant varieties have been developed that can be harvested in the summer, but most varieties will become bitter in the summer heat, so it’s better to plant them about 90 to 100 days before the average frost in your area.
In the fall, when harvesting, allow Brussels sprouts to go through a couple of frosts; the cold temps bring out the sweet flavor, somewhat like apples.
If you live in the deep south, you can plant in the winter time for an early spring harvest.
WHERE TO PLANT BRUSSELS SPROUTS
Brussels sprouts require full sun, at least 8 hours daily, with minimal shade.
Successful planting of Brussels sprouts is greater in cooler climate areas.
Plant Brussels sprouts in areas where there have been no family members for at least 2 or 3 years. Family members include cabbage, broccoli, kale, kohlrabi, and cauliflower, to name a few.
Brussels sprouts prefer well-draining soil that is rich in organic matter and high in nitrogen which can be provided using generous amounts of compost and/or composted manure.
PREPARING THE SOIL
Brussels sprouts grow best in soils with a pH level around 6.0 to 7.5, preferably toward the higher end of that range.
Avoiding club root in Brussels sprouts is more successful if the pH levels are above 6.5. Applying lime will bring your pH level up if needed.
Upon marking out your rows, spread a couple of inches of compost or composted manure in the rows and rototill or spade it under. This should give your sprouts any needed nutrients.
CHOOSING THE RIGHT VARIETIES FOR YOUR AREA
Check with your county extension office to see if there are any diseases or other challenges to growing Brussels sprouts in your area.
Powdery Mildew, Light Leaf Spot, and Rust are common diseases in Brussels sprouts, so check to see if there are problems with these diseases in your region.
Make sure the varieties you choose have enough time to harvest after frost in the fall.
SEEDS AND GERMINATION
Once you’ve initially purchased Brussels sprout seeds, they should remain usable for up to 4 year if you store them in a cool, dry place.
Brussels sprouts will germinate at soil temperatures of 40° to 86°F, but prefers the higher temperatures to germinate.
At 75°F, Brussels sprout seeds will germinate in 6 to 8 days typically.
Because the optimal time to plant Brussels sprouts is late spring to mid-summer, starting them indoors is unnecessary so we aren’t going to address that in this article although it can be done.
PLANTING SEEDS DIRECTLY INTO YOUR GARDEN
If your typical frost is around the first of October, depending on the variety of Brussels sprouts selected, you’d want to plant around the first of June to the first of July.
If you’re planting seeds directly to your garden, which is what we recommend, plant seeds every 3 to 4 inches in rows 30 to 36 inches apart.
Plant the seeds in the rows at a depth of about ½ of an inch.
Once the plants have come up and are well established, thin them to about 18 to 24 inches apart in the rows.
SUCCESSFULLY GROWING BRUSSELS SPROUTS UNTIL HARVEST
When you thin Brussels sprouts, you can transplant the thinned plants to new rows if desired.
If your area is windy, stake your plants to keep them upright.
As the sprouts mature, some leaves will turn yellow; remove these leaves to help the sprouts develop. You can also remove the lower plant leaves to help strengthen the rest of the plant.
2 or 3 weeks before your anticipated harvest you can remove the top of the plant as well – the sprouts should have about a ¾ inch diameter.
You may want to side-dress your plants with composted manure about halfway through the season if the plants look like they could use a boost.
This past gardening season we tested a liquid organic leaf spray fertilizer called Organic Garden Miracle™. We sprayed most of our garden plants with OGM™. The sprayed veggies were more robust than the unsprayed plants, and the flavor was superior as well – sweeter and juicier. You may want to give OGM™ a try. We’re pretty impressed.
MULCHING & WEEDING
If air temps rise over 80°F, mulching with 3 to 4 inches of grass clippings or barley straw will help both to keep the soil temperature cool, but also will help control weeds.
Because the roots of growing Brussels sprouts are close to the surface of the soil, it’s important to weed carefully – or mulch. I prefer mulching as I am not much of a fan of weeding.
If weeds come up close to the plant, pull them carefully or cut them off – avoid damaging the plants.
WATERING BRUSSELS SPROUTS
Brussels sprouts require about an inch of water weekly, sometimes 2 if it’s very hot and dry. If you’ve mulched, though, you won’t likely need to water more than an inch even when it’s hot as the mulch will keep the moisture from evaporating.
Drip irrigation is almost always superior to overhead watering, but if you just can’t afford to use drip irrigation, water in the morning so the plants can dry out by noon or so.
When you do water, water enough to soak the soil at least 6 inches into the ground as light watering has very little value to the sprouts.
Too much fluctuation in soil moisture will result in the sprouts splitting or becoming bitter.
COMPANION PLANTING AND ROTATION CONSIDERATIONS
Brussels sprouts grow well with chamomile and garlic, both of which are said to improve the flavor of sprouts.
Catnip, hyssop, rosemary, and sage all repel cabbage moths from your sprouts.
Dill is said to improve the growth of your sprouts and their overall health.
Nasturtiums deter various bugs, beetles, and aphids from Brussels sprouts.
Beets add minerals to the soil and your compost as well.
Celery is a repellant to the white cabbage butterflies.
Onions discourage aphids, weevils, rust flies, carrot flies, fruit tree borers, and moles.
Potatoes also discourage cabbage worms.
Growing Brussel spouts with spinach works well as spinach matures quickly and sprouts slowly, so the spinach will be out of the way when the sprouts need to mature.
Brussels sprouts shouldn’t be planted near strawberries as mildews from strawberries may affect sprouts.
As mentioned previously, don’t follow cabbage family members with other family members but once every 3 years.
WHEN TO HARVEST BRUSSELS SPROUTS
Brussels sprouts are the best between 1 and 1.5 inches in diameter, but are good up to 2 inches in diameter.
It is best to wait until after a good frost in the fall to harvest; a frost brings out the flavor in the sprouts.
The sprouts will mature from the bottom up, producing many sprouts per plant.
Give each sprout a sharp twist to remove from the plant. Or, pull the entire plant up and move it to a cool, dark, and dry storage area and pluck the sprouts as needed.
STORING BRUSSELS SPROUTS
Brussels sprouts will store decently in the fridge for about a week, or if you can store them at 32°F, they’ll store for 3 to 5 weeks.
As mentioned in the previous section, you can store them in a root cellar or similar by pulling up the plants and leaving the sprouts intact on the plants.
You can also blanch Brussels sprouts and freeze them.
PREVENTATIVE AND NATURAL SOLUTIONS TO COMMON PESTS
Flea Beatles are very small beetles – about 1/16th inch to 1/8 inch long – that chew small round holes in leaves. Their color varies from black, brown, blue, and bronze to grayish – and some have stripes.
Flea beetles jump like fleas when startled, hence the name.
If a flea beetle infestation is heavy, they can stunt or kill plants, especially seedlings.
Most garden centers sell sticky yellow traps that will trap flea beetles in the spring time, particularly when your plants are seedlings.
To prevent flea beetles from getting out of control, keep your garden area free of weeds and debris. Early in the season, use row covers to protect your plants up until flowering.
Cabbage worms, cabbage loopers, and diamond moths feed on seedlings of cabbage family crops. The cabbage worm is the most common pest.
The cabbage worm moth is a white butterfly with black spots. The cabbage worms are greenish with yellow stripes and about an inch long.
Cabbage looper moths are dark brown with white squiggles on their wings, and the caterpillars are pale green with white stripes and move somewhat like an inchworm.
The diamondback moths is light brown and when it’s wings are folded show a pattern of 3 diamonds. Their caterpillars are smaller than the previous 2 and are light green.
All three caterpillars feed on cabbage family plants including Brussels sprouts. When the plants are young these caterpillars can be devastating, but they don’t have a lot of effect on older plants.
Hand-picking these caterpillars is effective in most gardens. Dropping them into a bucket of soapy water will drown them.
Dusting your plants with diatomaceous earth (DE) can also eradicate these pests, but the powder must be dry to work.
Row covers will work if you get them over your plants early enough, and if you do, the moths may leave your garden to find easier targets.
Cabbage maggots attack the roots of cabbage family plants. They overwinter in the soil and emerge in the spring as dark gray flies and resemble a house fly.
Floating row covers are probably the best defense against the cabbage fly. If you can keep them out you can save your crop, because once the maggots attack, there’s not much you can do to save your plants.
Aphids are another pest that attack cabbage family plants such as Brussels sprouts.
They are a tiny green or black (usually) insect that feeds on the undersides of leaves, causing them to become curled and dry.
You can use insecticidal soaps or high pressure water sprays on them to knock them off your plants.
DE has also been notable in ridding gardens of aphids.
Cutworms are small worms, about 1.5 inches in length, that chew plants off at about soil level.
Controlling weeds helps to control cutworms, and DE is also effective in controlling cutworms if sprinkled around the base of your plants.
Tip Burn is exhibited by a breakdown of leaf tissue near the center of the Brussels sprout head; it becomes brownish to black and dry.
Tip burn is caused by calcium deficiency which typically happens during drought cycles.
Steady irrigation and mulching can prevent this issue.
Black Rot is a bacterial disease that can seriously affect Brussels sprouts. The bacterium enters the plant’s leaves through pores in the leaves, turning them yellow and the veins black.
Often, the leaves of the plant will drop off the entire plant, and if you cut the infected stem, you’ll see a black ring.
Planting non-infected seeds is the best prevention. Seeds from the Western part of the US are clean, whereas European and Eastern US seeds may be contaminated.
You can also purchase seeds that have been “hot water treated.”
Rotating crops is also effective. Don’t plant cabbage family member crops where others have been within the past three years.
Damping off, or seed rot, is caused by a soil-borne fungus that causes seedlings to shoot up rapidly and then die.
Don’t overwater your seeds or seedlings, and if possible, don’t use overhead irrigation.
Remove diseased plants from your garden and dispose of.
Black Leg is a fungal disease that affects the stem and leaves of cabbage family plants.
At first you’ll see a round canker depression that starts at the base of the stem, becomes larger, and eventually encircles the entire stem. Yellow spots that have gray centers show up on the leaves. These then turn black.
If the infection is severe, the plant will simply topple over.
To prevent this disease, plant non-infected seeds (Western seeds), purchase hot water treated seeds, keep your plant beds clean, don’t over-water, rotate your crops, or plant resistant varieties.
Club Roots is another fungal disease that causes the roots of your Brussels sprouts to enlarge and distort.
The leaves of infected plants will yellow and die.
Make sure your soil’s pH level is above 7.2 or higher, and rotate your crops to new areas.
Always plant your sprouts in well-drained soil, and add lime if necessary to raise the pH level.
Alternaria is another fungal disease that causes small dark spots on the plant stems of cabbage family plants. The small dark spots can rapidly become large dark spots, and the plant will collapse.
Planting resistant varieties is advised, as is planting hot water treated seeds. Avoid overwatering and plant in well-drained soils.
If you spot a fungus, get rid of the infected plant and rotate your plants to a new area next season.
Downy Mildew is a common fungus that attacks garden vegetables when conditions are wet. It appears as a white fluffy growth on the underside of leaves, and later turns to a tannish color.
Planting resistant varieties is advisable, and you can spray this fungus with a homemade fungicide. You can make this organic fungicide spray using bicarbonate of soda (baking soda). In a gallon of water add a couple drops of organic olive oil, a couple drops of environmentally-friendly liquid soap, and 3 tablespoons of baking soda. Spray it on your Brussels sprout leaves to effectively control fungal diseases.