Brussel sprouts have the unfortunate reputation of being a bad tasting vegetable. However, when freshly harvested and properly prepared, they can be good additions to your diet, offering many health benefits. A cultivated variety of the cabbage family that also includes cauliflower, broccoli, and kale, Brussel sprouts are cruciferous vegetables rich in antioxidants. They contain significant amounts in vitamin A and C, and are high in fiber.
Brussel sprouts require a long growing season, reaching maturity 80 – 90 days after transplanting, and 100 -110 after sowing seeds. Due to their long maturity date, they are an intermediate level plant that is more suited for advanced gardeners who have experience and patience growing crops. Below are a few varieties of Brussel sprouts to help you determine which type to plant.
- Green Gems: ½ inch in diameter, these tiny sprouts derive their name from their emerald-colored sprouts, which glow under sunlight. When cut open, they produce a vibrant yellow interior. Their prolific yield and earthly, buttery flavor make them popular for gourmet cooking. This variety is ideal for gardeners who usually do not like Brussel sprouts.
- Dagan: This variety produces firm, medium sprouts that grow straight and won’t tip over, an occurrence known as lodging. It is a reliable, hybrid variety that takes 100 days to mature, and holds well for harvesting. These sprouts have a small attachment site, which makes them easy to snap off and harvest.
- Diablo: This plant produces smooth, medium sized sprouts with a delicious sweet taste. It is a slow maturing variety, taking around 110 days, so it is better to plant it during the fall rather than the spring to avoid early heat, which they are averse to.
- Catskill: Catskill is an heirloom variety developed by Arthur White in 1941. It produces extra-large plants around 2 inches on a 24 inch tall stalk. Despite its size, you do not need to worry about it lodging due to its sturdy, thick stalk. Producing about 10 buds per stalk, it is ideal for those that do not want a large harvest.
Conditions for Growing Brussel Sprouts
When: Brussel sprouts are a cool weather crop that is best planted 6 – 10 weeks before the first frost date. They will sprout when the temperature is between 45 – 80 °F. If you live in zones 9 – 10, plant them from October through December. Gardeners in cooler areas can grow them during late spring or early summer. If they are planted in hot, dry conditions, they can take on a bitter flavor and become inedible.
Where: Brussel sprouts can be grown in raised garden beds or containers. Raised garden beds are recommended for growing cool-weather crops because they allow you to control the soil quality and maintain a consistent temperature during changing seasons and temperature fluctuations. You also don’t have to worry about soil-borne diseases such as clubroot. Brussel sprouts grow best in full sun in a place that receives at least six hours of sunlight.
The ideal soil is loose and well-draining, with a pH of 6.5 – 7. Like all cabbage plants, they require large amounts of nitrogen to grow well, so make sure your soil has the appropriate amount. However, too much nitrogen will produce fewer and smaller plants.
Avoid planting related vegetables in the same spot for three years. In addition, Brussel sprouts should not be planted together with heavy feeders such as tomatoes and other nightshades, as they will compete for nutrients. To ensure adequate nutrients, mix your soil with several inches of compost or other organic matter before planting. If you have planted beans or peas before, you can follow with Brussel sprouts since legumes enrich the soil with nitrogen.
How: If you want transplants, you can plant seedlings indoors in small containers 3 – 4 weeks before you plan to transplant them outside. When plants reach 5 – 7 inches, they are ready to be transplanted. To avoid transplant shock, pick a shady, cloudy day. Space seedlings 4 inches apart in rows or raised beds and ¼ to ½ inch deep. Before translating, water the garden bed and the plants to ensure a cool environment. Thin them to 12 – 24 inches apart when they reach 6 inches tall. Keep in mind that they can grow to be quite large, so make sure to give them ample space. You should mulch your plants to retain moisture and keep the soil temperature cool.
Care: Apply a nitrogen rich product to your plants after you have thinned them. Repeat this process every four weeks, or two times during the growing season. Since Brussel sprouts have shallow roots, they may require staking. Remove unwanted plants by hand to avoid damaging the root system. Regularly water your plants with 1 – 1.5 inches of water per week. Remove any yellow leaves to prevent the chance of infection.
Brussel sprouts require more boron than other plants. Signs of boron deficiency include small plants or hollow stems, which can be confirmed by a soil test. To remedy this, mix 1 tablespoon of Borax with a gallon of water and use it to evenly water your plants.
Like with all cabbage plants, Brussel sprouts are prone to cabbage worms. If you spot those pests, remove them by hand and drop them in a bucket of soapy water. Alternatively, you can cover crops with garden fabric to serve as a barrier. Companion plants such as garlic, marigolds, and mint can help deter pests like cabbage worms.
They are also susceptible to a fungal infection known as club root, which attacks the root structure of the plant, leading to gnarled roots and stunted plant growth. To prevent clubroot, make sure the plants are healthy and disease free before planting, and compress the soil to eliminate air gaps that can lead to disease. It is important to keep the area free of clubroot, as treatment methods are expensive, difficult, and not very effective. If the area is infected, raise the soil pH to 7.2 by adding dolomite lime.
How to Harvest Brussel Sprouts
Most Brussel sprouts can be harvested after 80 days after planting, with the precise time depending on the variety. Snip off the sprouts when they are 1 – 2 inches in diameter by twisting them from the stem, starting from the bottom of the plant. When you are removing the sprouts, make sure to also remove any yellow leaves that appear. You should harvest once the leaves start turning yellow to ensure tenderness and flavor. Store Brussel sprouts in a plastic bag in a refrigerator, where they can last up to a week. Instead of washing immediately after harvesting, wash them when you are ready to prepare. If you have picked them attached to the stem, store them with a wet paper towel to keep the stalk hydrated.
Brussel sprouts are biennial, which means they will grow for two years before requiring replanting. They can survive some frost and snow, with frost being beneficial to their flavor by triggering energy for sugar production. For improved flavor, harvest them after a frost.