While likely cultivated since the time of ancient Rome, these little sprouts were popularized in Belgium around the year 1500, giving them the name “Brussels sprout.” It’s also no coincidence that the buds from this plant look like teeny little cabbages: as a member of the brassica family, the two are close relatives. Considered by many children and adults to be one of the… less palatable vegetables, we think Brussels sprouts haven’t been given the love they deserve. Bake or sauté this cool weather crop with olive oil, some garlic, and lemon, and we bet you’ll agree that these little gems should have a place in your kitchen as well as your garden.
Bred in England, Roodnerf is one of the best remaining open-pollinated varieties of Brussels sprout. With better sprout uniformity and quality than many other non-hybrid types, plants will produce an abundance of small to medium little cabbage lookalikes along its stem. They’re also extremely cold-hardy, making this a perfect variety for coastal areas and cooler climates. Expect harvests from 3’+ tall plants to begin in late fall or early winter.
Seed Depth: 1/4″
Space Between Plants: 12–18″
Space Between Rows: 18–36″
Germination Soil Temperature: 50–85°F
Days for Germination: 6–17
Sow Indoors: 6 to 8 weeks before average last frost if you live in an area with mild summers. For a fall crop, 12–14 weeks before average first frost date. If overwintering in mild climates, plant in the fall.
Sow Outdoors: When soil temperature is at least 50°F. For a fall crop, 10–16 weeks before average first frost date.
Vegetative: It is possible to propagate by taking root cuttings, but this is not common practice.
Prefers cool to cold weather, especially during maturation. For this reason, a fall crop will be more successful than a spring crop unless your summers stay under 75°F. Sprouts usually begin to form when nighttime temperatures are less than 60°F. The sweetest sprouts will come from a fall planting with harvest time occurring after the first few light frosts. If you live in an area with mild winters, like USDA Zones 8 or 9, grow Brussels sprouts as a winter crop.
Natural: Full sun to partial shade. Prefers afternoon shade in warm weather.
Artificial: Will grow well under fluorescent or LED lamps. Needs at least 6 hours of light daily; however, more is preferred.
Soil: Prefers well-drained loamy soil with high levels of organic matter, but will tolerate clay or sandy clay soils as well. A pH of between 6.5 and 7.0 will keep plants healthy and nourished.
Soilless: Seeds and container-grown plants will do well in a soilless mix comtaining peat moss, perlite, and/or vermiculite.
Hydroponics: Thrives in a media-based hydroponic system. Additionally, microgreens can be grown using a sprouter or on a soilless growing media like wool felt.
Aeroponics: Thrives in aeroponic systems given enough space.
Water: Requires moderate to high levels of water. Provide more in hot weather. Plants may survive hot and dry conditions, but the sprouts won’t form as well or taste as good.
Nutrients: Requires high levels of nutrients. Amend soil with compost or a balanced organic fertilizer before planting. Side dress with compost or feed with liquid kelp or fish emulsion when sprouts begin to form, repeating every 2 weeks. Brussels sprouts prefer a higher balance of potassium and phosphorus rather than excessive nitrogen. Sufficient boron and calcium levels are also important.
Foliar: Will benefit from a foliar feeding containing potassium and other minerals.
Pruning: Pinch off the top set of leaves on young plants to encourage branching. Remove the leaves below each budding sprout to direct the plant’s energy into the sprouts only. If you want all the sprouts to be ready at the same time, pinch off the top of the main stem when most of them are about half their mature size. Otherwise, sprouts will ripen more gradually from the bottom to the top.
Mulching: Use mulch to keep weeds under control, moderate soil temperature, conserve moisture, and protect plants during cold winters.
Deficiency(s): A boron deficiency will cause hollow stems—amend soil with compost before planting to prevent this issue. To fix an issue that is already occurring, a dilute mixture of borax and water can be sprinkled on the earth around the plants’ stems. A potassium deficiency may cause slowed growth and yellowing of leaves. Fix or prevent this by adding clean wood ash to soil before and/or after planting.
Rotation: A 2- to 4-year rotation away form all plants in the brassica family is recommended to prevent pest and disease issues. Plant after a nitrogen-fixing legume, like peas or beans.
Companions: Grows well with beets, buckwheat, cabbage, carrots, chamomile, dill, hyssop, marigolds, mint, nasturtiums, onions, rosemary, sage, spinach, and thyme. Avoid strawberries.
Harvest: Cut or pick sprouts starting from the bottom of the stalk while they are still small and leaves are tightly wrapped. You can take an entire stalk by cutting it at the base and removing individual sprouts. Time harvests to occur between the first few fall frosts and the soil freezing.
Storage: Sprouts can be kept refrigerated for about one to two weeks in a plastic bag.
Seed Saving: This Brussels sprout variety is suitable for seed saving. To do so, you must allow plants to go to flower, which happens in the second growing season for this biennial plant. In very cold climates, plants may require winter protection to ensure they make it to their second year. A distance of 1/2 mile is required to prevent cross pollination with all other Brassica oleracea plants and ensure purity of the variety. After seed pods dry and turn brown on the plant, pick them and break open to remove seeds.
Preserve: Sprouts can be pickled, lacto-fermented á la kimchi, or blanched and frozen for later use.
Prepare: Cut the buds from the stalk and remove any stems they may have. The outer layer of leaves is usually discarded. You can cook them by boiling, steaming, stir frying, grilling, roasting, or even deep frying in batter. Before cooking, they are sometimes chopped in half or slit with a knife at the base of each sprout to aid heat distribution throughout. Be sure not to overcook: if you do, the sprouts will release a sulfur-containing compound that most people don’t enjoy smelling or tasting.
Nutritional: Provides vitamin(s) A, C, K, potassium, iron, antioxidants, moderate amounts of B vitamins, and even some protein. It is also a good source of dietary fiber.
Medicinal: Like other cabbage family plants, Brussels sprouts are considered a very healthy addition to the diet. Several phytochemical compounds found in the plants are being researched for anti-cancer proprieties as well as other immune system benefits.
Warnings: The vitamin K content in Brussels sprouts may cause problems for people taking anticoagulant medications.
Heat up on a cool winter day with this Oven Roasted Brussels Sprout Soup.