One of the most instantly recognisable winter vegetables, the Brussels Sprouts plant is packed with flavor and nutrients. A particularly good source of Vitamins C and D, this distinctive vegetable is named after the city of Brussels, where they first found popularity.
Instantly recognisable, the Brussels sprout plant is a staple of the vegetable garden.
A member of the Brassica or Cruciferous vegetable family, Brussels sprouts are pleasingly easy to grow. This makes them an ideal starting point for new or nervous vegetable growers. They are also an integral part of an all year round vegetable garden.
Be warned, these are slow-growing plants. They typically don’t begin to produce any vegetables until they reach their full height. However, your patience will be rewarded with a continuous supply of delicious Brussels sprouts. If you want to learn how to grow Brussels sprouts, this is your complete guide.
Can I Grow Brussels Sprouts in Warm Climates?
A cold weather crop, Brussels often taste their best after being to a couple of light frosts.
Growers in the Pacific Northwest’s “fog belt” often have the most success. However, regardless of where you are, with a little time and effort you will be able to grow this delicious crop
Brussels sprouts dislike the heat. Exposure to too much heat can cause plants to bolt and produce bitter tasting vegetables. As long as you can keep the plants cool, they are easy to grow.
In general Brussels like the temperature to be between 60 and 70 ℉. Regular exposure to temperatures over 75 ℉ can cause the crops to bolt.
Most varieties take around 90 days to mature. If you are in one of the warmest USDA Zones grow quick maturing varieties, sowing the seeds early enough to avoid the heat of summer. You can also sow the seeds as the summer begins to fade, enabling you to enjoy a winter harvest.
Gardeners in cool climates can sow crops in early spring or mid to late summer for a fall ready crop. In milder climates you can sow the seeds throughout the fall for a late winter harvest.
Selecting the right variety enables you to avoid exposing the plants to the damaging heat of summer. Regular watering and mulching around the root system can also help to keep plants cool and prevent bolting.
Different Varieties of Brussels Sprouts
There are a range of different Brussels sprouts available. While the variety on offer may initially seem overwhelming, your choice will be limited to the varieties that are best suited to your growing conditions.
Royal Marvel F1 is a resilient variety that is immune to many common diseases. Easy to grow this is an early season variety that is known for its productivity.
Trafalgar is a modern hybrid variety. It reliably produces medium-sized vegetables.
Diablo AGM is a mid to late season variety. It is noted for its vigorous growth habit and ability to tolerate poor soil.
Jade Cross is another reliable variety. With a compact growth habit, this plant is tolerant of windy positions and is immune to many common problems.
While the green sprouting variety is the most common, if you want to add a little color to your vegetable garden you can also grow purple and red varieties.
Falstaff is a nutty, purple red sprout. Taking around 100 days to mature, this is a slow growing variety. After a hard frost, the red color deepens, unlike some varieties this coloring is retained after cooking.
Red Delicious is another popular late season variety. Producing tightly packed red sprouts, like Falstaff, these retain their color after cooking adding interest to your dinner plate.
Make sure that your chosen variety has enough time to mature in your climate. These plants struggle in warmer temperatures.
You can purchase Brussels sprouts either as young plants or as seeds. Growing from seed is more affordable. It also gives you more plants for your money. However, if you don’t have the time or space to grow from seed, buying young plants is just as good.
Growing Brussels Sprouts from Seed
Depending on the variety and where you are growing, you can begin sowing seeds as early as February.
Start your seeds off undercover in modular seedling trays. Fill the trays with a good potting soil and lightly moisten the soil.
Sow one seed per module to a depth of about 2 cm. Put the tray in a bright position.
Germination takes between one and two weeks.
Following germination allow your seedlings to grow on in the same, light position. Regularly check the soil. If it seems to be drying out gently mist or water the soil. When watering be careful not to disturb the seedlings.
Once the last frost date has passed, harden off your seedlings before transplanting into their final position. Seeds sown later in the year can be planted out about 4 weeks after germination.
Planting Brussels Sprouts
A hardy vegetable, Brussels sprouts do best in positions that receive 5 to 6 hours of light every day. They also prefer a dense or clay soil. However with a little extra care and support they grow just as well in lighter or sandy soils.
Your soil should be either slightly alkaline or neutral. It should also contain lots of nitrogen. If you are unsure of the makeup of your soil, a soil test kit is both affordable and easy to use. The information it provides can help to make growing your own vegetables a lot easier.
Before planting, prepare the soil by working in organic matter such as compost. This helps the soil to retain moisture. Brussels sprouts require lots of moisture to support their vigorous growth habit.
A couple of days before planting apply a general purpose fertilizer to the soil. This enriches the soil and helps your seedlings to establish themselves more quickly.
Dig a small hole in the soil. It should be slightly wider and deeper than the root ball of the seedling. The lowest set of leaves should sit just above soil level when the seedling is placed in the hole.
Place the plant in the hole and firm down the soil. Don’t be afraid of compacting the soil, these plants like the soil to be as firm as possible.
Space your plants out to the distance specified on the packet or label. The distance the plants require varies between varieties, but in general Brussels Sprouts should be spaced about 18-24 inches apart.
After planting water well and apply a layer of mulch around the plants. Make sure that the mulch isn’t touching the seedlings.
Supporting Your Plants
Brussels sprouts have shallow roots and are prone to toppling or falling over. This is particularly common when the plants are laden with vegetables and are top heavy. Providing some support from a trellis or a stake, such as these Garsum Green Bamboo sticks helps to keep the plants upright even on windy days.
Some gardeners don’t bother to stake their crops. If the plants fall over they can continue to produce vegetables as long as the stem remains intact. However toppled plants are rarely as productive as upright stalks.
A free standing plant, those in loose soil may require some support.
How to Care for Brussels Sprouts
With a little regular care your Brussels sprouts will soon grow into large, stocky plants. Depending on the variety, once mature and at their full height, each plant produces about 5 vegetables per week.
Brussels sprouts have shallow roots. These can be easily damaged when weeding. Many people avoid weeding around the plants while they are actively growing to prevent accidental damage. A layer of mulch around the plants can deter wed growth.
When to Water
Brussels sprouts require lots of water. The soil around the plants should always be moist or damp. The Gouven Moisture Meter provides an accurate and easy to use way of monitoring the water content of your soil.
If it hasn’t rained you will need to give 1 to 1.5 inches of water a week. A garden sprinkler can be used to easily keep water thirsty plants hydrated.
In warmer climates growing plants require more frequent watering to keep them cool and hydrated.
Fertilizing your Plants
If planted in rich or fertile soil, there is no need to fertilize your plants.
Plants growing in poorer soils will benefit from a dose of organic, slow release granular fertilizer. This provides enough nutrients to sustain the plant throughout the growing season.
A top dressing of fertilizer which is rich in nitrogen can also be applied once the plant is established. This encourages lots of foliage to emerge. Dried poultry manure pellets are an ideal choice. You can also apply a dose of ammonium sulfate to the base of the plants.
Companion planting is a great way to encourage healthy and bountiful crops. It can also help to prevent disease and attract beneficial insects and pollinators to your garden.
Brussels sprouts do well alongside other Crucificae or Brassica family members such as broccoli, cabbage and cauliflower. However this combination is not without risk. Planting lots of members of the same family close together can encourage disease to spread more quickly.
Good companions include:
These are a great companion plant for many vegetables.
Brussels sprouts struggle when planted close to pole beans, kohlrabi and strawberries.
Common Problems and How to Solve Them
A member of the Cruciferous vegetable family. If you are growing Brussels every year, employing even a basic form of crop rotation will help to keep your plants and soil healthy. In particular it can help to deter common brassica issues such as club root, black rot and blackleg. These are all nasty diseases that can be difficult to cure. Keeping a neutral soil pH and not over watering can also help to prevent these issues.
Club root in particular is a vigorous disease that can stunt growth and cause plants to wilt. Club root also damages the root system, slowly turning it into a mushy, foul smelling mess. Should club root strike you will have to avoid growing brassicas in that patch of soil for up to 9 years.
Cabbage root fly is another common problem. Targeting all members of the Brassica family, placing a brassica collar, such as the Vitax Cabbage Collar, around the stem of the plant keeps the pest away.
Similarly the caterpillars of the cabbage white butterfly can be a particularly destructive pest. Covering your crops with horticultural fleece or netting, such as Agfabric Netting protects them from most infestations.
Although an attractive insect, the caterpillars of the cabbage white butterfly can be incredibly destructive.
Ideally your sprouts will be tightly compacted vegetables. Blown sprouts are those that are open and leafy. This can be caused by planting in loose ground.
Remove blown vegetables as soon as you notice them. While they are edible they will not taste as nice as compacted Brussel sprouts.
F1 hybrid varieties are far less likely to develop this issue.
Harvest and Storage
Brussels sprouts at the bottom of the plant mature before those at the top. Most varieties are ready to harvest when they are roughly the size of a large marble. Don’t allow them to get much larger than this. If left on the plant for too long the vegetables can turn bitter or crack.
Upon reaching its full height, the plant will begin to produce vegetables.
Brussels sprouts form in the leaf joint of the plant. Remove the leaf before the sprout and then twist the sprout away from the plant. You can also cut them away with a clean, sharp knife.
A second crop often starts to emerge after the first crop has been harvested. While these are just as edible they won’t be as compact as the first crop.
Incidentally, the leafy tops of the plant are also edible. They can be treated and cooked like collards. Cutting the leafy tops away also encourages the remaining vegetables to mature before the end of the growing season. This is known as topping.
Sprouts can be stored, unwashed in plastic bags in the refrigerator for a couple of months.
You can also lift entire plants. While they can tolerate light frosts, the plants won’t survive a harder frost. If the plants are still laden with vegetables as temperatures fall, you can lift the plant and store them in a cold dark location, such as a root cellar. From here you can continue to harvest your crop for up to 3 weeks.
Attractive, delicious and easy to grow. These versatile vegetables can, with a little care, be grown in most climates.
A reliable, and easy to care for addition to the vegetable garden. With a little extra care gardeners in even the warmest climates can successfully grow the Brussels sprouts plant.
Jen is a master gardener, interior designer and home improvement expert. She has completed many home improvement, decor and remodeling projects with her family over the past 10 years on their 4,500 sf Victorian house. She is also a passionate farmer who keeps goats, chickens, turkeys cows and pigs on her farm, and an instructor for her community’s Organic and Sustainable Farming project.