For many old gardeners, growing brussels sprouts is considered to be an essential winter crop in the garden. Unlike the old sprout varieties, the modern F1 hybrids are sweeter and more tender than ever, making them ideal for new vegetable gardeners to grow.
Brussels sprouts are tough plants that are fairly easy to grow if you give them good soil, protect them from caterpillars and give them a good start early in the year.
In this article we tell you the secret to growing brussels sprouts successfully.
Choosing A Variety To Grow
When choosing which variety to grow, there are two main options: heritage varieties and F1 hybrids.
The old heritage varieties are very reliable. They have been grown for years and are proven to be worth growing. And you can also save the seeds for next year’s crop.
Evesham Special: This heritage variety is a heavy cropper, which will start early and go on over several months. It’s a hardy plant, so can be planted on exposed sites.
- Heavy, early crops over several months
- Medium sized plants, ideal for exposed sites
- Good source of vitamin C and folate
Red Ball: As the name says, you will get dark red sprouts. They look a bit like tiny red cabbages. Although the yield is smaller than with green varieties, their mild, delicate nutty flavour makes up for that. Definitely worth a try in my opinion.
- Days To Maturity: 90. Days To Germination: 7-14. Planting Depth: 1/8 inch. Spacing, Row: 24-36 inches.
- For an early crop start seeds indoors in the earliest part of spring. Or direct sow seeds outdoors in late Spring after last frost.
- When seedlings are 2 inches tall indoors, thin to 2 inches apart or transplant to individual pots.
Hybrid F1 Varieties
Although with hybrid F1 varieties you cannot save seeds from, and they are usually relatively new they have the advantage of being sweeter. This is one case when growing F1 hybrid varieties might be worth considering.
Green Marble F1: This is a popular variety for growing brussles sprouts for Christmas dinner. They have a traditional taste and are lighter in the centre. The yield you will get is high as well.
- Good variety for Christmas sprouts
- High yields of smooth
- Attractive lighter centre and good traditional flavour
Crispus F1: This variety has good club root resistance and produces dark green sprouts. It’s a hardy plant that tolerates any soil.
Growing Brussels Sprouts From Seeds
Brussels sprout seeds should be sown in March and April. I always recommend sowing sprout seeds indoors in pots as this gives far stronger plants that will shoot up once they are transplanted out into the garden.
Choose a good quality multi purpose compost for brussels sprouts as they are heavy feeders even when small. Plant two or three seeds per pot and prick out all but the strongest seedling after they are 2.5cm (1in) tall.
Sowing a few different varieties gives you the ability to get harvesting as early as September right until late February.
Planting & Caring For Your Sprouts
Transplanting begins when the plants have 3-4 good strong leaves. Do not allow the plants to get any larger in pots as they will quickly become root-bound and will then struggle to get established quickly in the ground.
You want a sunny spot for your brussels sprouts plants, ideally also sheltered from strong winds.
Planting in the right soil is essential for sprouts, they are a long season crop. They are also heavy feeders and really need to be grown in soil that has recently been manured.
An artificial feed like blood, fish and bone can be used but really isn’t a good enough alternative. If there is any crop in the garden that really requires well-rotted manure, it is brussels sprouts.
Top Tip: To give your sprout plants the best chance, water them before and after you transplant them.
Space your brussels sprout plants 50cm (20in) apart in rows 60cm (2 feet) apart.
When planting, be sure to firm the plants around the stem. Brussels sprout plants really do enjoy being firm in the ground.
Make sure you provide your brussels sprouts plants with support. Staking your plants is very beneficial as they quickly become top heavy and want to fall over.
Water them regularly until they have established themselves. In dry weather, make sure you water them every 10 days or two weeks. This will keep them in top condition.
Come September, they will start to grow quite a bit on top, so put more soil around the stem. This will make sure they can handle the weight.
Harvesting Brussels Sprouts
Once established in the ground, brussels sprout plants quickly grow tall and sturdy, it can take quite a while to get a harvest even at this stage. To encourage an earlier harvest, a liquid seaweed seed will encourage the plant to begin growing the sprouts.
- Seaweed plant fertilizer promotes strong growth, increased crop yields and lush foliage
- Contains a high concentration of seaweed, known for its unique anti-stress compounds
- Also includes extra iron and plant based amino acids that feed garden plants and improve yield
From early harvests you can begin harvesting sprouts as early as September (depending on the variety) but it’s worth remembering that brussels sprouts do taste better after a hard frost.
Harvests can continue for many months if the plants were sown in succession. Expect harvests as late as February or March.
Harvesting the sprouts is easy. Pick individual sprouts from the plant as they grow in size – usually the first sprouts will be at the bottom of the plant. Heritage varieties will usually offer a harvest over a longer period than F1 hybrid varieties that tend to ripen all at the same time.
The sprouts grow from the bottom up, so start harvesting from below.
At the end of your harvest period, don’t disregard the leaves. Because they are delicious. Similar to cabbage leaves, but more tender.
I love to sauté them with bacon, onion and garlic. It’s delicious.
Pests And Diseases That Can Affect Brussels Sprout Plants
No guide about growing brussels sprouts would be complete without a mention of common pests and diseases that could cause problems.
There are a number of pests that will be after your sprout plants, including caterpillars and birds.
Brussels sprouts are part of the cabbage family and pigeons love them. They can decimate your seedlings in no time.
So you have to put preventative measures in place:
- Cover your brussels sprouts seedlings with cloches or the top half of a plastic bottle, such as a squash bottle. Leave the bottle top off to keep air circulation going.
- When your plants are bigger, you can cover them with netting to prevent the pesky pigeons from getting to the leaves.
Another pest that might affect your sprout plants is the cabbage root fly. The female cabbage root flies will lay their eggs on the soil and their larvae will then feed on the roots just below the soil surface.
The cabbage root maggots are white and about 5cm (2in) long. They can stunt the growth of the plants and even kill your plants.
Because they operate below the soil, you will only know that your plants are affected, when they start to wilt and die.
So prevention is the key. And the best way to prevent the larvae from getting to the roots is to prevent the female flies from laying their eggs around the stems of the plants.
You can use insect-proof mesh or horticultural fleece to cover your plants. This will also keep away birds, so another reason to use it.
Cover them as soon as you plant them out, to leave nothing to chance.
Brassicas are beloved by caterpillars, so they will feed on brussels sprouts. Several varieties of caterpillars will like the tasty sprout leaves, but the main one is the caterpillar of the cabbage white butterfly.
It’s easy to see if you have caterpillars, because they leave big holes in the leaves. And some you will also be able to spot easily. Although a lot of them are really well camouflaged.
You can try to pick off the caterpillars you see, but if you have a lot of plants, this can become a time-consuming task.
The best way to keep the caterpillars away is to cover your plants with insect-proof mesh.
You can also try companion planting. This is a method where you plant different plants together for mutual benefits. Onions for example will repel the cabbage white butterfly, so they won’t lay their eggs on your brussels sprouts.
Growing burssels sprouts successfully means you have to keep them free of diseases.
The main disease that can affect plants of the brassica family is club root.
Club root is a fungal disease that will cause the roots to swell and become distorted.
It can lead to stunted growth, reduced yield and potential death of the plant.
The main sign of an infection is the swollen roots, but you can also see signs above ground. The growth will be stunted, and the foliage will have a purple tinge to it. In hot weather, the leaves might start to wilt, because the roots are unable to provide them with the necessary water.
Once a plant is affected there isn’t anything you can do, apart from pull it up and destroy it. Do not compost infected plants, as the diseases can leave on in the soil.
So the best defence is prevention. Here are some things you can do to prevent an infection:
- Practice crop rotation – this should include all plants from the brassica family. Club root can stay in the soil for decades, so once you know it’s in the soil, it will take a long time to get rid of it.
- If you know that you have the disease in the soil, the only way to have homegrown sprouts is by growing brussels sprouts in pots.
- Clean your tools after using them in infected soil to avoid spreading the disease to other parts of the garden.
- Buy seeds and plants from reputable sellers who can guarantee them to be disease free. Be careful when you accept plants from fellow gardeners.
- Warm and moist soil provides the ideal conditions for club root, so make sure you have good drainage.
- Weed your beds regularly, as some weeds can attract the disease.
- There are some varieties that are said to be resistant to club root, such as Crispus F1. Although there is never a guarantee.
- You can also raise the pH level of your soil to reduce the risk of club root. This can be done by adding lime.
If you don’t know the pH level of your soil, you can buy DIY soil pH test kits.
- 【Premium Quality】: 100 test strips made of premium quality filter paper. Perfect for garden, outdoor & indoor plant soil quality testing.
- 【Fast & Accurate】: The test range of soil pH test strip is 0-14. Accurate and reliable test results can help you analyze the soil.
- 【Convenient Operation】: The first step is to use one tablespoon put 8 level tablespoons (4 ounces) of soil sample into a clean cup and mix it with 8 level tablespoons (4 ounces) of water for 30 seconds. The second step, let the soil water solution stand for 30 minutes until stratification occurs. The third step is to dip a PH test strip into the solution, keep the soil test strip in the solution for 3 seconds, and match the color plate with the color table after 1 minute.
Garden lime is also easily available in garden centres or over Amazon.
- Use garden lime to bring the soil in your garden to a more optimum pH level improving soil structure and plant root efficiency
- This ready to use product provides an immediate change to the pH level of your soil once worked in
- Monitor your soil pH throughout the growing season to ensure an ideal level is maintained
Frequently Asked Questions
If you still have questions about growing brussels sprouts you might find the answer in our FAQ section.
Will Brussels Sprouts Come Back Every Year?
Brussels Sprouts are a biennial, which means they will come back after the first year.
In their first year, they will produce sprouts, which we can harvest and enjoy. In the second year, they will form flowers and set seed. Then they will die back. If you were to let the seeds drop on the soil, new brussels sprout plants would come up.
While it sounds like a good idea to keep getting free new plants, by growing brussels sprouts in the same spot every year, you risk the build up of diseases like club foot, which could infect your soil for decades.
Why Are My Brussels Sprouts Not Growing On My Plants?
If you don’t have sprouts your plants might not have enough leaves. The more leaves your plant has, the more sprouts you will get.
Leaves are used to produce nutrients, so fewer leaves means less nutrients and, as a result, fewer sprouts.
The reason you might have fewer leaves might be a lack of nitrogen in the soil. To remedy this problem, feed your plants with nitrogen rich liquid fertiliser.
To prevent this from happening in the future, make sure you plant your brussels sprouts in rich soil. You can achieve this by adding well-rotted manure or organic matter to your soil before planting.
Also, make sure you water your plants regularly in hot and dry weather, especially in late summer. Ideally, water them at least every two weeks, to keep the soil moist.
Now that we have told you the secret of growing brussels sprouts successfully, you are ready to give it a go. Happy Growing!