Tony O’Neill, gardener and author of the popular “Composting Masterclass” and “Your First Vegetable Garden,” combines lifelong passion and expert knowledge to simplify the art of gardening. His mission? Helping you cultivate a thriving garden. More on Tony O’Neill
When planning where to plant your cabbages, take a minute to consider what is, or will be planted nearby, as there are benefits and disadvantages you need to consider.
Some nearby plants will boost your cabbage growth by providing nutrients, others will deplete nutrients by stealing them for themselves, some will help protect them from pests and diseases, and some are just neutral, so they are not a threat but can be a good friend to them nonetheless.
Also, consider how companion plants can help protect your crop, not just in what they do to the soil but in how they help the garden’s biodiversity, attracting pollinators and predatory insects to eat the pests that can spoil your cabbage crop.
Once you’ve considered companion planting in terms of nutrients and pest control, give a wider thought to environmental factors such as wind, rain, and sun – remember that cabbages like a little bit of light shade from the hottest sun in high summer, but need light and sunshine for the rest of the year, so tall, but not thick planting that gives a bit of shade at the height of summer can help too.
We will now look in more depth at how to use companion planting and what you need to avoid.
Beneficial Cabbage Companions
Adding pest-repelling aromatic herbs such as Lavender, Thyme, Cilantro, Dill, Mint, Sage, or Chamomile (but not Fennel, which can disrupt cabbage growth) can help repel the white cabbage butterflies which feed on cabbage plants and lay eggs that turn into caterpillars which start the whole feeding cycle again, and not many pests like the smell of Celery, so use this to your advantage.
Edible flowers such as nasturtiums, and those summer garden flowers which give great color that we all like to see, such as marigolds and petunias, and larger shrubs such as Borage will all attract predatory insects that feed on the main cabbage pests.
Plants that hang over the top of the cabbage, such as chives and the other herbs listed above, can deter pests from that local area and create a protective umbrella that deters many of the pests that otherwise would need protection against by netting or the use of harmful chemicals and expensive repellent sprays.
If you are growing in a small space and feel you don’t have room to plant nearby or between your cabbages, growing small herbs such as Basil, Rosemary, or Thyme in pots and placing them near your crops may be the answer – and you can move them around as crops are taken out and new seedlings are planted – and of course, you always have them to hand for culinary use.
Beneficial Insect-Attracting Plants
Encouraging predatory insects into your garden that eat the pests that cause the damage before they cause the damage is a clever strategy.
Dill, which repels some cabbage pests, also attracts lacewings, which predate on cabbage pests such as aphids.
Marigolds also attract ladybugs and hoverflies that eat sap-suckers such as aphids, whiteflies, scale insects, leafhoppers, Chamomile, Daisy, and any variety of Mint will attract predatory insects.
Low-growing Mint, Rosemary (with a strong menthol smell and deters thrips), and Thyme can shelter beetles and other beneficial insects.
Soil Improvement and Nutrient-Sharing Plants
Beans and Peas are known to fix nitrogen in the soil, so they are a useful close companion to the cabbage, and tall beans can be planted to provide a little helpful shade on the hottest days.
Beets, Beetroot, Turnip, and Swede all drop leaves during the season, which contain a high concentration of magnesium, so dig the fallen leaves from them into the soil around your cabbages as they fall to give them a magnesium boost.
Deep-rooted vegetables like carrots and parsnips pull up nutrients from further down in the soil where cabbage roots can’t reach, and some of this gets shared on the way.
This also improves soil health by spreading the nutrients around and ensuring no pockets of specific nutrient-poor soil could affect your cabbages.
We have mentioned Chamomile as a crop that attracts predatory insects. Still, it, along with other companion plants such as Marjoram and Summer Savory (a herb traditionally used to cure bee and wasp stings), all release substances into the soil that encourage the increased growth of nearby plants and are said to improve the flavor of their fruit!
Cabbage Companions to Avoid
Allelopathy is “a common biological phenomenon by which one organism produces biochemicals that influence other organisms’ growth, survival, development, and reproduction.” One plant, therefore, releases chemical compounds that affect another.
Allelochemicals are released into the environment from roots (into the soil) and by the decomposition of leaves falling to the ground. Lemons, for instance, contain the allelochemical leptospermone, which can affect nearby plants. Studies have shown that the yield of cabbages and lettuces can be affected in an area where lemons are grown.
Allelopathy, of course, can be a good thing – cabbages are allelopathic themselves, but when planting them, it is useful to consider how other plantings could affect your cabbage crop – Broccoli, for instance, can be allelopathic to later-planted broccoli or any other brassicas, so perhaps not a good idea to plant your cabbages where last year’s broccoli sat.
As a general rule, avoid planting any crop from the same family where one has been previously.
Mustard plants are also allelopathic, with many species producing sulfur compounds called glucosinolates. These break down in the soil to release allelopathic products.
Growing cabbages (or any brassicas) close to other crops or plants may result in competition for nutrients – so avoid, if you can, or provide selective top-up feed to your cabbages to replace these nutrients lost to close companion plants.
Cabbages are shallow-rooted, so hungry shallow-rooted plants nearby may compete for the same nutrients. Strawberries, for instance, are also shallow-rooted and need to take as many nutrients as possible to produce fruit.
Any plants hungry for Calcium, Magnesium, Nitrogen, Sulfur, or Zinc will compete with your cabbages if planted close together.
Hungry plants competing for the same nutrients in the area should be avoided where possible.
An under-fed cabbage is susceptible to disease, so look out for Rue, an ornamental herb you may have growing nearby, which removes calcium from the soil; Strawberries, as we have mentioned, whose shallow roots compete with cabbages for the same nutrients, can leave cabbages under-nourished; and Outdoor Tomatoes, which as they grow earlier in the season, can take out the available nutrients before the poor cabbages get a chance!
Companion Planting Layouts for Cabbage
As mentioned, tall companion plants such as peas and beans can shade cabbages from the hottest sun and help fix nitrogen in the soil, aromatic herbs that hang over the cabbages can repel pests, and predatory insects attracting flowers nearby can all assist in success with cabbage crops.
Beets work well with cabbages, keeping the roots moist and helping to deter common cabbage pests, as their leaves contain chemicals that repel root maggots.
Cabbages have a relatively long season, so planning similar long-season crops or shorter-season crops in succession is often a useful strategy. Celery can be left in for the season, and its smell deters harmful insects and attracts helpful ladybugs and lacewing larvae.
Alliums such as garlic and onions have a strong smell that repels insects and other pests that threaten your cabbages – such as worms, slugs, moles, and rabbits – it is useful to plant around the edge of your garden to protect a wider area.
Cabbages are one of the crops that should not be planted in the same place year after year, as the soil can be depleted of the specific nutrients they need, and it can harbor pests and diseases from one season to the next – so to give your plants the best chance you should always rotate your crops.
When considering how you will plan for crop rotation on the available land, you can always plan to keep beneficial companion plants nearby, just not in the same soil. You will still benefit from companion planting, allowing the soil to recover following the crop used in that area before replanting with something else the following season.
Traditionally, Potatoes follow Brassicas (the family that includes Cabbages) in a Three-Year Cycle rather than the other way around – potatoes churn up the soil for salads, legumes, and onions. Cabbages follow as they benefit from the harder ground, and then the potatoes churn up and refresh the soil again, starting the cycle over.
Polyculture can be described as planting two or more different and useful plants in the same space simultaneously. As a practice, it has been around since ancient times. Still, we often forget that companion planting can improve the soil, help plants draw nutrients from the soil, repel pests, and attract beneficial bugs, predatory insects, and wider pollinators that help the whole garden.
We have already discussed using plants of height, those that pests don’t like the smell of, and those with different root systems that can help or hinder your cabbages. So, consider the available space and plan to incorporate beneficial companion plants while avoiding others.
Just because one plant can affect another doesn’t mean they can’t be in the same garden. Just keep them in a different soil area!
Don’t forget, while trying to protect your cabbages, think about what they can do to protect others. Cabbages provide good wind protection for young seedlings such as Celery, and crops such as Spinach thrive when planted near cabbages.
FAQs on Cabbage Companion Planting: What to Grow and What to Avoid
What can I plant next to the cabbage?
Companion plants that benefit cabbage include pest-repelling plants like marigolds, sage, thyme and herbs that attract predatory insects like lavender, dill, mint, and chamomile. Soil-improving plants like beans, peas, beets, turnips, and carrots can also be planted nearby. Avoid planting allelopathic plants and nutrient-competing plants like strawberries and broccoli.
What herbs protect cabbage?
Several herbs can protect cabbage from pests and insects, such as marigolds, sage, thyme, and lavender. These herbs have natural repellent properties and can attract beneficial insects to the garden that feed on cabbage pests. Planting them as companions for cabbage can help reduce the need for harmful pesticides and improve overall crop health.
Can cabbage be intercropped?
Yes, cabbage can be intercropped with various plants, including beneficial companions for pest control and nutrient sharing and plants that attract predatory insects and pollinators. However, when choosing companion plants, it’s important to avoid planting allelopathic or nutrient-competing plants nearby and consider environmental factors like wind, rain, and sun.
You are planning what will go where in the garden is something to look forward to rather than a chore to avoid. It’s a great winter task and can be combined with planning for seed purchase, splitting and propagating new plants from existing stock, checking your tools and equipment are ready for the growing season, and planning any landscaping changes such as the introduction of raised beds or trying new methods such as planting in buckets and containers.
Companion planting is at the heart of this – so work around what to avoid putting too close together, and fill in the gaps with those plants that help each other.
Also, remember that you can constantly change plans as the season goes on, as new seedlings are ready to be planted out, as crops are taken for use in the kitchen, or old plants are taken out at the end of their productive cycle, and the land can be used for something else.
With careful consideration of how plants can work together naturally to enhance your yield, you can limit pest damage, nurture the soil and save time and effort while reducing the cost of additional fertilizers and protective sprays by thinking ahead.