Alliums
Allium plants, like garlic, onions, and chives, are top-notch cauliflower companion plants if you want to keep pests at bay. These plants contain sulfur compounds that mask the scent of nearby cauliflower and other crops that pests love. The scent of alliums also repels deer, aphids, and cabbage loopers.
Sage
Cabbage moths are some of the most destructive pests of brassica crops; they can quickly leave cauliflower leaves in tatters. However, the strong scent of sage keeps these troublesome pests away and helps protect cauliflower from flea beetles. While sage plants are primarily grown for their edible leaves, these culinary herbs also produce pretty purple flowers that lure bees and other vital pollinators to the garden.
Dill
Dill is a good cauliflower companion plant since they have similar growing needs and thrive in the cool weather of spring and autumn gardens. Beyond that, dill plants are relatively small, so they can be easily squeezed in between rows of cauliflower and other crops to save space in your garden. Dill attracts hoverflies and parasitic wasps that feed on cabbage loopers and keep your cauliflower plants pest-free.
Hyssop
DEAN SCHOEPPNER
Hyssop is a less common addition to vegetable beds, but it is a great cauliflower companion plant and a good choice for other brassicas when pests plague your garden. Hyssop plants deter many insects, including flea beetles and cabbage moths. Deer also avoid these fragrant plants. While hyssop plants are certainly functional, they’re also attractive, with purple flowers that add color to the garden and provide nectar and pollen for bees.
Radishes
CAMERON SADEGHPOUR
Like cauliflower, radishes grow best in cool weather, usually planted in spring and autumn. Compared to most other vegetable crops, radishes are incredibly fast-growing; some mature in just 21 days. If you’re looking to fill up empty space around the base of your cauliflower plants and pack more edible crops into your garden, radishes are good cauliflower companion plants.
Beets
BOB STEFKO
Beets are another low-growing vegetable that thrives in cool weather and has growing needs similar to cauliflower, making them perfect partners in garden beds. Cauliflower and beets prefer rich soil and regular watering. They're both among the first vegetables to plant in spring and thrive in chilly autumn gardens, too. Like radishes, beets can be planted in the empty soil around cauliflower plants to increase garden yields, and you don't need to worry about low-growing beets competing with cauliflower plants for sun.
Other Brassicas
With companion planting, you typically want to avoid growing similar crops together because plants in the same plant family can fall victim to the same pests and diseases. However, brassica crops are often grown together because they have similar care needs, and you can treat them all for pests at the same time. Planting cauliflower with broccoli, Brussels sprouts, and other brassicas makes it much easier to cover all your vulnerable crops with floating row covers or treat them with Bt thuricide if cabbage loopers invade.
Spinach
DENNY SCHROCK
Spinach is a champion in cool-season gardens and makes a good cauliflower companion plant in spring and autumn beds. When grown as companions, cauliflower plants provide shade to low-growing spinach, which can keep spinach plants from bolting as quickly at the end of spring. In return, spinach plants shelter the soil with lush leaves that help suppress weed seeds and slow soil evaporation rates.
Yarrow
Yarrow is primarily grown in ornamental beds, and its broad, flat blooms are highly attractive to an assortment of pollinators. Yarrow flowers are also magnets for predatory insects, such as ladybugs, lacewings, and hoverflies, which feed on some of the most common cauliflower pests. When planted in vegetable gardens, yarrow helps shield cauliflower and other brassicas from destructive insects and looks pretty while doing so.
Nasturtium
DOUG HETHERINGTON
Nasturtium plants are also sometimes used in ornamental beds, but their leaves, flowers, and berries are edible and make tasty additions to salads and other recipes. When grown as a cauliflower companion plant or with other brassicas, nasturtiums act as trap crops, luring aphids and other pests away from more vulnerable vegetables. Depending on the size of your garden, you may want to grow mounding rather than trailing-type nasturtiums; mounding plants don’t take up as much space in small gardens.