The Downside To Planting Cabbage Next To Basil That You Should Consider

There are multiple companion plants that will thrive next to basil, but some other plants can come with considerable downsides. Planting basil (Ocimum basilicum) with your cabbage (Brassica oleracea) offers some pest repellent properties for basil, but these two together can also be pretty competitive. You might find planting cabbage and basil together creates conditions where either plant can thrive that outweigh the potential pest control benefits. The two plants also require differing temperatures for flourishing plants, which makes it harder for them to survive when planted closer together.

Companion planting is a long-standing tradition in gardening, and is a practice where you grow plants together to enjoy the benefits each offer. These intended benefits can include pest control, weed suppression, improved pollination, and other crucial needs for the growth of healthy plants. With some plant combinations, the two are even believed to improve the flavor of the crop. Some gardeners like to pair basil with veggies because basil attracts beneficial insects such as parasitic wasps and green lacewings. The herb can also repel various pests including aphids and spider mites, making basil popular for planting with garden veggies like carrots. However, if you try to enjoy these same benefits with cabbage, you likely won't have good results.

Cabbage is considered a heavy feeder, and growing it requires deep, infrequent watering for rich, full heads of crisp leaves. Basil needs consistently moist soil for its adequate growth, so growing the two as companions means they may easily compete with each other for water when planted closely together. Required sunlight is another consideration, as six to eight hours of full sun are best for both plants. As it reaches for the sunlight with its wide, spreading leaves, the cabbage can easily shadow young plants, blocking the basil's sun exposure and causing poor growth. 

Weather also plays a large role in making basil and cabbage unsuitable garden buddies. Like other members of the Brassica family, cabbage prefers cooler weather and has a low tolerance for high temperatures. They grow best in temperatures between 60 and 65 degrees Fahrenheit. The cabbage weather preferences are less than that of basil, which thrives with temperatures around 70 degrees to 75 degrees Fahrenheit. Even if you were to overcome the heavy competition for resources among the two plants, growing the two would present difficulties for temperature control. Instead of planting basil with cabbage, consider other great companion plants for growing with cabbage, such as dill and borage.