Rutabaga, a member of the Brassica family often mistaken for a large turnip, is a cool-season root vegetable grown for its swollen, creamy-yellow root. This crop benefits significantly from a gardening technique known as companion planting, which involves strategically placing different plant species near each other to enhance growth and provide natural protection. By understanding the rutabaga’s specific needs and vulnerabilities, gardeners can select plant pairings that create a mutually supportive micro-environment. This practice offers a natural, low-intervention approach to maximizing yields and maintaining plant health.
Rutabaga’s Growing Requirements
The rutabaga (Brassica napobrassica) is a heavy feeder that requires a consistently fertile soil base, typically thriving best in a slightly acidic to neutral pH range of 6.0 to 7.0. It develops optimally in cool conditions, preferring air temperatures between 50 and 65 degrees Fahrenheit, which makes it a suitable crop for late summer or fall harvests. As a Brassica, the rutabaga demands high levels of nitrogen and potassium to support the development of both its leafy top growth and its large storage root. A balanced fertilizer, such as a 10-10-10 blend, is often recommended for early growth, with a follow-up application of nitrogen a month after planting.
The plant is vulnerable to specialized pests and soil-borne diseases that target related crops. Common insect threats include the flea beetle, which chews tiny holes in leaves, and the cabbage aphid, which stunts growth by feeding on the foliage. Root-specific pests, such as the cabbage root maggot, can tunnel into the developing root, causing significant damage. Diseases like clubroot, black rot, and Alternaria leaf spot are also threats, particularly in wet or poorly rotated soils.
Plants That Help Rutabaga Thrive
Strategic companion planting offers the rutabaga protection by repelling common pests and enhancing the soil’s nutrient composition. Plants with strong aromas, particularly those from the Allium family, are highly effective at masking the rutabaga’s scent, making it difficult for pests to locate. Planting chives, garlic, or onions nearby can deter the cabbage aphid and the flea beetle, which rely on smell to find their host plants. Placing these aromatic allies in close proximity, such as 12 to 18 inches away, provides a protective barrier without creating competition for root space.
Certain herbs also provide pest-repelling benefits due to their volatile oils, acting as a natural pest confusion system. Rosemary, mint, and sage can be interplanted among the rutabaga rows to help discourage cabbage moths from laying eggs. Furthermore, some plants serve to improve the soil quality or structure, directly supporting the rutabaga’s heavy-feeding nature. Legumes such as peas and beans form symbiotic relationships with nitrogen-fixing bacteria, enriching the soil with bioavailable nitrogen compounds.
Peas are a good companion because they are cool-season crops that can be harvested early, allowing for beneficial rotation and nutrient sharing. Low-growing, leafy greens like lettuce can also be used as a living mulch, helping to suppress weeds that would otherwise compete with the rutabaga for moisture and nutrients. When using vining crops like peas, it is important to provide a trellis and ensure adequate spacing, typically around 24 to 36 inches, to prevent the rutabaga from being smothered by dense foliage.
Plants to Never Grow Near Rutabaga
Interplanting rutabaga with other members of the Brassica family is strongly advised against, as these plants share the same genetic vulnerabilities to pests and diseases. Crops such as cabbage, broccoli, kale, cauliflower, and turnips attract and host the same pests, including the cabbage worm and flea beetle. This concentration of shared hosts leads to a rapid buildup of pest populations, overwhelming the entire garden bed. Additionally, these plants can spread soil-borne diseases like clubroot and black rot more efficiently, which can persist in the soil for years.
Similarly, planting rutabaga next to other heavy-feeding vegetables results in intense competition for the same finite resources, specifically nitrogen and potassium. Large, nutrient-demanding crops like tomatoes, corn, and squash should be kept well away from the rutabaga planting area. Since rutabaga is grown for its root, any competition for nutrients directly limits the size and quality of the final harvest.
Another consideration is the potential for cross-pollination, which is a risk when planting rutabaga near close relatives like turnips and radishes, if the intention is to save seeds. While this does not affect the current season’s root harvest, it compromises the genetic purity of any saved seed, resulting in hybrid, non-true-to-type offspring in the following season.