How Deep Do Cabbage Roots Grow?

Root System

• A cabbage's root system is shallow, reaching 18 to 36 inches deep. Medium-rooting vegetables such as carrots (Daucus carota) have root systems that extend 36 to 48 inches deep while deep-rooting vegetables' roots can go 48 or more inches below the soil surface. Growing best in sandy or loamy soil with a neutral pH and full-sun exposure, cabbage does well when it has steady, even growth. Because it has a shallow root system, it benefits from a layer of mulch on its soil. Mulch conserves soil moisture and helps stabilize soil's temperature.

Plant Pairing by Root System

• Cabbage's root system spreads widely rather than deeply. As a consequence, cabbage should be planted alongside medium- or deep-rooting vegetables. Those plants' root systems will not interfere with cabbage roots, and the planting arrangement allows you to have a greater number of vegetable plants within a given space. Plan carefully before planting cabbage alongside other plants because different vegetables have different nutritional and soil requirements.

Companion Planting

• The term "companion planting" refers to planting compatible kinds of plants close together because they benefit and support each other. It allows more vegetables to be grown within the same amount of space than other gardening techniques, and, in some cases, the close plantings provide nutritional and/or pest-deterrent benefits. Cabbage can grow very successfully with medium-rooting vegetables such as carrots, beans (Phaseolus vulgaris) that grow in bush form and some herbs. Careful planning regarding the amount of space required between the kinds of plants is necessary.

  Herbs' naturally pungent odor helps to deter certain pests that otherwise would find those low-lying crops tasty treats. Before using the companion planting method, check whether or not the plants you want to use share similar pests or susceptibility to the same diseases because placing the plants too close to each other can lead to heavy infestations or infections. Do not plant cabbage with tomatoes (Lycopersicon esculentum) or beans designated as pole beans.

Growth

• Regular cabbage varieties can be spaced 12 to 18 inches apart, which provides adequate room for the roots to spread outward. Small and dwarf cabbage varieties can be spaced more closely. Starting cabbage seedlings indoors in containers allows you to get a head-start on the harvest; depending on weather and plant variety, two cabbage harvests per season are possible, one in early spring and the other after the first frost. If you start the seeds indoors, plant them 1/2 inch deep in soil, and thin the seedlings so only one seedling remains per container before transplanting the cabbage outdoors. Because of cabbage's delicate root structure, transplant the plants very carefully to reduce the amount of transplant shock.