Beetroot (Beta vulgaris) is a root vegetable grown from a seed, not a true bulb like garlic or onion. The confusion arises because the edible part is the swollen, underground storage root. Cultivating this root requires specific conditions and steps to ensure a successful harvest.
Understanding Beetroot’s Growth Cycle
Beetroot is a cool-season crop that thrives in moderate temperatures, typically between 50°F and 85°F, making it suitable for spring and fall planting. The plant requires full sun exposure, meaning at least six hours of direct sunlight each day, as the leaves feed the developing root. Planting too early, exposing the plant to prolonged cold, can cause it to “bolt,” prematurely sending up a flower stalk and focusing on seed production instead of root enlargement.
The growing period is generally 50 to 70 days for a harvestable root, varying by cultivar. Varieties are chosen based on shape, such as round globe types or elongated cylindrical kinds. The leafy greens are also edible and nutritious, offering a dual-purpose harvest. Selecting a bolt-resistant variety can help prevent premature flowering when planting during warmer periods.
Preparing the Soil and Planting Location
Successful root development depends heavily on the quality of the planting medium, which must be loose and free of obstructions. Beetroot requires a well-draining soil structure, such as a sandy loam, allowing roots to expand symmetrically without becoming misshapen or “forked.” Compacted or heavy clay soils should be avoided or amended, as they restrict root growth. Rocks or large debris can also cause the developing root to split or grow irregularly.
Beetroot prefers a slightly acidic to neutral soil pH, ideally ranging from 6.0 to 7.0. If the soil is too acidic, it may hinder the uptake of phosphorus and potassium, which are important for root formation. Incorporating well-rotted compost or aged manure improves both fertility and drainage. Avoid excessive nitrogen, as this promotes lush leaf growth at the expense of root swelling.
Sowing and Initial Seedling Management
Sow beet seeds directly into the prepared garden bed, as the roots are sensitive to disturbance and transplanting can stunt growth. The “seed” is actually a multigerm cluster containing two to six individual seeds encased in a dry fruit capsule. This means multiple seedlings often sprout from a single spot, making subsequent thinning necessary.
Sow the seed clusters about one-half inch deep, spacing them one to two inches apart in rows a foot or more away from each other. Germination typically occurs within 10 to 20 days, depending on soil temperature and moisture. Once seedlings emerge and develop their first true leaves, the crucial step of thinning must begin.
Thinning involves removing weaker seedlings to leave only the strongest plant at each interval, providing room for the root to swell. For full-sized roots, plants should be spaced three to four inches apart. Use small scissors to snip unwanted seedlings at the soil line rather than pulling them, which prevents disturbing the delicate roots of the kept plant. The small greens removed during thinning can be added to salads.
Essential Care for Root Development
Consistent moisture is necessary for the formation of tender, uniform roots, as inconsistent watering leads to tough, woody, or cracked beetroot. Plants require about one inch of water per week, and the soil should be kept consistently moist but never waterlogged. Watering deeply and regularly is preferable to shallow watering, as it encourages a strong root system.
Applying mulch, such as straw or shredded leaves, helps maintain soil moisture and keeps the soil temperature cool. Weeding is important, especially in the early stages, because small seedlings cannot compete well with aggressive weeds for resources. When weeding, take care not to damage the shallow-growing roots.
Use a fertilizer lower in nitrogen and higher in potassium and phosphorus to encourage root expansion. Excess nitrogen causes the plant to prioritize leafy growth, resulting in small roots. Common issues include leaf miners and Cercospora leaf spot, a fungal disease. Ensuring good air circulation and avoiding overhead watering helps mitigate fungal problems.
Harvesting and Post-Harvest Handling
Beetroot is typically ready for harvest when the exposed tops, or “shoulders,” of the roots reach a diameter of 1.5 to 3 inches. Smaller roots are often the most tender and sweet; allowing them to grow much larger than a tennis ball can result in a tough and woody texture.
To harvest, gently loosen the soil around the root with a garden fork, or grasp the foliage at the base and pull the root straight out. If the soil is dry, watering the bed the day before harvest makes the process easier. Once harvested, remove the greens immediately to prevent them from drawing moisture out of the root, which causes shriveling.
Cut the greens off about one inch above the root, but do not cut into the root itself, as this causes the red juices to bleed out. The roots should not be washed, but large clumps of soil can be gently removed. Storing the unwashed roots in a plastic bag in the refrigerator keeps them fresh for a week or two, or they can be layered in damp sand for long-term winter storage.