Why Are My Beetroot Roots Splitting and Cracking?

Beetroot roots that crack, split, or develop longitudinal cracks running from crown to tip have experienced a sudden uptake of water after a dry period — the rapid rehydration of the root tissue causes the outer skin (which is less elastic than the inner tissue) to rupture. This is the same mechanism that causes tomatoes to crack. Uneven watering — periods of drought followed by heavy rain or sudden deep watering — is the primary cause. The roots are still edible once cracked but deteriorate faster and may allow soil-borne infections to enter through the cracks.

Why uneven watering causes cracking

The beetroot root is composed largely of water-filled storage cells. During drought, the outer skin remains at a fixed size while inner cells lose turgidity. When water suddenly becomes available — whether from rain, irrigation, or even just a temperature change — the inner cells rapidly absorb water and expand. The outer skin, which has not expanded proportionally, splits to accommodate the increased volume. A root that has experienced several dry–wet cycles develops progressively more severe cracking.

Prevention

Water consistently rather than deeply and infrequently. Light watering every three to five days in dry weather maintains more even moisture than weekly deep soaking. Mulching with 5 cm of compost, straw, or grass clippings around the beetroot row significantly buffers the boom-and-bust cycle by reducing evaporation and slowing the soil response to rainfall. This is the single most effective measure against cracking. Harvest beetroot before the roots become very large (10 cm+ diameter) — at extreme size the skin is under more tension and cracking is more likely.

Overwintered roots

Beetroot left in the ground over winter in heavy rainfall areas may develop significant cracking from winter wet-dry cycles, even without any management action. In wet climates, lift beetroot before hard frosts and store in boxes of just-damp sand rather than leaving in ground over winter. Roots stored this way remain crack-free and in excellent condition for three to four months.