Cause A boron deficiency.
Symptoms On leaves, necrotic crosshatching is on the inside of the petiole. Young leaves turn brown and die, resulting in a rosette of small dead leaves at the top of the beet. In the fleshy root, internal and external black spots of necrotic tissue develop.
- Apply boron to the soil with fertilizer or separately at 3 to 5 lb/A actual boron for table beets.
- Applying 1 lb/A actual boron as a spray on the foliage twice in midseason also gives good control of deficiency symptoms.