1. Use a fertilizer which contains B.
2. Corrective drench application of borax or solubor at 6.25 ppm of B for soilless substrates. Visible improvements with the use of the corrective B fertilization will be very slow and it is difficult to reverse growing point death or distorted leaves. For corrective application: add 0.75 oz. (21.3 g) of borax (11% B) per 100 gallons of water or 0.43 oz. (12.2 g) of solubor (20% B) per 100 gallons of water. Rinse off foliage.

Foliar sprays have a greater risk of plant injury. Avoid applications during the midday heat. Plant uptake is enhanced by prolonged drying time, which occurs during humid conditions, especially in the morning. Nutrient uptake through the leaves is also greater in the day than at night, making morning applications more desirable than evening sprays.