Plant Doctor

Symptoms

Brown, dry, crispy leaf tips. New growth may be distorted, curled, or stunted. In fruiting plants, you may also see blossom end rot (dark sunken spots on the bottom of fruit). Leaf edges can become ragged or torn.

Cause

Low calcium in the solution, pH too low (below 5.5), or high humidity preventing transpiration which moves calcium through the plant. Excess potassium or magnesium can also block calcium uptake.

How to Fix

1. Add calcium nitrate to the nutrient solution according to your nutrient calculator recommendations
2. Verify pH is between 5.8 and 6.5 for optimal calcium uptake
3. Increase air circulation around plants to encourage transpiration
4. Reduce humidity if it is consistently above 70%
5. Check that you are not overdosing potassium or magnesium

Prevention

Use a nutrient formula with adequate calcium. Maintain good air movement. Keep pH in the ideal range. If growing tomatoes or peppers, calcium is especially important during fruiting.