Plant Problem Diagnosis Key / Nutrient problems
Nutrient
Boron deficiency
B
Boron builds cell walls in growing points. When short, tips die and stems and fruit crack. The gap between too little and too much is narrow.
Signs
- Growing tip stunts, distorts and may die.
- Misshapen young leaves; hollow stem in broccoli and cauliflower.
- Poor fruit set; cracked or corky roots in carrot and beet.
What favors it
Sandy or high-pH soils, dry spells, and heavy liming.
Prevention
- Test soil for boron before adding any; the gap between enough and toxic is narrow.
- Include boron in hydroponic micronutrient mixes at the recommended rate.
Often confused with
NutrientCalcium deficiency (and tipburn)
Growing conditionsHerbicide injury
PestBroad mites and cyclamen mites
Sources
- The Importance of Boron in Vegetable Crop Nutrition in North CarolinaNC State Extension
- Boron DeficiencyUMass Extension
- Boron Recommendations Based on Soil Tests for Vegetable CropsUniversity of Maryland Extension
Treatment by crop
Cultural, biological and chemical options in the order to use them, and notes written for each crop.
Identification is free. Treatment is on the Home and Pro plans.
Questions in the key that lead here
- Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
No, only damage or discoloration - Where is the problem?
Leaves - What does the leaf damage look like?
Color change without distinct spots - Where did the color change start?
Newest, upper leaves - What do the new leaves look like?
Distorted, burned at the tips, or the tip dies - What else is going on?
Growing tip dies; stems brittle, cracked or hollow
Not a match? Start the key or describe what you see.
More photos
More from university Extension: search Extension pages on boron deficiency, or find a plant diagnostic lab through your state's Extension.