Fusarium Control

Fusarium Wilt & Root Rot Control — Biological Prevention That Works

Fusarium oxysporum is a soilborne fungal pathogen that invades plant vascular tissue, cutting off water and nutrient flow from the inside out. Once a plant is infected, there is no cure — which makes prevention and early intervention the only effective strategy. Biological fungicides applied at transplant and throughout the crop cycle are your best defense.

How to Identify Fusarium Wilt

• Plants wilt during the day but partially recover overnight — a classic early sign
• Lower leaves yellow and drop; wilting becomes progressive and irreversible
• Asymmetric symptoms: sometimes only one side of a leaf or one branch is affected
• Cut stem cross-section reveals brown or dark vascular tissue
• Warm soil temperatures (above 82°F) and acidic soils favor rapid spread

How Fusarium Enters Your Crop

The pathogen enters through root wounds caused by transplanting, cultivation, or feeding damage from harmful nematodes. It then colonizes the vascular system, blocking water uptake and causing the characteristic wilt. Spores persist in soil and plant debris for years, making sanitation and biological suppression essential.

Biological Control & Prevention Strategies

• Apply biological fungicides at transplant — products containing Trichoderma spp. or Bacillus subtilis colonize roots and outcompete Fusarium before it can establish
• Maintain soil biology — compost teas and beneficial microbes support a suppressive soil environment
• Manage soil pH — slightly alkaline conditions (pH 6.5–7.0) reduce pathogen activity
• Sanitation — clean and sterilize pots between crops, use fresh growing media, source certified disease-free transplants
• Use resistant varieties where available, especially for tomatoes, basil, and cannabis
• Avoid root injury during transplanting and cultivation to reduce entry points

Crops Commonly Affected

Tomatoes, cannabis, strawberries, basil, cucumbers, peppers, ornamentals, and many field crops. Fusarium is especially damaging in warm greenhouse environments and hydroponic systems where it can spread rapidly through recirculating water.

Additional Resources

• Formidable Fusarium — Ann Chase, Greenhouse Magazine
• Not sure which product to use? Complete our Grower Questionnaire for a personalized recommendation.