What homemade solution kills tomato blight effectively?

Written by

Reviewed by

Published: October 23, 2025

Updated: October 23, 2025

Homemade remedies can be organic solutions to tomato blight if applied correctly. Baking soda spray works by causing the leaves to become alkaline, which inhibits fungal growth. To be effective, mix 3 tablespoons of baking soda into a gallon of water, adding 2 tablespoons of fish emulsion to the solution. This spray must be applied to the leaves only when the temperature is below 85°F (29°C) to prevent leaf burning.

Homemade Blight Treatment Comparison
Solution	Preparation	Application	Effectiveness
Baking Soda Spray	3 tsp soda + 2 tbsp fish emulsion per gallon	Weekly; morning <85°F	Moderate prevention
Milk Solution	Equal parts milk and water	Every 5 days; morning dew	Low to moderate control
Vinegar Mix	2 tbsp vinegar per gallon	Biweekly; avoid direct sun	Limited efficacy
Garlic Extract	10 crushed cloves steeped 24 hours	Weekly; full coverage	Mild deterrent

Always test solutions on single leaves before full application

Homemade Blight Treatment Comparison

Solution

Baking Soda Spray

Preparation3 tsp soda + 2 tbsp fish emulsion per gallonApplicationWeekly; morning <85°FEffectivenessModerate prevention

Solution

Milk Solution

PreparationEqual parts milk and waterApplicationEvery 5 days; morning dewEffectivenessLow to moderate control

Solution

Vinegar Mix

Preparation2 tbsp vinegar per gallonApplicationBiweekly; avoid direct sunEffectivenessLimited efficacy

Solution

Garlic Extract

Preparation10 crushed cloves steeped 24 hoursApplicationWeekly; full coverageEffectivenessMild deterrent

Always test solutions on single leaves before full application

Proper application techniques make homemade treatments more effective. Use a fine mist sprayer to cover completely both leaf surfaces. Apply when moisture is present in the morning; usually, the breezy hours are best. When dew is present, the medicinals adhere well. I add 1 teaspoon of vegetable oil to help the remedy adhere better. Repeat the treatment after heavy showers to maintain protection.

Effectiveness Limits

Works best for prevention not active outbreaks
Requires consistent application every 5-7 days
Temperature constraints: baking soda <85°F
Combine with cultural controls for best results

Safety Precautions

Avoid spraying open flowers to protect pollinators
Test solutions on single leaves before full application
Wear gloves to prevent skin irritation
Store unused solutions for maximum 48 hours

Performance Boosters

Add 1 tsp neem oil to enhance antifungal properties
Combine baking soda and milk solutions
Apply after rain when humidity favors infections
Use soft water to prevent mineral buildup

Utilize natural antifungal proteins derived from milk solution. Use whole milk, not skim, for the best effect. The proteins found in whey cause protective films to form on the leaves. Apply every five days in times of high humidity. I have found that applying it in the morning, during existing dew, greatly increases coverage.

Set reasonable expectations for home treatments. These treatments are more effective when used in conjunction with early detection for prevention. During large outbreaks, follow up with a copper fungicide for better control. Be sure to remove all affected leaves first. Homemade treatments decrease the need for chemicals but will not cure advanced infections.

Read the full article: Tomato Blight Treatment Guide: Control & Prevention

Share on Facebook Post on X Share on LinkedIn