Prevent Tomato Blight Naturally with this Spray
Growing tomatoes is easy until it's not. One day everything looks great, and the next you're spotting brown and black spots creeping across your leaves. Blight is one of the fastest ways to ruin an otherwise solid tomato season; the good news is you don't need anything complicated to stay ahead of it.
Tomato blight spray recipe (works as both prevention and a first response)
Ingredients:
- 1/4 tsp baking soda (heaped)
- 1/4 tsp vegetable oil
- 3 3/4 cups water
- 1/4 tsp dish soap
Equipment:
- A reCAP Mason Jar Sprayer Lid
- A 32 oz regular mouth Mason jar
How to make it:
- Add all ingredients to your Mason jar.
- Attach the sprayer lid.
- Shake gently to combine.
- Spray your tomato plants every 7 to 10 days.
*Important: don't spray when temperatures are above 90°F, as this can damage the leaves.
What is tomato blight? A fungal disease affecting tomatoes and potatoes, usually showing up as brown or black spots on leaves, stems, or fruit, and yellowing, dying leaves. Early blight causes brown spots on leaves, stems, and fruit; late blight is more aggressive and can rot fruit quickly; Septoria leaf spot causes smaller spots, usually starting on lower leaves.
What actually causes it? Blight thrives in moist, stagnant conditions: wet leaves and poor airflow create problems. Water at the base of the plant (not the leaves), water in the morning so plants can dry during the day, space plants 18 to 24 inches apart, remove leaves showing early signs, prune lower branches below the first flowers, remove heavily infected plants entirely, and spray preventatively every 7 to 10 days.
Why this works: Baking soda creates a less friendly environment for fungus, soap helps the solution stick to leaves, and oil helps spread coverage evenly. Simple, but effective when used consistently.
Keep it in one jar, start to finish. Mix, store, and spray your blight treatment right from the same jar: a reCAP Mason Jar Sprayer Lid turns any Mason jar into a reusable garden sprayer, no separate bottle needed.