Blight Management Guide

Fungal diseases are a common problem for gardeners, and blight is one disease that can cause problems for your plants. Infected plants are often weakened and damage can occur. Taking steps to protect your plants from this disease is important. We’ve gathered information to help you prevent and control blight. 

Two types of blight are known to attack plants—early and late blight. Early blight causes dark spots on leaves that have a yellow ring around them. The spots will dry and fall off leaves, creating holes. Late blight results in spots on leaves and stems and can lead to wilting. Blight is caused by the spreading of fungal spores via wind or water. Blight is common in warm and humid environments. Rainfall can increase the likelihood of blight developing and spreading. Tomatoes and potatoes are very susceptible to blight, but this disease can affect a variety of plants. 

Inspect Plants Regularly: It’s important to regularly check your plants for signs of blight. Catching it early will make it easier to control the disease and limit the damage to your plants. You’ll also want to inspect plants before bringing them home and introducing them to your garden.

Set Your Plants Up for Success: Making sure your plants receive enough water and sunlight can help to prevent diseases and pests. Healthy plants are less susceptible to the diseases. Know what your plants need and plan accordingly. When watering your plants, water at the base of the plant to keep leaves dry and minimize splashing.

Add Mulch to Your Garden: Mulch or woodchips can be a great addition to your garden. Adding mulch around your plants can help to prevent fungal spores from transferring to your plants.

Plant in the Right Spot: When planning your garden, you’ll want to allow for space between your plants. Creating this space will increase airflow, which will help to decrease humidity and allow plants to dry quicker. You’ll also want to rotate where you plant every year. Rotating your plants can help to protect them from left behind fungal spores, especially if they are a preferred host plant.

Remove Infested Leaves: If you notice blight on your plants, you’ll want to prune infected leaves. This will help to prevent the disease from spreading. Be careful to not shake the leaves to keep spores from transferring to new leaves and plants. Disinfect your garden tools when you’re done to ensure the disease doesn’t spread.  

Treating your plants with a spray labeled for fungal diseases can help to protect your plants from blight. Maggie’s Farm offers two products that can help to prevent and control blight.

Plant-Based Insecticide Sprays
Our 3-in-1 Garden Spray and our Vegetable Garden Insect & Disease Control spray are labeled to prevent and control blight. Our 3-in-1 Garden Spray is formulated using plant oils as the active ingredients. It is a fungicide, insecticide, and miticide that can be used on indoor and outdoor plants including flowers, shrubs, vegetables, herbs and other edible plants, and ornamental plants. Our Vegetable Garden Insect & Disease Control spray is formulated with pyrethrins. It can be applied to vegetables, ornamental trees and shrubs, flowers, and fruit or nut trees in your garden, home greenhouse, and on indoor plants.

Application Tips
When treating your plants, don’t spray in the heat of the day. Instead, spray early in the morning or in the evening. For best results, apply as a protective spray early in the season before blight and other diseases are noticed. You will want to thoroughly spray the entire plant, including the underside of leaves. Apply our 3-in-1 Garden Spray so that the product runs off the tips of the leaves. It can be applied every 7–10 days and can be used up to the day of harvest. Our Vegetable Garden Insect & Disease Control spray shouldn’t be applied to the point of runoff or drip. Don’t apply if temperatures are expected to be over 90° F. This product can be applied every 7–10 days and can be used up to the day before harvest.

It is always best to test treat a small inconspicuous area of the plant first before applying to the entire plant. 

Blight and other fungal diseases can affect the health of your plants, which is why it’s important to take steps to protect them. Implementing preventative measures and using the right products can help to control this fungal disease.