Leaf Spot Management Guide

Plant diseases can cause problems for your plants, which is why it’s important to know what you’re up against. Leaf spot is a common garden disease that not only affects the appearance of plants but can also weaken them. We’ve gathered information to help you control and prevent leaf spot in your garden.  

Leaf spot can be caused by fungi or bacteria and spreads via water or wind. The disease causes spots to form on plant leaves. These spots can vary in size, color, and shape, but brown or black spots are the most common. As the disease progresses, the spots can spread, forming patches. This disease can weaken plants, causing leaves to turn yellow or fall. Leaf spot can infect a variety of plants including shrubs, houseplants, vegetables, and trees. It thrives when water and warm air are present. 

Inspect Plants Regularly: Catching leaf spot early will make it easier to control the disease and prevent it from spreading. Take time to check your plants for signs of leaf spot regularly. You’ll also want to inspect new plants before buying them and bringing them home.

Set Your Plants Up for Success: Keeping your plants healthy will make them less susceptible to diseases and pests. Make sure to give your plants the right amount of water. Watering too much or too little can cause problems. Place your plants in areas where they will receive the sunlight they need. Each plant has their own needs, so research before planting to ensure you’re good to go.

Water Plants Carefully: Leaf spot does well in damp conditions, so it’s important to avoid moisture build-up. Watering at the base of your plants will help to limit how much moisture is present on leaves. It can also help to water your plants early in the day to allow the leaves time to dry in the sun.

Create Space Between Your Plants: Creating space between your plants can help to prevent leaf spot. This will improve the airflow, which will help to keep things dry. It can help to prevent the disease from spreading to other plants too.

Remove Infected Leaves: If your plants are dealing with leaf spot, you’ll want to prune them. Removing infested leaves will help keep the disease from spreading. After pruning your plants, you’ll want to discard the infested leaves. Make sure to clean your gardening tools before using them on your other plants. 

Plants battling leaf spot can be treated with a plant-based insecticide spray. Maggie’s Farm offers two products that can help to control and prevent leaf spot.

Plant-Based Insecticide Sprays
Our 3-in-1 Garden Spray and our Vegetable Garden Insect & Disease Control spray are labeled to prevent and control leaf spot. Our 3-in-1 Garden Spray is formulated using plant oils as the active ingredients. It can be used on a variety of plants including roses, flowers, houseplants, vegetables, shrubs, herbs and edible plants, and ornamental plants. Our Vegetable Garden Insect & Disease Control spray is formulated using pyrethrins and sulfur. It can be applied to vegetables, flowers, roses, ornamental trees and shrubs, and fruit and nut trees found in your garden and home greenhouse. It can also be used on houseplants.

Application Tips
Our garden products shouldn’t be applied during the heat of the day. It’s best to spray your plants early in the morning or in the evening. You will want to apply as a protective spray early in the season before diseases are noticed. Spray all parts of the plant. Apply our 3-in-1 Garden Spray so that the solution runs off the tips of the leaves. It can be applied every 7–10 days or after rain and may be used up to the day of harvest. When using our Vegetable Garden Insect & Disease Control spray, you don’t want to wet plants to the point of runoff or drip. If temperatures are expected to be over 90° F, avoid spraying your plants. Applications can be done every 7–10 days. You can use this product up until the day before harvest.

We recommend test treating a small inconspicuous area of the plant first before applying to the entire plant

It’s important to take steps to protect your plants from leaf spot and other fungal diseases. Implementing preventative measures and using the right products can help to keep leaf spot from harming your plants.