Leaf spot is the common name for many fungi and bacteria that have a similar effect in plants. Trees with leaf spot typically do not require treatment, but leaf spot can damage plants, especially new, less established plants.
Read below for more information on how to treat plants with leaf spot and prevent leaf spot in the future. Leaf spot in grass is identified and treated differently. If you believe you have leaf spot in your grass, read our leaf spot in grass guide for more information.
What Does Leaf Spot Look Like?
Leaf spot is most commonly identified on plants by small spots on leaves. The spots will vary in size and color depending on the plant and the strain of the disease, but commonly spots can be dark brown, black, tan, or yellow.
Spots are usually consistent in size at first, but as the disease spreads these spots can morph together to form large patches.
What Causes Leaf Spot?
Leaf spot can be a bacterial or fungal disease. The bacteria or fungi can be found on dead leaves or twigs on the ground or soil. When temperatures warm and weather is wet, spores of the fungi or bacteria can blow onto living plants. The wet, warm plants absorb the spores and become infected with the disease.
What Plants are Susceptible to Leaf Spot?
As there are many different types of leaf spot, leaf spot can be found in many different plants. Many fruit and vegetables can have leaf spot, including cabbage, broccoli, kale, cherries, almonds, apricots, peaches, plumbs, peppers, and tomatoes. Leaf spot can also be found on flowering plants, foliage, and even indoor potted plants.
How to Get Rid of Leaf Spot
Leaf spot is typically not very harmful to older, established plants unless the disease reoccurs yearly or more frequently. In younger, less established plants, leaf spot can spread quickly and cause the plant to wilt or die.
If you see leaf spot in your plant, you can treat with a fungicide labeled for leaf spot. There are also natural products designed to treat leaf spot. Look for products with a high sulfur or copper octanate content.
Read the label of your fungicide to determine the mixing rate and if the fungicide will be applied to just the roots and soil of the plant or if the plant leaves will also need to be treated.
If your indoor potted plant has leaf spot, isolate the plant from other potted plants before treatment to prevent the spread of the disease. Look for a fungicide or natural treatment product labeled for indoor use.
How to Prevent Leaf Spot
It is not always possible to prevent leaf spot in plants as the disease spreads during wet weather and wind. Fungal spores from a neighbor's lawn could blow into your lawn and infect your plants.
The following methods will prevent leaf spot as much as possible and keep your plants healthy.
- Remove leaves and twigs that have been infected by leaf spot from the plant.
- Remove dead leaves and twigs from the soil and turf around plants.
- Keep plants dry. Water in the early morning so the sun has time to dry plants before night.
- Do not overwater plants. Overwatering leaves plants wet for longer periods of time, allowing the disease to spread.
- Keep plants healthy so they are better able to fight disease. Early intervention of plants that are wilting or appear dry will help them survive leaf spot if infected.
- Water indoor plants at the roots. Do not mist leaves, especially if the plants are kept in a warm, humid room.
If you have any questions about leaf spot in plants and how to treat it, give our customer service team a call at 866-581-7378 or email firstname.lastname@example.org. For information about leaf spot in grass, read our leaf spot on turf guide.