Pests and Diseases

Pests and diseases can make a mess of a well-maintained and beautiful garden. It’s essential to do everything you can to keep them under control. Use Penn State Extension’s extensive resources and learn about recommendations for managing garden pests and diseases, including webworms, beetles, weevils, mites, slugs, spotted lanternflies, leafminers, spiders, and aphids. Find tips on scale, root rot, viruses, and integrated pest management.

Common Garden Pests and Diseases

You might encounter a range of problems in your home garden, many of which will result from pests or diseases. Scouting your garden and recognizing the root cause of a problem means you’ll treat it more effectively.

If your cucurbits are wilting, it could be because of several diseases, including bacterial wilt, Fusarium wilt, and cucurbit yellow vine wilt. However, it could be abiotic stresses such as waterlogged soil.

The reason for there being no fruit on your trees could also be pests or diseases. On the other hand, it could be over-pruning or over-fertilization that is the cause.

Browning leaves and leaves with a pale green color in orchardgrass and timothy may indicate a fungal infection.

Pests and diseases can also affect the plants in your home. Houseplant damage can result from pests such as aphids, mealybugs, mites, scale, thrips, and whiteflies. Common diseases include anthracnose, leaf spots, and powdery mildew, as well as root and stem rots.

One insect pest that is now considered an invasive insect is the spotted lanternfly. Learn how to identify this pest, and you can help contain its spread.

Identifying Garden Pests and Diseases

There are lots of things that can make your plants unwell. Identifying the root cause and recognizing symptoms of different diseases means you’re able to make an informed treatment decision. If you want a low maintenance garden, aim to restrict your use of key plants, as these are the ones that frequently have diseases.

Common pests include:

• Bulb crops: Onion thrips, onion maggots.
• Leafy vegetables: Leafminers, aphids, cabbage worms.
• Sweet corn: Corn earworms, European corn borers, fall armyworm, sap beetles, flea beetles.
• Fruiting vegetables: Broad mites can cause severe damage to tomatoes and peppers.
• Tomatoes: The tobacco hornworm can devour sizeable portions of tomato plantings. Another problem for tomato growers is tomato-potato late blight.
• Strawberries: Anthracnose is caused by different species in the genus Colletotrichum
• Grapes: Powdery mildew symptoms include cupping of leaves, scorched or brown leaves, and white, powdery patches on the upper surface of the leaves.
• Apples and pears: Mucor rot is a fungal disease that is a problem in postharvest storage. Pears can also suffer from stony pit, which is a destructive virus that leaves the fruit looking unsightly and unmarketable.
• Potatoes: A common problem for potato growers is early blight.
• Trees and shrubs: A common disease with more than 75 species of trees and shrubs is fire blight.

Pesticides and Integrated Pest Management in the Home Garden

Traditionally, home gardeners would use pesticides to manage pests in their gardens and keep the landscape healthy. Commercial growers have used Integrated Pest Management for many years. More and more amateur and home gardeners are now using home, lawn, and garden integrated pest management techniques. It is a management method that seeks to limit or suppress pest populations by using various compatible tactics.

Integrated pest management tactics minimize potential harmful effects on the environment and human health. There is still a place for synthetic, natural, and organic pesticides, but generally, only as a last resort. A crucial part of IPM is scouting for common diseases, mite pests, and beneficials.

Preferred pest management tactics include encouraging beneficial insects into the garden, biological control, planting cover crops, and monitoring insect pests.