There are many diseases that can threaten your garden’s safety. Every good gardener must see to it that aside from giving his plants water, sun, and nutrients, diseases are kept at bay. Here are some of the most common types of plant diseases to look out for and how to treat them.
Leaves or branches that suddenly wither or brown and stop growing is a sign of a type of blight. It is bacterial disease that causes chlorosis or insufficient production of chlorophyll – causing the plant to die. The common types of blight include fire blight, alternaria blight or early blight, and phytophthora blight or late blight. Blights are common during humid weather or after a period of heavy rainfall. Once you spot these black-brown spots on your plants and leave begin to turn yellow, immediately remove and destroy affected leaves. They can be treated with fungicides and biofungicides but quickly become resistant to it-so treat fast and treat hard, ensuring all affected plants are treated. Ensure plants have good drainage and prevent overhead watering. Mulching with black plastic or rubber mulch prevents the fungus from spreading onto the leaves. You can also opt to use disease-resistant hybrids especially if blights are common in your area.
Can be caused by bacteria, fungi or other organisms, cankers usually form on woody stems, causing them to wither and die. While some plants with cankers look similar to blight damage, but some cankers ooze, may look sunken and leaves lesions on tree barks. Man-made or natural wounds are the usual entry point for many fungal cankers and usually does not manifest until the plant or tree is under stress. There are cankers that aggressively affect some plants and have no cure. In cases like these, the entire plant must be removed to prevent nearby plants from being infected. To prevent cankers, use proper pruning techniques to only create small wounds so they can heal quickly. Do not prune during wet seasons as this is when cankers and other fungi are most active. Promote plant health and vigor by watering and properly, moderate fertilizing, and mulching- this way your plants have the ability to protect themselves from disease.
These are diseases that decay part dog the plant. The rot can affect roots, stems, leaves, and even fruits – leaving them soft and slimy or hard and dry. They can be caused by various types of bacteria or fungi. The best defense against rots are ensuring good drainage. Make sure the roots are completely dry before watering again. For already infected areas, make sure to remove and dispose them and apply compost tea or add beneficial bacteria to your soil.
A powdery coating or a rust-colored coating is one of the easiest ways to identify plant rusts. These are kinds of fungi that attacks healthy and vigorous plants unlike other plant diseases that take advantage of weak plants. Rusts will take advantage of new sprouts, leaves and tender parts of a plant. Severe infection of rusts will cause stunted growth and yellowed or discolored leaves. For small infections, areas where pustules (orange, yellow, brown, black, or white spore producing structures) are visible must be removed and disposed. Applying neem oil can kill spores on the leaves and is a good organic alternative to fungicides.
Leaves wilt when they are not properly hydrated. In many cases, a small amount of wilt in between watering is healthy and prevents root rots. But when wilts continue to show even after replenishing your plant supply, your garden may be infected with fungi or bacteria that prevents your plant’s water conducting system from functioning properly. Some types of wilt like the verticillium wilt are very destructive and can stay in the soil for a long time. In many cases just removing infected areas may not work and it is better to completely remove the infected plat including the soil to prevent further damage to other plants. Do not use previously infected soil or include infected leaves to compost.
There are many diseases out there that may affect your plants. Your best defense is to make sure they are healthy so they have a chance to fight illnesses. Proper watering, good drainage, adequate sunlight, consistent pruning, mulching, and fertilizing at the right time will go a long way. It also helps to look out for certain disease-resistant crops to lower their chances of getting infected