FREE - Organic Natural Disease Control

Organic gardening practices produce plants that are naturally disease resistant. Sometimes though, even the strongest plants will be affected by disease. Fortunately, natural disease control methods are effective in weed and insect control.

VEGETABLE	DISEASES
Asparagus	Leaf Spot
Beans	Rust, Virus
Beets	Leaf Spot
Cabbage Family	Mildew, Black Rot
Cantaloupe	Mildew, Leaf Spot
Carrots	Leaf Spot
Celery	Leaf Spot
Corn	Corn Smut
Cucumber	Mildew, Leaf Spot
Eggplant	Nematode, Anthracnose
Lettuce	Mildew, Botrytis
Mustard	Mildew
Okra	Root Rot
Onions	Mildew
Peas	Mildew
Peppers	Leaf Spot
Potatoes	Blight
Pumpkin	Mildew
Spinach	Rust, Mold, Fusarium Wilt
Squash	Rot, Virus
Tomatoes	Blight
Turnips	Rust, Mildew
Watermelon	Leaf Spot, Fusarium Wilt

You can use Google search to find pictures and more info on the individual diseases. Also, follow the Soil Preparation and Crop Rotation links at the top of this page for complete information on Control methods.

DISEASE	DESCRIPTION	CONTROL METHOD
Black Rot	Fungal disease characterized by V-shaped yellow lesions and black discoloration of the leaf veins.	Pasteurize the soil. Rotate crops.
Blight	Fungal disease that causes sudden spotting or wilting of the foliage.	Pasteurize the soil. Rotate crops. Add humus to the soil.
Botrytis	Fungal disease that starts in the leaves touching the ground with a slimy rot that spreads into the center of the plant.	Pasteurize the soil. Rotate crops.
Corn smut	Fungal disease characterized by large fleshy galls on the plant aboveground.	Remove and destroy smut before galls open and release spores. Pasteurize soil. Rotate crops.
Fusarium Wilt	Soil-borne fungus that causes leaves to wilt.	Pasteurize the soil. Rotate crops.
Leaf spot	Fungal disease that causes spots on leaves.	Pasteurize the soil. Rotate crops.
Mildew	Either a white coating on the plant or dark spots on the leaf tops with gray mold underneath.	Pasteurize the soil. Rotate crops.
Root rot	Soil-borne fungus characterized by rotten roots that cause the plant to die suddenly.	Pasteurize the soil. Rotate crops.
Ground Rot	Disease that causes fruit in contact with the soil to rot.	Mulch around plants to keep fruit off the soil.
Rust	Fungal disease that produces reddish, dusty spots on the lower surface of the leaves.	Pasteurize the soil. Rotate crops.
Virus	Many types of virus attack plants causing foliage to wilt and plant to die.	Pasteurize the soil. Rotate crops.

PRACTICE	DESCRIPTION
Green Manure	Plow under a green crop (called green manure) such as wheat or rye. Green manure enriches the soil and helps eliminate soil-borne diseases. Crop can be planted after decay is complete, which is about 6 weeks in the summer.
Rotation	Crops are rotated to prevent disease. Soil-borne diseases are controlled by not planting crops in the same area in succeeding years. See Crop Rotation.
Sanitation	At the end of the growing season, clear away old plants and either compost or shred them for mulching. Diseased plants must be burned or composted to prevent further disease. See Garden Sanitation on the Soil Preparation page.
Soil Pasteurization	Soil Pasteurization rids the soil of garden pests such as bacteria, fungus, insects, nematodes, and weeds. Soil Pasteurization must be done during several weeks of hot weather. See Soil Pasteurization on the Soil Preparation page.

NATURAL DISEASE CONTROL