What Is Wrong With My Mustard?

Are there any dark spots on leaves that turn brown to gray, lesions may be round or angular and may possess a purple-black margin?

Are the roots enlarged and clublike, plants are stunted with yellowish leaves that wilt during the day?

Do the leaves have pale areas on upper surfaces and "downy" patches underneath?

Are the leaves covered with white powdery growth?

Are there any irregular, necrotic gray lesions on leaves, and white-gray lesions on stems?

Are there any small, necrotic, brown spots on leaf tips or margins that mature to light gray or white with the original dark spot in center?

Are there any white masses of fungal spores on the underside of leaves, green blisters on the leaves which turn white?

Are there any irregularly shaped dull yellow areas along leaf margins which expand to leaf midrib and create a characteristic "V-shaped" lesion?

Are the leaves curled and yellow?

These symptoms indicate Alternaria leaf spot. Warm, wet conditions favor this fungal disease. Spray infected plants with copper and/or sulfur to prevent further disease development. Plant only pathogen-free seed from a reputable nursery.

Enlarged and clublike roots are most likely caused by fungal disease - Club root. Remove and destroy any infected plants. Applying lime to the soil can reduce fungus sporulation.

Pale areas on upper surfaces of the leaves and "downy" patches underneath are caused by Downy mildew. This fungus spreads quickly during cool, wet nights and warm, humid days. Leaves will wilt and die. Remove and destroy all affected plant parts and encourage good air circulation around plants by thining them. Water plants early in the morning to make sure they dry before nightfall.

White, powdery patches on the leaves are caused by a fungal disease Powdery mildew. Powdery mildew usually appears in damp places. Encourage good air circulation around the affected plants by thining them and any surrounding plants. Water plants from bellow to keep foliage dry. Any affected leaves should be cut off and removed. Any commercial fungicidal spray will protect your plant from further infections.

Sclerotinia stem rot (white mold) is a fungal disease that causes these symptoms. Wet weather conditions favor this disease. The disease is usually introduced to non-infected areas by infected seed. Plant only certified seed. If the disease is known to present rotate crops with non-hosts such as cereals.

These symptoms indicate a White leaf spot. Warm, wet conditions favor this fungal disease. Spray infected plants with copper and/or sulfur to prevent further disease development.

Fungal disease White rust causes these symptoms. Disease development is favored by cool weather and periods of extended rainfall. Destroy infected leaves or plants. Remove weeds and any debris from around plants. Avoid the use of sprinklers for irrigation. Apply appropriate fungicide if the disease becomes a problem.

These symptoms indicate a bacterial disease - Black rot. Prevent this disease by providing well-drained soil and by using a 2-year rotation. Plant resistant varieties. Control cruciferous weed species which may act as a reservoir for bacteria. Plant pathogen-free seed.

Distorted, curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted, and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.

If there are tiny holes in leaves they are caused by Flea beetles. These tiny, black, brown, or bronze beetles hop when disturbed. Larvae are small and white, feed mostly on the undersides of leaves. Prevent problems by covering young plants with row cover. Control severe infestations by spraying or dusting plants with pyrethrin.