Why Hasn't My Rutabaga Developed Well?

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?

Do the leaves have a small circular or irregularly shaped dry spots which are gray to straw in color?

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

Are there any angular or circular green to gray spots with brown borders on leaves?

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

Are the leaves distorted and yellow, clusters of small insects are present?

Are there any scars and feeding tunnels on the surface of rutabaga, root damage may be extensive?

Are the seedlings dying, stems are girdled, yellow-brown larvae can be found in the soil around the stem?

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.

These symptoms indicate a fungal disease - Anthracnose. Keep plants dry when watering to prevent spread. Spray plants with copper if you have had problems in the past. Apply copper fungicide early in the season.

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.

These symptoms indicate a fungal disease - Cercospora leaf spot. This fungal disease only occurs in very warm climates. Spots develop a “frog-eye” appearance with light centers and dark edges. Spray plants with copper as soon as symptoms appear to prevent further symptom development.

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.

Distorted, yellow 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.

Root maggots are usual pests of young rutabagas. Check for white or white-yellow larvae inside the soil. Keep garden clean of debris and plant residue. Keep garden weed-free. Use cardboard collars around seedlings. Use floating row covers to exclude flies and moths from laying eggs in the soil.

Yellow to reddish-brown, slender, tough-bodied, segmented worms feeding on roots are wireworms. Adults are dark-colored, elongated click beetles. Apply parasitic nematodes to the soil before planting to control them.

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.