Why Does My Spinach Look Unhealthy?

Are the leaves yellow and are the plants stunted?

Are the plants wilted?

Are the leaves yellow and deformed?

Do you see any small insects on the undersides of the leaves?

Are only the young leaves yellow, deformed and stunted?

Do the leaves have pale yellow patches on their upper surfaces?

Has a grayish mold developed on the undersides of the leaves?

Do the leaves have brown spots or water-soaked spots on them?

Do the leaves have light-colored tunnels or blotches in them?

Do the leaves have small holes in them?

Do the leaves have large, ragged holes in them?

Your spinach may be suffering from nitrogen deficiency or waterlogged soil. Spray plants and drench roots with compost tea or fish­ meal tea to encourage the production of dark green leaves. Prevent future problems by choosing well-drained sites, adding organic matter to the soil to increase fertility and improve drainage, and planting in raised beds.

Wilted plants have a condition called Fusarium wilt. Destroy infected plants. This fungal disease thrives in warm (70°-80°F) soil, so avoid problems by growing spinach while the soil is cool in spring or fall.

The insects are aphids. These tiny insects can vary in color (green, pink, black, gray or completely white). They cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and flowers drop from the plant. You can control these pests by washing them off the plant with water spray. Insecticidal soap should be used only with severe infestations.

Your plant might be suffering from Curly top virus. Viral diseases are incurable. Destroy all infected plants. Control leafhoppers as they are most likely carriers of the curly top virus.

If older leaves are also mottled, the plant is suffering from Mosaic virus. Viral diseases are incurable. Destroy all infected plants. Control aphids as they are most likely the carriers of the mosaic virus. Mosaic-tolerant cultivars are ‘Indian Summer,' ‘Melody,' and ‘Winter Bloomsdale.'

These patches are caused by Downy mildew. Control this fungal disease by spraying plants with a baking-soda-and-soap spray (1 teaspoon baking soda. 1 teaspoon liquid dish soap, 1-quart water) or copper. Prevent future problems by thinning plants to increase air circulation and by planting tolerant cultivars like ‘Crystal Savoy,' ‘Fall Green,' ‘Gladiator,' ‘Indian Summer.'

If there are white blisters on the undersides of the leaves the culprit is a fungal disease White rust. Destroy infected leaves or plants. Prevent problems by thinning plants to increase air circulation and by planting tolerant cultivars such as ‘Fall Green*.

Your spinach may be suffering from Anthracnose or some other fungal leaf spot. Spots may grow rapidly, especially in wet weather. Destroy infected leaves or plants. Spray plants with sulfur to prevent the disease from spreading, especially if the weather is wet. Prevent future problems by thinning plants to provide good air circulation.

These symptoms are usually caused by Leafminers. These tiny pale green larvae feed between the upper and lower surfaces of the leaves. Prune off and destroy all infested leaves. Remove debris in the fall as it might contain overwintering leafminers. Introducing parasitic wasps is a very effective method of controlling leafminers.

Small holes in spinach leaves 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.

Various caterpillars will feed on spinach. Handpick, or spray plants with BTK if caterpillars are feeding, or protect plants with row cover.

If the spinach plant sends up a flower stalk (bolting) the probable cause is extreme temperatures. Discard bolted plants. Prevent future problems by covering the plants with row cover until temperatures are stable.