Why Haven't My Brussel Sprouts Developed Well?

Do the leaves have colored spots on them?

Are the spots V-shaped, yellow and appearing on margins of the leaves?

Are the spots yellow-brown and concentrically ringed?

Are the spots pale and is there a white growth on undersides of the leaves?

Are the leaf spots white-bronze?

Did the whole leaves change color?

Have the leaves of the Brussel sprouts transplants turned purple?

Have the leaves turned yellow and are the whole plants stunted?

Have the leaves turned yellow, the plant is stunted and wilts on bright, hot days?

Are the roots enlarged and clublike?

Are the roots covered with irregularly shaped galls?

Have the leaves turned yellow, the plant is stunted and the stems are twisted?

Do the leaves have holes in them?

Have the tips of the leaves turned brown?

Yellow, V-shaped spots most likely indicate the bacterial disease - Black rot. Infected leaves will die and drop off. Destroy infected plants. Spray copper if the weather is wet and if you had problems with black rot in the past.

Yellow-brown and concentrically ringed spots are caused by fungal disease - Alternaria blight. This disease attacks lower leaves first. As the disease progresses leaves and eventually the whole plant will die. Spray plants with copper at the first signs of disease.

White, cottony growths on undersides of the leaves are caused by fungal disease - Downy mildew. Control by spraying plants with a baking-soda-and-soap spray (1 teaspoon baking soda. 1 teaspoon liquid dish soap, 1-quart water) or copper.

White-bronze spots on the leaves are caused by thrips. Severely infected plant parts should be removed and destroyed. Control thrips by introducing lady beetles or lacewings, their natural predators. Insecticidal soap helps in severe infestations.

Brown to gray spots on the Brussel sprouts leaves may indicate the fungal disease - Black leg. Other symptoms include stem with sunken areas that enlarge over time. Dead leaves will stay attached to the plant. Spray plants, especially the stems, with copper at the first sign of disease.

Purple color on Brussel sprouts transplants leaves indicates phosphorus deficiency. Phosphorus is not readily available in cool spring soils. Spray plants with seaweed extract to correct.

Yellow leaves and stunted plant growth most often indicate nitrogen deficiency. Spray plants and drench roots with fish emulsion to correct. You can also use any nitrogen-rich fertilizer for fast results.

Enlarged and clublike roots are most likely caused by fungal disease - Club root. Remove and destroy any infected plants. Keep the pH of the soil 7.2 or above to prevent club root fungi activity.

Brussel sprout roots covered with irregularly shaped galls are caused by root-knot nematodes. Destroy severely infested plants. Solarizing the soil should reduce the number of nematodes in the ground. Planting winter wheat cover crop will also help in prevention.

If the roots are riddled with slimy, winding tunnels, the Brussel sprouts are infested by cabbage maggots. These larvae feed on Brussel sprouts roots and transfer bacterial and fungal diseases. Remove and destroy infected plants. Solarizing the soil will help reduce maggot populations in problem areas.

The likely cause for these symptoms is the fungal disease - Fusarium yellows. There is no cure for Fusarium yellows, so infected plants should be destroyed as soon as possible.

Curled yellow leaves are often caused bu aphids. These tiny insects cluster under leaves where they feed on plant sap. You can control them by washing them off the plants with water spray.

If the holes are small they are caused by Striped flea beetles; large, ragged holes are caused by caterpillars. Protect young plants with row' cover until they have at least 6 leaves. Apply a BTK spray as soon as active caterpillars or feeding is observed.

Excessive heat or calcium deficiency may have caused browning of the Brussel sprouts leaf tips. Keep soil moisture constant and side-dress plants with compost to provide balanced nutrition.

Poor growing conditions could have caused Brussel sprouts to develop poorly. You should plant Brussel sprouts in full sun in a site with fertile, well-drained soil and a pH between 5.5 and 6.8. Keep soil evenly moist at all times.