Broccoli
Brassica oleracea var. italica
Nutrient-rich cruciferous vegetable known for its dense, edible flower heads
Growing Conditions
- Full sun (6 hours minimum)
- Rich, well-draining soil
- Cool temperatures
- Regular watering
- Good air circulation
Common Problems
Aphids
Cause:
Small soft-bodied insects infesting plants
Solution:
Use insecticidal soap, encourage beneficial insects
Organic Treatments:
None - pest issue
Synthetic Treatments:
None - pest issue
Visual Description:
Small (1/8 inch) pear-shaped insects clustering on leaves and heads, especially in new growth. Colors range from green to gray or black. Leaves may become distorted or curled. Sticky honeydew residue often present, sometimes with black sooty mold growing on it. Heavy infestations can cause stunted growth and reduced head quality.
Black Rot
Cause:
Bacterial infection (Xanthomonas campestris)
Solution:
Remove infected plants, improve air circulation
Organic Treatments:
None - bacterial issue
Synthetic Treatments:
None - bacterial issue
Visual Description:
Distinctive V-shaped yellow to brown lesions along leaf margins, with blackened veins running through them. As the disease progresses, affected leaves may wilt, turn brown, and drop prematurely. Stems may show dark discoloration, and the entire plant can become stunted. In severe cases, the characteristic V-shaped lesions may appear on multiple leaves, giving the plant a scorched appearance.
Cabbage Worms
Cause:
Caterpillar pests feeding on leaves
Solution:
Hand-pick caterpillars, use Bt spray
Organic Treatments:
None - pest issue
Synthetic Treatments:
None - pest issue
Visual Description:
Velvety green caterpillars that blend with leaves, creating irregular holes starting from leaf edges. Small dark green droppings present on leaves. White butterflies (adults) often seen flying around plants. Young leaves may be completely skeletonized, leaving only veins. Damage can extend to developing heads, reducing marketability.
Clubroot
Cause:
Soil-borne fungus (Plasmodiophora brassicae)
Solution:
Maintain soil pH above 7.0, improve drainage
Organic Treatments:
None - fungal issue
Synthetic Treatments:
None - fungal issue
Visual Description:
Roots develop large, irregular swellings or clubs, distorting their normal shape. Above ground, plants show stunted growth and wilting, especially during warm days. Leaves may yellow or purple, and heads remain small. The characteristic root galls can vary from small nodules to massive growths encompassing the entire root system.
Downy Mildew
Cause:
Fungal infection in cool, humid conditions
Solution:
Improve air circulation, apply fungicides
Organic Treatments:
Synthetic Treatments:
Systemic fungicide
Visual Description:
Yellow to light green patches appear on upper leaf surfaces, with gray-white fuzzy growth developing on the undersides, particularly visible in morning hours. Lesions are typically angular, bounded by leaf veins. As the disease progresses, affected areas may turn brown and die. The characteristic downy growth is most prominent during periods of high humidity.
Head Rot
Cause:
Bacterial infection in wet conditions
Solution:
Improve drainage, avoid overhead watering
Organic Treatments:
None - bacterial issue
Synthetic Treatments:
None - bacterial issue
Visual Description:
Initial water-soaked lesions on florets that progress to brown, soft tissue. Affected areas develop a distinctive foul odor. Under wet conditions, bacterial ooze may be present. The rot can spread rapidly through the head, causing complete collapse of the tissue. Early symptoms often appear as dark, water-soaked spots that quickly enlarge.
Hollow Stem
Cause:
Physiological disorder, often related to boron deficiency
Solution:
Balance nutrients, especially boron levels
Organic Treatments:
Borax or seaweed extract
Synthetic Treatments:
Boron supplement
Visual Description:
Stems become hollow and may show brown discoloration inside. The hollow area can extend into the head, affecting quality. Plants may appear normal externally but show internal browning when cut. In severe cases, the stem may crack or become deformed. The condition is more common in rapidly growing plants or during periods of moisture stress.
Nutrient Deficiency
Cause:
Various mineral deficiencies in soil
Solution:
Soil testing, appropriate amendments
Organic Treatments:
Compost, fish emulsion
Synthetic Treatments:
Complete fertilizer (10-10-10)
Visual Description:
Symptoms vary by nutrient but often include yellowing leaves, stunted growth, or purpling. Newer leaves may be small or deformed. Head development may be poor or irregular. Plants generally appear weak and may show stress symptoms like wilting during the day.
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