Cucumbers
Cucumis sativus
Refreshing summer vegetable that grows on vines
Growing Conditions
- Full sun (6-8 hours daily)
- Well-draining, fertile soil
- Consistent moisture
- Warm temperatures
- Support structure for climbing
Common Problems
Powdery Mildew
Cause:
Fungal infection favored by humid conditions
Solution:
Improve air circulation, apply fungicides if needed
Organic Treatments:
Sulfur or potassium bicarbonate
Synthetic Treatments:
None - fungal issue
Visual Description:
White, powdery coating appears on leaves, starting as small circular spots that expand to cover entire leaf surfaces. The powder can appear on both sides of leaves and stems. Affected leaves may turn yellow, then brown, and die prematurely. Disease spreads rapidly in humid conditions with poor air circulation. Severe infections can defoliate plants and reduce yield.
Bitter Fruit
Cause:
Environmental stress or variety
Solution:
Consistent watering, proper fertilization
Organic Treatments:
Balanced organic fertilizer
Synthetic Treatments:
Balanced NPK fertilizer (10-10-10)
Visual Description:
Cucumbers develop an intense bitter taste, particularly near the stem end or throughout the fruit. The bitterness is caused by compounds called cucurbitacins. Externally, the cucumbers may appear normal, but upon tasting, the bitterness is immediately noticeable. The condition is more common in the outer portions of the fruit near the skin.
Angular Leaf Spot
Cause:
Bacterial infection
Solution:
Remove infected leaves, avoid overhead watering
Organic Treatments:
Copper-based organic fungicide
Synthetic Treatments:
Copper-based bactericide
Visual Description:
Small, water-soaked spots appear on leaves, bounded by leaf veins giving them an angular appearance. Spots turn tan to brown and may have yellow halos. The centers of older spots may fall out, creating a tattered appearance. On fruit, small, circular water-soaked spots may develop, which can provide entry points for other pathogens.
Cucumber Beetles
Cause:
Striped or spotted cucumber beetles
Solution:
Row covers, trap crops, insecticides
Visual Description:
Adult beetles (about 1/4 inch long) are yellow-green with black stripes or spots. They feed on leaves, flowers, and fruit, leaving small holes or scarred areas. Young plants can be killed by heavy feeding. The beetles also spread bacterial wilt disease, causing plants to suddenly wilt and die. Larvae feed on roots underground.
Blossom End Rot
Cause:
Calcium deficiency or irregular watering
Solution:
Maintain consistent moisture, add calcium
Organic Treatments:
Crushed eggshells or calcium spray
Synthetic Treatments:
Calcium nitrate (15.5-0-0 + 19% Ca)
Visual Description:
Dark, water-soaked areas develop at the blossom end of young fruits. These areas enlarge and become sunken, brown to black, and leathery. The condition typically appears when fruits are one-third to half grown. While the rest of the cucumber may appear normal, the damaged end is inedible and can lead to fruit rot.
Mosaic Virus
Cause:
Viral infection spread by aphids
Solution:
Remove infected plants, control aphids
Organic Treatments:
None - viral issue
Synthetic Treatments:
None - viral issue
Visual Description:
Leaves show mottled patterns of light and dark green, often with distorted, wrinkled, or bubbled areas. New growth may be stunted and yellowed. Fruits can be mottled, warted, or misshapen. The virus causes overall plant stunting and reduced yields. Once infected, plants cannot be cured and serve as sources of infection for other plants.
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