SYMPTOMS
Gray-white to yellow pinpricks (stipples) appear on both sides of the leaves. Many stipples form in lines parallel to leaf veins. Look for delicate webs on leaves.
DIAGNOSIS
mites: two-spotted spider mite (Tetranychus urticae), carmine spider mite (Tetranychus cinnabarinus), hemp russet mite (Aculops cannabicola)
SOLUTIONS
• Sanitize
• Use beneficial insects
• Use beneficial mites
• Use beneficial fungi
• Use kaolin
• Use insecticidal soap
• Use neem
• Use horticultural oil
• Manage humidity
SYMPTOMS
Silver-white or yellowish speckles and streaks appear on the undersides of leaves. Black specks that look like ground pepper cover plants. Leaves curl up. The plant wilts turns brown, and dies.
DIAGNOSIS
thrips: onion or tobacco thrips (Thrips tabaci), greenhouse thrips (Heliothrips haemorrhoidalis), marijuana thrips (Oxythrips cannabis), Indian bean thrips (Caliothrips indices), western flower thrips (Frankliniella occidentalis)
SOLUTIONS
• Sanitize
• Use screens on doors, vents, and windows
• Use traps
• Use beneficial insects
• Use beneficial mites
• Use kaolin
• Use insecticidal soap
• Use neem
• Use spinosad
SYMPTOMS
Small, yellowish spots and speckles appear on leaves when true bugs stab leaves with needlelike mouthparts. Sites do not grow larger. Leaves may become distorted, turn brown, and wilt. Look for shield-shaped bugs crawling across leaves to confirm the diagnosis.
DIAGNOSIS
true bugs: southern green stink bug (Nezara viridula), tarnished plant bug (Lygus lineolaris), potato bug (Calocoris norvegicus)
SOLUTIONS
• Sanitize
• Weed
• Remove pests by hand
• Use traps
• Vacuum adult insects from the air
• Use beneficial insects
• Use beneficial fungi
• Use insecticidal soap
• Use neem
• Use horticultural oil
• Use pyrethrin
SYMPTOMS
Pale dots stipple the leaves. Leaf tips and edges turn brown (hopper burn). Leaves become coated with a clear, sticky, varnishlike substance on which gray-black mold grows. The plant may wilt. Look for small, wedge-shaped insects on the undersides of leaves that jump and fly away rapidly when disturbed.
DIAGNOSIS
leafhoppers: glasshouse leafhopper (Zygina pallidifrons), red-banded leafhopper (Graphocephala coccinea), potato leafhopper (Empoasca fable)
SOLUTIONS
• Sanitize
• Weed
• Use row covers
• Use screens on doors, vents, and windows
• Use beneficial insects
• Use beneficial fungi
• Use insecticidal soap
• Use neem
• Use pyrethrin