African Spear with Scale Insects: Prevention & Cure

Sansevieria cylindrica

Susceptibility: Moderate Severity: Medium Difficulty: Easy

Scale insects are small sap-sucking pests that appear as brown, shell-like bumps on plant stems and leaves. There are over 25 species, divided into armored (hard) and unarmored (soft) scales. They feed by piercing plant tissue and extracting sap, which weakens the plant and can lead to yellowing, stunted growth, and even death if left untreated. They also excrete honeydew, which attracts ants and promotes sooty mold growth.

🔍 Symptoms

• Small brown rounded lumps on leaves and stems
• Shell-like or waxy bumps on undersides of leaves
• Yellowing or chlorotic (pale) leaves
• Sticky honeydew coating on leaf surfaces
• Black sooty mold fungus growing on honeydew
• Drooping or wilting leaves
• Stunted growth and reduced plant vigor
• Presence of ants feeding on honeydew

❓ Possible Causes

→ Introduction of infected plants from nurseries
→ Poor plant health making them more susceptible
→ Warm indoor environments favoring reproduction
→ Lack of natural predators indoors
→ Overcrowding of plants allowing easy spread
→ Stress from heat, drought, or poor care

💊 Treatment

⚡

Quick Fixes

Step 1

Blast affected plants with strong water spray from garden hose to dislodge scale insects

Step 2

Mix emergency soap solution: 1 tablespoon dish soap + 1 teaspoon vegetable oil + 1 teaspoon 90-proof alcohol + 1 quart water

Step 3

Spray solution directly on scale insects, focusing on undersides of leaves

Step 4

Physically wipe off visible scale with damp cloth or soft brush

Step 5

Repeat treatment every 2-3 days for one week

🌿

Organic Treatment

Step 1

Inspect plants weekly to identify scale insects in their crawler stage (before protective coating develops)

Step 2

Mix insecticidal soap: 1 tablespoon dish soap + 1 quart water in spray bottle

Step 3

Spray affected areas thoroughly, ensuring contact with insects, once daily for 3-4 days

Step 4

Apply horticultural oil (neem oil) to suffocate eggs, nymphs, and adults

Step 5

Physically remove visible scale by wiping leaves with damp cloth

Step 6

Introduce beneficial insects like ladybugs, lacewings, or parasitic wasps for ongoing control

Step 7

Apply fermented stinging nettle tea spray as additional organic treatment

🛡️ Prevention

✓ Carefully inspect all new plants before bringing them home
✓ Quarantine new plants for 2-3 weeks away from other plants
✓ Maintain plant health with proper watering and fertilization
✓ Ensure good air circulation around plants
✓ Regularly inspect plants, especially leaf undersides
✓ Keep plants properly spaced to prevent spread
✓ Encourage natural predators like ladybugs and lacewings

🌱 Care Guide: African Spear

💧 How to Water

Water every 2 weeks in spring/summer and only once a month in fall/winter. Allow the soil to dry completely between waterings. Use the "soak and dry" method.

☀️ Lighting

Adapts well to low light conditions but thrives in bright indirect light. Tolerates direct sun, but too intense light may yellow the tips.

🪴 Ideal Soil

Use well-draining substrate with pH between 6-7. Ideal mix: potting soil, sand, and perlite in equal parts. Avoid waterlogged soil.

See more: African Spear → See more: Scale Insects →