Succulent & Agave Pest & Disease Guide: Root Rot, Scale & Black Spot

Succulents and agaves are hardy plants, but they do require attention when it comes to damage from overwatering and pests. Here is a summary of common problems and their solutions.

Root Rot

The most common issue for succulents and agaves.

Symptoms - Lower leaves turn yellow and become translucent - Stems become soft and mushy - A foul smell emanates from the soil - The plant wobbles when touched (roots have decayed)

Causes - Overwatering or watering too frequently - Soil with poor drainage - Pots without drainage holes - Watering during dormancy periods

Treatment - Remove the plant from its pot and cut away all rotted roots with sterilized scissors - Let the cut surfaces dry for 2-3 days in a shaded, well-ventilated area - Replant in fresh, well-draining soil - Wait at least one week before watering again

Prevention - Use well-draining soil (pumice, perlite, or specialized succulent mix) - Always use pots with drainage holes - Allow soil to dry completely between waterings - Reduce watering in winter and during dormancy

Pest Damage

Mealybugs: White, cottony clusters that appear on leaves and stems. They suck plant sap and weaken the plant. Remove manually with a cotton swab dipped in rubbing alcohol, or apply a systemic insecticide.

Scale insects: Brown or black bumps that attach to stems and leaves. Difficult to remove once established. Scrape off manually or use a horticultural oil spray.

Spider mites: Tiny pests that cause yellowing and fine webbing on leaves. Increase humidity and spray with miticide. Regular misting helps prevent infestations.

Root mealybugs: White, powdery pests found on roots during repotting. Wash roots thoroughly, treat with a systemic insecticide, and repot in fresh soil.

Sunburn

Agaves and succulents can suffer sunburn when suddenly moved from shade to direct sunlight. White or brown patches appear on leaves. Acclimate plants gradually to increased light over 1-2 weeks. Damaged leaves will not recover but new growth will be healthy.

Cold Damage

Frost-tender succulents and agaves can suffer cold damage when temperatures drop below their tolerance range. Affected tissue becomes translucent and mushy. Move plants indoors before frost, or protect with frost cloth. Remove damaged leaves once the threat of frost has passed.

BriChoku offers a wide selection of healthy succulents and agaves from specialized breeders who can advise you on care tailored to your growing conditions.