What's eating my pitton's houseleek?

Pitton's Houseleek (Sempervivum pittonii) as a houseplant faces the same succulent pest pressures as other Sempervivum — mealybugs nesting in the rosette's tight leaf pockets are the main risk. Root mealybugs can also colonise the base unseen. Fungus gnats breed when soil stays too wet. Mealybugs are the dominant indoor threat for this compact alpine species.

White powdery or cottony clusters between rosette leaves; reduced vigour and discoloured foliage. Treat individually with an alcohol swab; follow with a neem oil spray over the whole plant; re-inspect after 10 days.

Plant droops without visible above-ground pest signs; white colonies visible on roots when unpotted. Remove from pot, wash roots, allow to dry, drench in dilute neem, repot in fresh gritty succulent compost.

Larvae damage surface roots in waterlogged soil; adults hover at pot level. Water only when compost is completely dry; use Bti as a soil drench; sticky yellow traps help monitor adult numbers.