What's eating my peacock fern?

Peacock fern (Selaginella uncinata) is most threatened indoors by spider mites, which thrive in the dry air this moisture-loving plant hates. Fungus gnats exploit its constantly moist soil, and mealybugs occasionally shelter in the dense mat of stems. Keep humidity high and soil consistently moist to discourage mite outbreaks.

Fine webbing over the fronds, bronzing or silvering of the iridescent blue-green foliage, and tiny moving dots on the undersides of stems. Raise humidity immediately; mist thoroughly and move away from heat vents. Wipe stems with a damp cloth, then apply insecticidal soap or neem oil spray weekly for three weeks.

Adult gnats hovering around the soil; larvae feed on fine roots, causing wilting and yellowing despite adequate moisture. Allow the top 1 cm of substrate to partially dry between waterings where possible. Use yellow sticky traps for adults; drench soil with Bacillus thuringiensis israelensis (Bti) or beneficial nematodes (Steinernema feltiae) to kill larvae.

White cottony fluff at stem joints and leaf axils; sticky honeydew followed by sooty mold; weakened, distorted new growth. Dab individual colonies with a cotton swab dipped in 70% isopropyl alcohol. For heavier infestations spray with insecticidal soap or neem oil, reaching stem junctions. Repeat every 7–10 days.