What's eating my heart-leaved blechnum?

Heart-leaved Blechnum is a houseplant fern most threatened by spider mites, which thrive in dry indoor environments and quickly discolor its glossy fronds. Scale insects and mealybugs also appear on stems and undersides. Fungus gnats breed in waterlogged compost. Maintain good humidity and water consistently but not excessively.

Fine webbing, yellow or bronze stippling on frond undersides; fronds turn pale and dry in heated rooms Shower foliage regularly; keep humidity above 50%; apply insecticidal soap or neem oil spray every 5–7 days

Hard brown or tan bumps on petioles and frond midribs; sticky honeydew deposits and frond yellowing Scrape off and treat with rubbing alcohol; follow with horticultural oil spray every 2 weeks

White cottony clusters at stem bases and leaf axils; honeydew and sooty mold; reduced vigour Dab with alcohol swab; spray diluted neem oil every 7–10 days until pest-free

Root feeding from larvae causes wilting and yellowing; small black adult flies around compost Allow top inch of compost to dry before watering; use sticky traps; drench with Bti solution