A fern plant has developed brown lumps along its stems and is leaving sticky droplets. The brown bumps are likely scale insects, which feed by sucking sap from the plant. To treat the infestation, wipe off visible scales with a damp cloth or cotton bud dipped in neem oil or insecticidal soap. Repeat weekly to catch new hatchlings. For severe cases, spray the entire plant with a neem-based solution.
Preventing future infestations is key. Quarantine new plants and inspect for pests. Keep plants dust-free, avoid overcrowding, and regularly check leaves for signs of scale insects. Catching them early can be challenging, but prevention methods can help eliminate the problem. If you have a plant dilemma, email [email protected] with ‘Houseplant clinic’ in the subject line for advice.
Source: https://www.theguardian.com/lifeandstyle/2025/aug/26/houseplant-clinic-what-are-the-brown-lumps-on-my-fern