What's eating my pelargonium odoratissimum?

Pelargonium odoratissimum (apple-scented geranium) is vulnerable to aphids, whitefly, and spider mites, especially when grown as a houseplant or conservatory plant. Botrytis grey mould can rot stems in humid conditions. Aphids clustering on succulent new growth are the most common and damaging pest.

Soft insects massed on shoot tips; sticky honeydew, curled leaves, and stunted growth. Remove with water jet or insecticidal soap; neem oil spray; use Aphidius parasitic wasps under glass.

Clouds of white insects when plant is touched; yellowing sticky leaves with sooty mould developing. Sticky yellow traps; insecticidal soap or pyrethrin spray applied weekly until clear.

Pale stippling on leaf surfaces; fine webbing on undersides; worst in warm, dry indoor environments. Mist leaves regularly; apply neem oil or predatory mite Phytoseiulus persimilis for biological control.

Grey fuzzy mould on stems and leaf bases, especially at soil level in cool, humid conditions. Improve airflow; remove affected plant material promptly; avoid overhead watering; apply a copper-based fungicide if severe.