Gardenia pests and diseases: how to recognise them

At a glance

How to grow gardenia · All pests and diseases

Pests

• Scale insectsSmall round or oval bumps on stems and along leaf veins, mostly underneath, that do not move and look like shells or scabs.Photo: BARAKAT2011, CC BY-SA 3.0, Wikimedia Commons
• Two-spotted spider miteFine pale stippling or mottling on the upper leaf surface; leaves may turn bronze.Also called: red spider mitePhoto: Gilles San Martin from Namur, Belgium, CC BY-SA 2.0, Wikimedia Commons
• WhiteflyClouds of tiny white-winged insects, about 1.5 mm long, fly up when the plant is disturbed.Photo: gaucho, CC BY-SA 3.0, Wikimedia Commons

Diseases

• Grey mouldFuzzy grey-brown mould on decaying buds, flowers, leaves, stems or fruit in humid weather.Photo: Schlaghecken Josef, CC BY 4.0, Wikimedia Commons

Which gardenia problems need quick action?

These spread or do lasting harm fast; check the plants and start treatment the day you see them.

• Grey mould: Small, almost translucent spots that turn brown and water-soaked; affected tissue goes soft, dark and dies, and buds and flowers shrivel.

Plants with many of the same problems

• Geranium (4)
• Tuberous Begonia (3)
• Chrysanthemum (3)
• Coleus (3)
• Cucumber (3)
• Cyclamen (3)
• Gerbera (3)
• Grape (3)

Which plants each problem affects: sources

The links between these problems and the plant were checked against these pages.

1. rhs.org.uk/plants/gardenia/how-to-grow
2. rhs.org.uk/plants/7605/gardenia-jasminoides/details