Symptoms
Poor flowering or flower buds drop without opening.
Causes
- Gardenias are sensitive to changes in the environment.
- Fluctuating day and night temperatures damage the flower buds.
- Irregular watering can cause bud drop.
- In summer temperatures above 18oC and a dry atmosphere can inhibit flower bud formation.
Prevention
- Keep gardenias in a room kept at a constant temperature.
- Avoid both dry conditions and waterlogging.
In winter:
Aim for a night temperature of 16oC, although 10-15oC will do.
Give plants as much light as possible.
In summer:
Keep night temperatures around 15-18oC, and ventilate to keep day temperatures below 24oC.
Maintain humidity levels by placing plants on a tray of moist gravel.