Growing citrus in containers indoors means that plants can be sheltered from our less than perfect climate. However, ideal conditions are not always possible to achieve and this may result in a range of cultivation problems.
What are the problems?
The problems associated with growing citrus are due to unsuitable growing conditions. Any one or several of these problems may occur:
- Failure to flower
- Flowers drop before fruit sets
- Yellowing of leaves
- Loss of leaves
- Fruit fall
- Rotting roots
One to watch...
The citrus longhorn beetle, Anoplophora chinensis, is a non-native wood-boring pest that can cause serious damage to a wide range of broad-leaved trees and shrubs. It is not yet established in the UK and is considered a quarantine pest in the European Union. However, our web profile contains more information.
Here are the explanations for some of the most common problems:
Failure to flower: Lack of light, lack of feeding, erratic watering, or low temperatures can all cause this problem. If a citrus plant is grown from pips it will often not fruit for a number of years as they have to go through a juvenile stage before flowering. An average time for trees grown from seed to fruit is seven to ten years. Commercially, citrus are propagated by budding or grafting and can flower and fruit after only after two or three years.
Flowers fall before fruit sets: Dryness at the roots and lack of air humidity can cause failure to set fruit. Flowers do not need artificial pollinating.
Yellowing of leaves: There are several possibilities. The roots could be too wet or too dry. Draughts, low temperatures, or lack of feeding will also result in yellowing leaves.
Loss of leaves: This can be caused by draughts, too low or high temperatures in winter, often coupled with too much water in winter. Citrus prefer a cool winter rest. Provide lemons with a minimum winter night temperature of not less than 10°C (50°F) and calamondin oranges with 13°C (55°F).
Fruit fall: Fruits should ripen in a period of warm sunny weather, taking almost a year to develop to full size. Most cultivars set too much fruit for the size of the plant. Some of these will be shed, or clusters should be thinned to one fruit each on young plants.
Rotting roots: The first sign may be leaf fall or yellowing often caused by overwatering. Cut away damaged roots with some of the compost and repot into a smaller container.