Orange Trees

Orange trees originally come from China but have been grown in Europe and North America for over 100 years. Orange trees are now grown all over the world for their delicious and nutritious fruit. There are many varieties to choose from, including Jaffa oranges, Navel oranges and Blood oranges. Many orange trees can be grown in the UK, under cover such as in a conservatory or greenhouse. They are not hard trees to grow in the UK as long as they are looked after properly.

About Orange Trees

Orange trees are evergreen (they don’t lose their leaves in autumn). They grow up to 8-15m. high if given the right conditions. Their leaves are dark green and waxy and their flowers are white and delicately scented. The fruits take up to six months to reach their full size and ripen, but are well worth the wait. Once they are ripe, they can be eaten straight from the tree, or left on the branch until you’re ready to eat them. They retain their flavour this way, where as if you plucked them from the tree and stored them, their flavour would diminish.

Growing Orange Trees

Orange trees are best grown in a large pot full of rich, organic matter. They suit a well-lit position, free from draughts. For smaller trees, a windowsill is ideal, and larger plants will benefit from a humid greenhouse or conservatory environment. In the summer months, stand them in a dish of wet gravel or mist them with water every day to encourage humidity, and place them outside if it is warm enough – they love to be outside. They can tolerate temperatures as low as 4°C, however, so I you live in the south and they are in a sheltered spot, you may be able to keep them outside throughout the year. Cover them with thick layer of fleece, so any frost can’t get to them.

Tips for Growing Orange Trees:

• If kept indoors throughout the year, remove dust from their leaves regularly, so the plant can breathe
• Ensure temperatures in your conservatory or greenhouse don’t get too high
• Keep your orange tree away from radiators as they can put the trees under stress
• Keep them cool, but protected from frost during winter – this mimics their natural growing conditions
• Water less during winter but don’t let the pot dry out completely, and increase the amount in spring
• Check the soil before you water the tree – too much water can kill them
• Feed weekly during the summer with a special citrus tree fertiliser – this gives them all he nutrients they are used to absorbing in their natural conditions. An organic alternative is a seaweed solution
• Top up the soil in the pot every spring with fresh compost
• Prune branches to 10-15cm long in February to keep the tree compact and healthy

Flowers and Fruit

Orange trees will normally flower in May, but if grown indoors they can flower at all times of the year, even December. They are self-pollinating (you will only need one tree to produce fruit) but very few of the flowers will turn into fruit, and you will find that many of the young fruit drops from the tree at various stages of their growth. Misting the flowers daily, however, will prevent this from happening.

As the fruit develops it will get larger and larger, and start to turn orange around Christmas time. It is thought that the cold weather acts as a trigger for the colouring of the fruit.

Orange Trees and Leaf Drop

Some leaf drop is normal but if large numbers of leaves fall check to see if the soil is too dry. Water well and mist the plant every day to increase humidity. Too much water can be fatal though, so if the compost is very moist, let it dry out before watering again. Make sure the tree gets plenty of light, as this can encourage the leaves to drop also.

Orange Trees and Pests

The most common pests to affect orange trees are aphids and mealy bugs. They will hide under the leaves and in the stems of the tree and suck out the sap from the leaves and the fruit. Mealy bugs leave little deposits all over the plant that look like cotton wool, and both pests will secrete a sappy substance, which covers the leaves. This can potentially kill the plant as the substance stops the leaves from being able to breathe properly, and a sticky black soot can form on them, preventing any light from reaching the leaves.

The best way to deal with aphids and mealy bugs is to wash them off the leaves and stems and regularly inspect the tree for signs of them. You will also need to sponge down the leaves to remove the sappy secretion and black soot, so they can breathe properly. If you do resort to chemical sprays you will still need to remove the pests from the tree and wash it down, so it’s easier to leave the sprays and deal with the problem naturally (this will also help the plant recover more quickly).

Pests are not very common on citrus trees, however, so you shouldn’t have too many problems. If you do have to deal with an infestation, all your hard efforts will be worth it when you get your first taste of a delicious orange, plucked straight from the tree.