Lubera’s top tips for oranges, lemons, limes and more
Many gardeners shy away from growing oranges and related plants, but here’s a complete guide on how to grow citrus fruit from Swiss experts Lubera.
They’re not as difficult to grow as is believed, once you know the basic cultivation tips. The citrus harvest focuses on the winter months for mandarins, clementines and some oranges. However, the main varieties of oranges and lemons are available throughout the year.
The more exotic fruits – kumquats, sour oranges or bitter oranges are hard to get hold of in supermarkets or greengrocers, but not if you grow your own. Read more about flower and veg seeds sent to Syrian refugees.
How to grow citrus fruit – Start with the right varieties
Begin with the main varieties of lemons and oranges, which are easy to maintain and fruit reliably. Once you’re used to growing them, expand your orangery.
The most important thing is buying grafted, quality plants. You can grow plants from pips but they rarely flower, as supermarket fruit comes from plantation trees, which are mostly hybrids with limited fertility.
Lubera’s plants consist of a scion from a fruit-bearing mother tree, which is grafted onto a robust rootstock, usually either a trifoliate orange (Poncirus trifoliata) or a bitter orange (Citrus aurantium).
Overwintering plants
Most citrus plants are not hardy and must be protected in winter. For exceptions, see Lubera’s range of frost-hardy varieties frost-hardy varieties. Unsuccessful overwintering affects spring and summer growth, leading to a poor or failed harvest. In the colder months, plants go dormant. Place the plant in a cool and bright location, between 5-10°C. The overwintering area needs windows or plant lighting, from mid-October to mid-April, shorter in mild regions.
Under these conditions, the plants can cope with the smaller amount of light during our winter. Especially in the first half of the winter, citrus plants have a light deficiency at temperatures above 15°C, which leads to leaf fall.
Unheated rooms such as a stairwell, a garden house or a shed are well suited, as are greenhouses. Avoid living rooms, where there will be too little light, too much warmth, and dry air.
How to grow citrus fruit – Growing season and caring for crops
In spring, summer, and autumn, the plants need a sunny, open location. An ideal location is on balconies and terraces with full sun that are warm and protected.
After mid-April, the plant needs to be outside in direct sunlight so it can develop flowers and new shoots. Partial shade is not an option. Make sure small plants are not shaded by larger plants. If you have a choice between morning and evening sun, the morning sun is preferable, as it has less time in the cool shade.
Water only when the soil has dried out in the deeper layers, using a hygrometer or your finger. A container-grown plant must be regularly fertilised during the growing season. Lubera’s Instant Citrus Frutilizer contains the ideal nutrient combination and exact composition of trace elements. Fertilise weekly from May to August, but only if the plant also needs to be watered. Every two to three years, repot the plant in free-draining specialist soil.
Flowers and pollination
At the latest in April or May, the first buds appear in the leaf axils, with flowers in May/June. While the Four Seasons Lemon has year-round flowering, the oranges only have two flowering phases per year, one in the spring and one in late summer. Kumquats or limes only flower once.
Citrus plants are self-pollinating – from every flower, there is a fruit set. During the summer, they become significant, young fruits. The plant will probably drop some fruit buds, as younger, grafted plants develop more fruit buds than they can feed.
How to grow citrus fruit – Ripening and harvesting
In autumn, the growth of the small to medium citrus fruits is completed. Larger varieties, such as grapefruit, pomelo, and citron need longer and grow until next spring. The typical yellow or orange colour appears when the nights become cooler – the pigment is an “antifreeze” that protects fruits from frost damage. However, the colouration does not need frost; it is sufficient if the temperatures are about 5°C.
If the fruits bear their typical colour and do not grow further, they are ripe. Most citrus fruits will stay on the tree, so to harvest, you will need a pair of scissors to cut the fruit off. It is important not to use chemicals. Don’t eat fruits that were hanging on the tree when you bought them. Your first, own, untreated harvest can be used without problems.
A lemon tree can provide you with lemons all year round. The sweetness of the oranges depends on the amount of sun they receive while ripening. Mandarins and limes are less demanding, while you eat kumquats with the peel.
Sensitive to waterlogging
Orangery growers know how sensitive citrus plants are to waterlogging. Citrus plants should be watered only after the soil has dried, not just on the surface but also in the deeper layers, where the sensitive, fine roots are located. They should not be permanently moist. The vegetation period for citrus plants is limited in the UK. Therefore, it is important that the plants have enough nutrients when they are back in the sun.
The supply of nutrients from organic material, which is found in open soil, is lacking for potted plants, so give them a mineral fertiliser from May to August, specifically made for citrus fruit. The phosphate content is low, but the nitrogen and potassium content is higher. Trace elements, such as iron, magnesium, zinc, copper, manganese and molybdenum are also important. The fertiliser should be applied with the irrigation water.
Lemon recipe to cure a headache and cocktail lime
Cut a lemon in half, and squeeze the juice into some black coffee, which actually tastes good. Put the lemon peel on your forehead and temples, and close your eyes for about 20-30 minutes.
Who does not like to relax with a refreshing Caipirinha using self-harvested limes? The original fruit for this drink is the Mexican lime Messicana, which is sliced and crushed. With its sour, but also lime-like aroma, it can also create a special note in warm dishes and also in salads.
Mexican Lime Messicana
Growth: Compact, small leaves, fertile.
Flowers: Loads of white flowers.
Fruits: Thin peel, aromatic.
Overwintering: It is possible in a cold house, but it is better to overwinter in a conservatory.
PLEASE NOTE: Lubera no longer sells plants to the UK after Brexit. It is working on a solution to deliver directly to customers’ homes in the future.
For further information, visit www.lubera.co.uk.
