Lubera’s top tips for oranges, lemons, limes, kumquats and more
Citrus fruits are among the most popular fruit to eat, yet many gardeners shy away from growing them, fearing the plants to be difficult to grow.
Like most things, once you know how, they’re easy – here are some excellent cultivation tips from Swiss fruit experts Lubera.
The citrus harvest focuses on the winter months – mandarins, clementines as well as fresh oranges but 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 but not if you grow your own.
Start with the right plants
Start off with the main varieties of lemons and oranges, which are easy to maintain and fruit reliably. Once used to growing them, expand your orangery a little at a time.
The most important thing is buying grafted, quality plants. You can grow plants from pips but they rarely flower, as supermarket fruit come 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).
Citrus plants are not hardy and must be protected in winter. An unsuccessful overwintering regularly affects the growth in spring and summer, leading to a poor or failed harvest.
In the colder months, place the plant in a cool and bright location, between 5-10°C.
The overwintering area needs windows or plant lighting. The overwintering should be as short as possible, as a rule, from mid-October to mid-April, shorter in mild regions.
Avoid living rooms, where there will be too little light, too much warmth, and dry air.
Growing season and caring for crops
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 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 fertilized during the growing season. Lubera’s Instant Citrus Frutilizer contains the ideal nutrient combination and an 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, which can also be bought at Lubera.
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.
citrus ripening and harvesting
In autumn, the growth of the small-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 it. 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 received while ripening. Mandarins and limes are less demanding, while you eat kumquats with the peel.
To see the full range of citrus fruits from Lubera click here.