Clementine tree: the best varieties & tips for planting
Even in our latitudes clementine trees can be planted – you just need to know how. We present suitable varieties for pots and show you what to consider when caring for a clementine tree.
The fruits of the clementine tree taste somewhat sweeter and milder than the closely related mandarins and usually have no seeds. Moreover, compared to many other representatives of their citrus family, clementines are very easy to peel. This makes the citrus plant particularly popular. In a pot, the Mediterranean plant can also be cultivated in this country.
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Clementine tree: origin and properties
Both the geographic origin and the botanical origin of clementine are not clear. It is known that its name can be traced back to the French monk Frère Clément. Today, it is generally believed that clementine (Citrus clementina or Citrus × aurantium) originated as a hybrid by the accidental crossing of mandarin (Citrus reticulata) and bitter orange (Citrus × aurantium L.). It has been cultivated for a long time in Mediterranean regions. There are also large growing areas in some countries in North Africa as well as in Florida.
The clementine tree grows as an evergreen shrub or small tree with a round, compact crown. Potted clementines are usually grown as a half-height or standard tree. Under optimum growing conditions in the Mediterranean region, clementines can also grow up to 6 metres tall. The branches of the clementine are thin and rarely bear thorns. Clementine’s rich green foliage leaves have a lanceolate shape and a glossy, slightly leathery surface. In spring, delicate white flowers about 1.5 to 2.5 centimetres in size are formed. The flowers of the clementine have a pleasant sweet fragrance. Sometimes a second flowering occurs in the autumn. Clementines are self-pollinating but their flowers are also readily visited by insects and in this way are cross-pollinated.
Round fruits subsequently form from the fertilised flowers, which are botanically berries. The clementines are ready for harvest between November and March. With their orange skin, covered with numerous fragrant oil glands, they bear a strong resemblance to tangerines. What we buy in the supermarket as tangerines are actually mostly clementines. Inside, however, the closely related citrus fruits have some differences. The flesh of clementines is yellow-orange and thus somewhat lighter than that of tangerines. Clementines divide into 8 to 12 mostly seedless segments. Mandarins, on the other hand, consist of nine segments and have many seeds.
Clementine varieties for the pot
Clementine trees are not hardy in Germany and should therefore be planted in pots so that they can easily be placed in a frost-free location in the autumn. The ′Commune′ variety is an early variety whose fruits ripen quickly. The ′Red Ruby′ variety produces fruits with red skin and blackberry-red flesh. These have an intense sweetness and tangerine-like flavour. The ′Tardivo′ and ′Mandared′ varieties are late maturing varieties. Cultivation of these varieties of clementines in our latitudes is recommended only if there is a heated orangery or conservatory, where the fruit can safely ripen. The ′Mandared′ clementine is a relatively new cultivar from Italy that produces fruit with slightly darker flesh. Its taste goes slightly in the direction of blood orange.
Planting clementines
Clementine trees are planted in containers due to their low winter hardiness. From April, clementines can be placed outside on the balcony or patio. For this purpose, choose a location in full sun, protected from drafts. Since there is a risk of the clementine roots overheating in the summer, you should choose a planter in a light shade when planting. White pots reflect light and cannot heat up as quickly as dark pots. Choose a sufficiently large planter with a drainage hole so that excess water can run off when watering and no waterlogging can occur. Choose a pot large enough in which the clementine tree can grow well and grow old. After all, citrus plants do not tolerate repotting as well as other plants. Like all citrus plants, clementine does not like lime. Therefore, choose a nutrient-rich, low-calcium substrate with good water permeability and a pH of 5.5 to 6. Special citrus soils are offered in stores.
Alternatively, you can make a suitable substrate yourself: choose a peat-free potting soil, such as our Plantura Organic All Purpose Compost, and mix one-sixth each of sand and clay granules – such as bentonite – into the soil. Last but not least, it is recommended to add some acidic primary rock flour, for example granite or basalt flour. This creates a slightly acidic, permeable substrate in which the irrigation water can seep away well but the moisture is also retained for some time by the clay minerals it contains.
No matter what soil you use: you should cover the base of the pot with clay granules or shards of clay so that excess water can drain off well when watering and no waterlogging occurs. Then, place the root ball in the partially filled planter and fill it with substrate.
Tip: Plant the clementine slightly higher in the pot than other plants so that the root neck dries quickly when watering. Otherwise, it can easily develop rot at the root neck.
If you do not want to buy a clementine tree, you can grow your own clementine from a seed. However, you will need to be patient before you can enjoy the first fruits. If you have found seeds of your favourite clementine, you need to completely remove the pulp, and then dry the seeds at room temperature for about two days. Fill growing containers with a suitable substrate, such as our Plantura Organic Herb & Seedling Compost, moisten and insert the seeds. Place the containers in a bright, warm place and keep the soil moist with a spray bottle. The clementine seeds will germinate within 4 to 6 weeks. When the plantlets have fully rooted the growing containers, they should be repotted into larger pots. With a little luck, the clementine will bear its first fruits after a few years.
Tip: Clementines can also be propagated from cuttings. To do this, cut a young, flexible shoot about 10 to 20 centimetres long from another sapling. Cut it off at an angle at the bottom and stick it deep into a mixture of low-nutrient growing soil and sand. Moisten it vigorously and press down the shoot. Then, cover the pot with a plastic bag and put in a warm, not too bright place. By the way, until the pruning takes root and new leaves are formed, it may take several months.
- Perfect for herbs as well as sowing, propagating & transplanting
- For aromatic herbs & healthy seedlings with strong roots
- Peat-free & organic soil: CO2-saving composition
Clementine tree care
The clementine is a low-maintenance citrus plant. Young plants should be watered frequently with a small amount of water, older clementine trees need less frequent watering. Waterlogging should always be avoided. Therefore, it is best to be more cautious when watering. Too much water will cause rot at the base of the stem. Too little water, on the other hand, causes the leaves to curl up and fall off. However, they subsequently reshoot again. In winter, citrus plants should be watered especially sparingly. A small amount of water is enough to keep the soil slightly moist at all times.
Clementine trees in pots should be fertilised regularly during the growing season from April to November. For this purpose, a liquid fertiliser such as our Plantura Liquid Citrus Food is very suitable. It helps the plant to form many flowers, powerful fruits and strong roots. Fertilise the clementine every 1 to 2 weeks through the irrigation water. The dosage here is 3 to 5 ml of fertiliser per litre of water. In addition, once a year you should use a phosphate fertiliser such as superphosphate or double superphosphate to ensure adequate phosphorus supply to clementines.
- Perfect for all citrus plants & Mediterranean plants
- Liquid fertiliser for healthy plants & aromatic fruit
- Quick & easy application - child & pet friendly
Besides watering and fertilising, clementine does not require intensive care. Depending on the age of the plant, different pruning measures are necessary. In principle, after pruning the plant will sprout more but produce fewer flowers. Young plants need regular pruning in the early years to maintain the compact shape. In old plants, whole shoots should be removed or long new shoots should be pinched; however, cuts in the middle of shoots should be avoided, otherwise strange and worthless branching will occur. Dead branches should also be removed, while branches that are still green and leafless may remain.
When caring for the clementine tree, it should be further noted that citrus plants are reluctant to repotting. Therefore, always choose a sufficiently large container. If repotting is necessary, make sure that the root ball remains undamaged.
Overwintering a clementine tree
Clementines are among the most cold-tolerant citrus plants. Older clementine trees usually survive short-term frosts to a maximum of -5 °C without damage. However, to make sure that your clementine tree survives the cold season well, it is better to overwinter it in a frost-free, bright place. In the autumn, place the pot in an unheated room in an apartment (for example, the stairwell) or in a garden shed and overwinter the clementine tree at a temperature between 5 and 15 °C. In spring, when no more late frosts are expected, the clementine can then move back to the balcony or patio. During the winter months, the plant does not require fertiliser and rarely needs watering. Provide it with a small amount of water occasionally so that the substrate never dries out completely.
Harvesting and storing clementines
Depending on the variety, the fruit can be harvested between November and March. If the clementines are stored in a cool place, for example in the refrigerator or cellar, they remain fresh and can be kept for several weeks.
Clementine nutrients
The low-calorie clementines, like other citrus fruits, are truly rich in vitamin C. Eating one clementine covers about one-third of the daily vitamin C requirement. In addition, clementines contain other valuable vitamins and minerals such as calcium and potassium.
If you want to learn more about clementines, you can learn interesting facts in our special article on the difference between manderines and clementines.
