The aroma of citrus fruits reminds us of sunshine and warm temperatures, which is exactly what citrus trees thrive in. Many of us would love to grow our own citrus fruits, but unfortunately, we don’t live in a sunny state in America or the Mediterranean. The good news is that there are several hardy citrus tree varieties. In this article, I want to teach you more about growing citrus trees in our climate (USDA Zones 7 to 9).
First some basic principles for growing citrus in Belgium or the Netherlands
The climate in Belgium and the Netherlands falls under USDA zones 7 to 9. Temperatures in these zones can drop from -1°C to -15°C in the winter. Citrus fruits, and especially young citrus trees, do not tolerate such temperatures well. However, there are a number of things you can do to protect citrus trees in our cold winters.
Protect your citrus as much as possible from cold northern winds.
First, choose your planting location carefully. Protect your tree from the cold north winds as much as possible. It is important to choose a planting location that not only gets plenty of sun and has excellent drainage, but also one that offers protection from the cold. Trees planted on the south or east side of a house will have maximum protection from the wind and from the radiated heat of the house. Ponds and other water features or overhanging trees also help to retain heat.
The first 2 to 3 years your citrus tree is still very sensitive to cold temperatures because the plant is still small. Make sure that if your plant is in a pot that the pot drains well because citrus does not like wet "feet". If necessary, put larger pots on wheels so that you can easily move your tree to a more sheltered spot. In the winter, the citrus tree should not be too warm because then there is not enough light available. A veranda that is not heated or a garage with a large window (and lots of light) is ideal.
A good layer of mulch around the base of the tree will help prevent the roots from freezing. You can also wrap your tree in bubble wrap and fleece when cold temperatures are approaching for even more protection. Cover the tree completely with two layers - first wrap the tree in fleece and then in plastic. Bubble wrap alone will cause the leaves to freeze to the plastic due to condensation, so be sure to use one or two layers of fleece as well. Once your citrus tree is 2-3 years old, it can tolerate lower temperatures better and recover from frost much more easily than young trees.
The best varieties of winter-hardy citrus fruits for Belgium and the Netherlands
There are both sweet and sour citrus varieties that are suitable for growing in our zones, provided there is adequate protection from cold temperatures. Choosing the right rootstock is important for winter hardiness. Look for plants that have a rootstock of the wild lemon (Poncirus trifoliata). Wild lemon is the best choice for cold hardiness and can tolerate temperatures down to about -18ºC.
1. Kumquats
Kumquats are small, oval citrus fruits related to oranges. Kumquats are a great addition to salads or eaten as a snack.
The kumquat tree is considered an evergreen tree that can grow up to 15 feet tall if left unpruned. In addition, the kumquat tree is very drought tolerant and does not require much water to thrive. The kumquat tree is best planted in the fall and will bear fruit in the spring.
Caring for kumquats is simple - make sure to fertilize them twice a year and water them regularly. Prune the tree in spring and summer to maintain its shape.
2. Satsuma Mandarin
Satsumas are mandarins that are almost seedless and have a sweet, but tangy flavor. Satsumas are often used in salads or as a snack because of their small size. The Satsuma tree produces white or pink flowers in the spring, which give off a sweet scent. Unpruned, Satsumas usually grow to a height of 3.5 to 4.5 meters.
When planting a Satsuma tree, make sure to place it at least 20 feet away from other trees or buildings. Full sun and well-drained soil are best for these trees. They are winter hardy and can withstand temperatures as low as -20°F.
3. Clementines
Clementines are a type of mandarin orange that are smaller and sweeter than other types of oranges. They are also seedless and have a thin skin that is easy to peel.
The clementine tree is a small evergreen tree that only grows to a height of one metre. Its leaves are dark green with a red edge and it produces fragrant white flowers in the spring. The clementine tree is winter hardy and can tolerate temperatures as low as -8°C. It is important to keep the soil of the clementine tree moist, especially during the summer months. Caring for your clementine tree is relatively easy and it will bear fruit during the winter.
It is advisable to plant clementines in large pots so that they can be brought indoors during the colder months.
4. Navel orange
These oranges are seedless and have a thick skin that is easy to peel. Most navel oranges are used for juicing because of their high sugar content.
The navel orange tree is a medium sized tree that can grow up to 6 metres tall if left unpruned. It is best planted in the autumn and will bear fruit in late winter or early spring. The navel orange tree is winter hardy and can withstand temperatures down to -6°C.
Like all citrus trees, navel oranges prefer full sun and well-drained soil. During the winter, your navel orange tree may lose its leaves, but it will start growing again in the spring.
5. Meyer lemon
Meyer lemons are considered less acidic than other lemon varieties and are a cross between a lemon and an orange or mandarin. These lemons have a thin skin that is fragrant and easy to peel. They are also sweeter and juicier than most lemons we know today.
Meyer lemon trees are a small tree that can usually grow up to 3.5 meters tall and are an excellent choice for growing in Belgium and the Netherlands. Caring for a Meyer lemon tree is relatively easy - it only needs full sun, well-drained soil and occasional watering. Because they are small trees, Meyer lemons are often planted in large pots so that they can be moved indoors to protect them from the cold.
6. Pomelo
Pomelo trees are native to the Far East, particularly Malaysia, Thailand and southern China, and grow wild on the riverbanks of Fiji and the Friendly Islands. It is considered a lucky fruit in China, where most households preserve pomelos during the New Year to symbolize the year's abundance.
The pomelo tree itself has a compact, low canopy that is somewhat rounded or umbrella-shaped, with evergreen foliage. The leaves are ovate, glossy, and medium green, while the spring flowers are conspicuous, aromatic, and white. The flowers are so fragrant that their scent is used in some perfumes. The fruit comes from the tree in winter, spring, or summer, depending on the climate.
Finally, about growing citrus in Belgium and the Netherlands
So, if you take the basic principles into account and protect your citrus well in the winter, you will be rewarded with the southern fruits from your own garden.
Hopefully I have been able to inspire you or remove your doubts about growing citrus in our climate.
Warm greetings, Sarah
