Cypress trees: expert tips on planting & caring for cypresses
Cypress trees provide an atmosphere reminiscent of summer holidays. Discover the best cypress plant species and learn what to consider when planting and caring for these Mediterranean plants.
Towering cypresses that grow along roads and paths or decorate stone houses are a quintessential part of any Tuscan landscape. But they are also perfect for those of us who long for a little Mediterranean flair in our gardens.
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Cypress trees: origin and characteristics
Cypress trees belong to the conifer family known as Cupressaceae. Aside from Italy, cypress species also grow in other warm areas of the northern hemisphere, including Asia, northern Africa and in warm regions of North America. At least 12 million years ago, cypress plants were even native to what is now the UK, but the ice age succeeded in changing that. That said, cypress trees are becoming more common again in the UK.
Cypress trees are evergreen conifers that can reach impressive heights. For this reason, they make excellent hedges that provide ample privacy. Cypress tree leaves are generally needle-like and can vary in colour from dark green to silver-blue. When you rub the leaves between your fingers, the leaves emit an interesting, often quite pungent scent, the nature of which depends on the variety. Cypresses also produce small, spherical seed cones that have a woody outer shell to protect the seeds within.
Cypress plant species and varieties
At least 16 cypress species are known worldwide, but only a few of them are cultivated as ornamental plants in the UK. Not all species are sufficiently winter-hardy, and humidity and precipitation are also limiting factors. Specialty species are therefore rarely found in stores. Here are some of the most common varieties that can be grown in our part of the world:
- Mediterranean cypress trees (Cupressus sempervirens), otherwise known as Italian cypress trees, are probably the best known of all cypresses. These are the ones that adorn the landscapes of the Mediterranean and Tuscany. Reaching up to 45m in height, these columnar trees form extremely distinctive landscape features. Unfortunately, they are not particularly frost-resistant, and prolonged temperatures below -5 ° C can cause severe damage.
- Leyland cypress trees (Cupressocyparis leylandii) are ideal for beautiful and dense hedges. These hardy cypress plants are a hybrid of the Nootka false cypress (Xanthocyparis nootkatensis) and Monterey cypress (Cupressus macrocarpa). Therefore, the Leyland cypress tree is not a full-flowered cypress in the true sense, since one of its parent plants is a false cypress (Chamaecyparis). Nevertheless, it is wonderfully suited to gardens and grows extremely quickly, up to 1m per year. This species also has no problems surviving cold. Leyland cypress trees come in yellow or green.
- Kashmir cypress trees (Cupressus cashmeriana) are native to Bhutan, which is why they are sometimes known as Bhutan cypresses. In Tibet and Nepal, they are often planted in front of temples. Their blue-green, scaly leaves hang down from the branches, which give them a beautiful overall look. However, this species is not hardy in our latitudes and are therefore rarely found here in the UK.
- Yunnan Cypress trees (Cupressus duclouxiana) are native to the mountain forests of China and found at elevations above 3000m. Even though this species is popular in Britain, as an ornamental plant, it is only conditionally hardy. The absolute lowest temperature that Yunnan cypress trees can tolerate is -12 °C.
- Monterey cypress trees (Cupressus macrocarpa) are popular the world over. They are often found in the gardens of New Zealand and on the American coast, but can also be seen in this country from time to time. Their frost tolerance is between -6 and -12 °C. In harsh climates, these cypress trees can be contorted into bizarre shapes by violent winds. The ‘Goldcrest’ variety is often called the indoor or golden cypress because its leaves are a rich golden green. It is not hardy, but excellent as a houseplant.
- False cypress trees (Chamaecyparis) are a suitable alternative to cypresses that are much more cold-tolerant. Aside from the slightly flatter leaves, they look surprisingly similar to true cypresses.
Planting cypresses
Small cypress plants quickly develop into magnificent specimens. For this reason, it is important to space out individual plants when planting them. Keep a planting distance of at least 1m between each cypress tree. The same goes for planting cypress hedges — 50cm distance is the minimum.
In addition to distance, stability is also of great importance. Mediterranean cypress trees (also called columnar cypresses) grow very tall, so be sure to plant them carefully and firmly.
The perfect location for cypress trees
As residents of warm and sunny places, cypress plants prefer a sunny to partially shaded location. Pay special attention to wind protection. Most cypress trees are not very hardy, but a sheltered location, like near a wall, helps to protect them against cold winds. Cypress plants prefer sandy, humus-rich, well-draining soil with plenty of nutrients. A slightly acidic pH value between 5 and 6 is optimal. Our peat-free Plantura Organic All Purpose Compost, for instance, is suitable for this. It not only provides your cypress trees with all the nutrients they need, but also promotes a healthy soil life.
- Perfect for all your house, garden & balcony plants
- For strong & healthy plants as well as an active soil life
- Peat-free & organic soil: CO2-saving composition
Unfortunately, not all types of cypress trees are suitable for growing in the UK even under these conditions. Leyland cypress trees generally have very few problems. Mediterranean cypress trees, on the other hand, can only be kept in mild regions, e.g. wine growing regions.
How to correctly plant cypress trees
- Plant cypresses between September and May
- Only plant out young cypress plants from a height of 1m, as they are then much less sensitive to frost
- Dig a large hole
- Backfill lower layer with loose excavated material and, if necessary, add some sand or gravel to improve drainage
- Take the root ball out of the pot and loosen up a little with the hands
- Place root ball in the hole and cover with excavated soil
- Lightly press down the soil and water well
- Add a layer of bark mulch around the plant to prevent the soil from drying out so quickly
Planting cypress trees in pots
Keeping cypress plants in a pot is a good alternative in regions that are too cold to plant them outside. This allows you to move the cypress plant to a suitably warm place for the winter. Plant cypress trees in pots following the same principles as planting in the ground. Just create a drainage layer of gravel at the bottom of the pot. Also make sure to choose a large enough pot, as columnar cypresses can quickly begin to lean over. Large pots also hold more soil, so can store more water, so you will not need to water as frequently.
Caring for cypress trees
Cypresses are relatively low-maintenance plants which, with the right care, reward us with year-round green foliage. As long as the location is right, they will only need the occasional watering and protection from the cold in winter, if necessary. Aside from this, the main care measure cypresses need is annual pruning. That said, potted cypress plants need a little more attention than those planted outdoors.
Watering cypress trees
Cypress trees need varying amounts of water, depending on the species. Monterey and Yunnan cypress trees are accustomed to moisture. One layer of bark mulch prevents too much water from evaporating and keeps the soil moist. Outdoors, cypresses usually get enough water, but we recommend watering from time to time in dry summers and even winters. Do not let cypress trees dry out in their winter quarters. Ensure the soil remains slightly moist, but not wet.
Pruning cypress trees
Cypresses are known for their vigorous growth. Pruning cypress promotes compact growth and thus keeps them from becoming sparse or falling victim to snow breakage. Depending on the species, you can even trim these versatile plants into a hedge or clip them into ornamental shapes. A mild day in October is the perfect time to prune. Read how to properly prune your cypress plant in more detail here.
Fertilising cypress trees
All cypress trees like a generous portion of fertiliser in the spring. Adding some compost, manure or some of our Plantura All Purpose Plant Food, for instance, helps keep cypress trees happy and healthy throughout the year. Alternatively, you can use mineral fertilisers and even several home remedies.
- Perfect for a variety of plants in the garden & on the balcony
- Promotes healthy plant growth & an active soil life
- Long-lasting fertiliser that is free from animal products - child & pet friendly
Overwintering cypress trees
As cypresses originate from the warmer climates of the world, not all species are hardy. Some, for example the Leyland cypress trees, are sufficiently frost-resistant and can survive the winter outdoors without extra protection. For more sensitive species, such as the Monterey cypress and young cypress plants in general, a bright fleece can help against strong sub-zero temperatures. Simply wrap the cypress tree with this if strong night frosts are expected.
To prevent potted cypresses from freezing through, cover them with bamboo fencing or something similar. Wrap the bamboo around the pot generously and place some under the pot too.
If you have a Monterey cypress houseplant in your living room, move it elsewhere for the winter months. These plants need to overwinter in a cool place at 5 to 10 °C. However, since it also requires sufficient light, a cold room or hallway with a window is perfect.
Propagating cypress trees
Even though cypress plants are known for their vigorous growth, propagating them can be a lengthy process. They germinate very slowly and it also takes many years for cuttings to be ready to be planted outside.
- Propagating cypresses by seed: cypresses are monoecious plants, meaning they have both male and female flowers. Only fertilised female flowers develop into a cone, which carries the seeds. But in order for them to become germinable, the cone must mature on the plant for 2 or more years. This is where it gets exciting. Since cypress plants come from warm regions with a relatively high risk of forest fires, they have adapted. In order for new cypresses to take root quickly after a devastating fire, the cone will not open until it is exposed to high heat. This ensures that numerous seedlings grow immediately after a fire. So, to get the seeds, put the cone on a warm radiator until it opens. Sow the seeds into normal potting soil, place somewhere at around 10 °C and keep the soil moist. The seeds will germinate and young plantlets will start to grow after a few months, but it takes many years for them to reach an attractive size.
- Propagating cypresses by cuttings: propagating by taking cuttings is faster, though not significantly. To do this, cut a woody twig about 10cm long from the cypress tree in the spring. Remove all the secondary branches in the lower part of the cutting. Roots will later develop at these points. Now put the cutting in damp potting soil. To help ensure everything stays moist, place a transparent bag over the pot. As not all cuttings will take, it is best to take several to increase your chances of growing successful new cypress tree.
Are cypress trees poisonous?
When you cut cypress trees, the pungent, somewhat spicy scent of cypress will hit you. This smell is caused by the toxins in the plant. Although these have a healing effect in small doses, they are toxic to humans and animals if ingested. Therefore, keep grazing animals and rodents away from the cypress plant. Be careful with young dogs as well, because they like to gnaw on everything that gets in their way.
As a matter of principle, do not leave small children unobserved in the proximity of a cypress tree. It is best to teach your children about the fact that cypresses are poisonous early on.
Do not leave small children unobserved in the proximity of a cypress tree. It is best to teach your children about the toxicity of cypress trees early on.
