Chamacyparis

Growing Guide: How to Successfully Care for Cypress and Dwarf Cypress Bonsai

Cypresses and dwarf cypresses are usually grown as outdoor bonsai in our climate. Growing a dwarf cypress as a bonsai offers a wonderful opportunity for creative shaping, as these trees grow quite dynamically and respond well to proper pruning. Frost tolerance may vary among individual species and cultivars, but generally speaking, to maintain a compact shape and vibrant color, caring for a cypress bonsai requires a consistent growing regimen, regular monitoring of watering, and ongoing pruning of the crown.

Where to place a cypress and how to water it?

A suitable location should be bright, sunny, and well-ventilated. Ample light is essential for cypress—prolonged shade causes the inner part of the crown to thin out and die, and the bare wood then has a very hard time regrowing. However, during hot summers, it’s safer to protect the root ball from overheating by placing it in shallow pots in light partial shade.

Proper watering of cypress bonsai requires consistency. Cypress trees prefer a uniformly moist substrate, but it must not remain constantly wet or muddy, so that the roots do not suffer from a lack of oxygen. Unlike pines, they cannot tolerate prolonged drying out of the root ball, to which they react by turning their needles brown. During hot summers, cypresses greatly appreciate having their crowns misted in the evening.

Substrate, Repotting, and Proper Fertilization

An airy and well-draining substrate is essential for healthy root development in cypress bonsai. The Bonsai Master potting mix, or alternatively the Bonsai Master AK-3 mix, has proven effective, as it allows for rapid drainage of excess water while maintaining the necessary aeration in the root zone.

• Repotting cypress bonsai: Repot younger trees more frequently (usually every 2 to 3 years); older specimens only need to be repotted once every 4 to 6 years. The ideal time is early spring, just before the growing season begins (late March to early April). When repotting, handle the roots carefully, taking into account the current condition of the tree and the potting mix.
• Fertilizing cypress bonsai: To promote dense and healthy foliage, apply organic fertilizer every 14 days from spring through late summer. In the fall, we reduce fertilization and switch to fertilizers with minimal nitrogen and a high potassium content, which helps the tissues mature properly before winter.

Frequently Asked Questions About Cypress Trees (FAQ)

Which cypress is best suited for growing as a bonsai?

For bonsai purposes, the Japanese cypress (Chamaecyparis obtusa) is best suited to our climate, particularly the 'Hinoki' cultivar, which has a beautiful fan-shaped arrangement of needles. The pea cypress (Chamaecyparis pisifera) in the ‘Boulevard’ cultivar, with its silvery-blue needles, is also very popular and hardy. With the Lawson cypress (Chamaecyparis lawsoniana), on the other hand, greater care is needed, as some of its cultivars are noticeably more sensitive when grown in pots.

How is a cypress shaped and pruned as a bonsai?

The crown is maintained primarily by gently pinching off the tips of young, soft shoots with your fingers throughout the spring and summer. If you were to trim these green tips with regular scissors, their edges would turn brown and the tree would lose its aesthetic value. Traditional pruning of cypress bonsai is used mainly on woody twigs, although with certain pruning techniques, you can also gently trim the green parts—but only very carefully. We use aluminum wire to shape cypress bonsai. While young shoots are pliable, older branches tend to be more brittle and prone to snapping. Furthermore, you must carefully monitor the wires to ensure they do not cut into the bark. Not all cultivars respond equally well to pruning and wiring.

How to properly overwinter a cypress bonsai?

Many cypresses are frost-hardy in open ground under our climate conditions, but in shallow bonsai pots they require thorough winter protection. There is a risk of the delicate roots freezing, and freezing winds can dehydrate the evergreen crown. The safest way to overwinter them is in an unheated, cold greenhouse or by burying the pot in the ground in a shady spot in the garden and protecting the root ball with pine needles or leaves. During frost-free winter days, don’t forget to water them lightly.

Is a cypress bonsai suitable for beginners?

We recommend cypress bonsai for moderately advanced growers. Although it grows relatively readily and its young wood is easy to shape, it is more sensitive to dry substrate and summer root overheating than some other hardier species. In addition, the grower must ensure that the interior of the crown is regularly cleared of old, dry needles throughout the season to allow light and air to reach the center of the tree.