Hinoki Cypress Bonsai

Hinoki cypress prefers to be kept moist, but not wet.  Do not let hinoki cypress completely dry out between waterings.

Water your hinoki cypress when you see that the surface of the soil is dry but the particles immediately beneath the soil still have moisture in them.

Hinoki cypress would be rated as a partial sun species. However, it can tolerate full sun in the northernmost climates where the sun is less intense.

As a bonsai subject, hinoki cypress is going to have very tight inner nodes and in the full sun, it runs the risk of burning and discoloring and may even die over a prolonged period of time due to that damage.

Hinoki cypress is particularly prone to burning after the pruning process, so providing it with some relief from intense sunlight—especially during the spring season—will be beneficial.

Ideally, your hinoki cypress will be placed in a part of your garden that offers full sun in the morning and some shade coverage in the afternoons.

Because the hinoki cypress has the ability to move a lot of water, it can tolerate fairly intense heat. However, the hotter the temperature, the more shade the hinoki cypress will need. 

At temperatures of 95°F or above, the hinoki cypress will require 50% shade, meaning  full sun in the morning and full shade in the afternoon. 

Hinoki cypress can tolerate cold temperatures down to 20-25°F as long as it’s a bigger tree with a larger soil volume. However, if your hinoki cypress is smaller or lives in a shallow tray, you might see some tips die or some portions of the tree struggle and suffer in these colder temperatures.

Hinoki cypress is a light to moderate fertilizer consumer at best. It’s a slow, delicate growing tree, so you want to respect that by not trying to make it do something that goes against its natural tendencies. 

The hinoki cypress prefers light applications of fertilizer when it’s in its refinement stages, and moderate applications when it’s in its development stages.

In the spring you should fertilize moderately as growth emerges up until you start to see the tree shutting down for summer dormancy. During the hottest part of summer, typically mid-July through August, you do not need to fertilize. You can then resume moderate fertilizing through the fall to help the tree amass its vascular tissue and continue to perpetuate its strength.

Hinoki cypress bonsai pruning is for structural and design purposes and should be done in the spring, prior to the onset of growth, or in the early fall, prior to the onset of vascular productivity.

However, when it comes to refinement, you can prune once in the late spring or early summer just to keep the tips refined and slow the rate of growth. This will help hold the shape of the tree.

If you do refinement pruning in late spring or early summer, be sure to offer  hinoki cypress a shady spot to recover so that you don’t expose that interior foliage to intense sunlight and run the risk of damaging the tree.

Your hinoki cypress can be wired in the early spring, prior to the onset of growth. This is when you can do the most reduction of foliage and the most significant bending with the faith that any damage will be patched. 

If you do plan to wire during the spring or summer months, it’s best to stick to refinement wiring, using small wires, and making only small moves. If you attempt to do structural and styling wiring in the hotter months you run the risk of damaging branches and increasing the potential for branch dieback.

Repotting your hinoki cypress is best done in the mid to late spring, prior to the onset of growth. Right as those tips are starting to show signs of growth, you should repot using one part pumice, one part lava, and three parts akadama soil mix. 

Akadama is both highly moisture retentive and nutrient retentive, while the pumice and lava allow the hinoki to exist inside of a bonsai container for a prolonged period of time, as the roots grow more slowly with this tree.

During the repotting process, you can reduce a significant amount of root mass, but you should never bare-root it. Always leave a portion of the native root system untouched.

When you reduce the roots you should never prune the foliage, but when the roots are reestablished, you can heavily reduce the foliage at the right times of the year.

Hinoki cypress is a challenging species to air layer, but it can be done. Propagation is best done by striking smaller cuttings from softwood or semi-hardwood. 

Typically, the large hinoki cypress trees come from the nursery industry where the trees have been allowed to grow freely.

Hinoki cypress is relatively pest and disease-free when it’s in a healthy state. There’s always potential for woodboring beetles to enter the living tissue of a weakened hinoki and lay their larva which can consume the cambium of the tree. 

But generally, the hinoki is a very durable, strong, and pest-free tree that is free from the issues other conifers have, such as aphids or spider mites.