Chapter 86 Chamaecyparis obtusa, C. pisifera, C. lawsoniana

86.1 Hinoki cypress, Sawara cypress, Lawson’s cypress

Lawson’s cypress forest scene. Link to original image.

A well-styled Hinoki cypress. This species is challenging to style well because of its habit of constantly pushing the green tips outward and allowing the inner foliage to brown out, making it hard to maintain tight foliage pads. Link to original image.

A Sawara cypress. This particular foliage is from the ‘Plumosa’ cultivar. Link to original image.

86.2 Soil: General Deciduous / Rich Conifer Mix

Ratio: 3 parts bark, 1 part grit

Add-ins: dolomitic limestone (~5 lbs/yd), Tree-Tone (15 lbs/yd)

pH: ~6.5 (slightly below neutral)

Moisture: Average to moist. False cypress trees grow best in cool, porous, moist soil that’s neutral to slightly acidic. Hinoki cypress in particular thrives in our humid climate.

86.3 Light

Routine: a false cypress tree does best in an area that gets full sun for six hours a day. Avoid areas that get direct sun the majority of the day because the tree could develop sun scorch.

86.4 Cultivation Notes

Chamaecyparis is a popular genus for bonsai however it is difficult to maintain it’s appearance and is difficult to style well. When finding specimens for use as bonsai or when styling, always consider the existing branch placement as Chamaecyparis only back buds on green branches and rarely on mature wood.

86.4.1 Potting & Root Pruning

Schedule: repot in later part of spring, on a similar schedule as other conifers.

86.4.1.1 Top & Branch Management

Heavy pruning: prune wood in mid-summer when wounds will heal. Avoid pruning large branches if at all possible.

Fine pruning: when the upright branches of a cypress tree forks, you can prune it. Cut into new wood, rather than the older brown branches. Prune back dead branches, as well as those that seem out of place, in order to keep the tree looking its best. Ideally, prune during the summer months.

Chamaecyparis do not backbud on anything other than green wood.

Leaf pruning: pinch out foliage continually through growing season to keep compact. Clear dead brown foliage in late fall or early winter to allow buds to break on older wood.

Wiring: false cypresses are easy to wire, but branches may take a while to set and may need to be re-wired several times to avoid cutting in to the tree. Can be wired at any time of year, but wait three months after repotting to wire.

86.4.2 Feeding

Feed every 2 weeks from early spring to mid autumn with Miracid, or monthly with an organic fertilizer for conifers. Water blue-colored cultivars a few times each season with 1 teaspoon/gallon epsom salts. The added magnesium will intensify the blue color.

86.4.3 Pests & Problems

Cypresses are extremely disease resistant but stressed trees can develop cankers or needle blight. In the case of cankers, trim off browning limbs. For needle blight, look for yellowing needles and green pustules near the end of the stem. For both problems, spray with a copper-based fungicide.

86.4.4 Winter Storage

Store in mulch outdoors, in a location that allows some sun. Must be protected from strong wind particularly during winter.

86.5 Propagation Notes

Cypresses are difficult to propagate, but are readily available from garden centers.

86.6 Artistic & Styling Notes

In my experience, these species do not respond well to being forced into a particular style. They seem to do better in a less formal, more natural style that emphasizes overall silhouette, not strict branch placement.

86.7 Additional Information

86.7.1 Natural History

Despite their common name, Japanese or Lawson’s cypress is native to western North America. Hinoki and Sawara cypress are both natives of Japan.

86.7.2 In Cultivation

Hinoki cypress (Chamaecyparis obtusa) is a broad, conical tree with soft, stringy bark. Flat, fan-shaped foliage is dark-green when mature with bright white bands underneath. Can reach heights of 70 feet in its native Japan.

Many varieties are available. ‘Nana Gracilis’ and ‘Yatsubusa’ are dwarf types with more compact growing habits. ‘Nana Gracilis’ loses inner foliage easily which it does not replace.

Japanese or Lawson cypress (Chamaecyparis lawsoniana) is a tall, narrow-pyramidal, scaly-leaved, evergreen conifer with short spreading branches and flattened twigs. It is the tallest member of the cypress family. In its native habitat, it will grow over time to 110-175’ (sometimes to 200’ or more) tall and to 4-6’ in diameter, but usually much shorter (to 40-60’ tall) in cultivation.

The original species is a huge tree that is infrequently grown in landscapes. Compact and dwarf cultivars are used more often for ornamental plantings.

Sawara cypress (Chamaecyparis pisifera) is a broad, conical tree with an open crown and finely peeling, red-brown bark. Pairs of sharply pointed, bright-green mature leaves, marked with white underneath, are produced in flattened sprays. Can reach heights of 70 feet in its native Japan.

Varieties include ‘Boulevard’ which has steel-blue foliage and ‘Plumosa’ with more frond-like foliage that is bright-green when young.