Chamaecyparis pisifera, the Japanese threadleaf false cypress shrub, boast showy, weeping, greenish-gold to gold colorbred foliage. The different cultivars of this shrub have scaly, golden foliage that is string-like in form. This colorful genus is a favorite among American gardeners who plant 'Gold Mop' and other popular varieties for their bright golden foliage during the spring season, and some varieties do a good job of retaining this bright color during the summer as well. Plant threadleaf false cypress in the spring after the last frost, and have patience for this shrub with its slow growth rate of a couple of inches per year.
|Common Name||Japanese false cypress, Sawara false cypress, gold mops, golden mops false cypress, sun gold, king's gold|
|Botanical Name||Chamaecyparis pisifera|
|Plant Type||Shrub, tree|
|Mature Size||6-30 ft. tall, 3-7 ft. wide|
|Sun Exposure||Full, partial|
|Soil Type||Clay, silt, loam|
|Soil pH||Neutral, acidic, alkaline|
|Hardiness Zones||4-8 (USDA)|
Threadleaf False Cypress Care
With their fine texture, threadleaf false cypress shrubs are great for giving your landscape visual interest, and their golden foliage opens up some interesting options when developing landscape color schemes. For example, when you use deep red barberries as a companion to the golden foliage of a false cypress, it creates an instant focal point. It's a bonus that deer usually don't feed on these low-maintenance shrubs.
When planting, dig a hole that is two to three times as wide as the root ball and six inches deeper than the height of the root ball. If your soil is heavy clay or sand, amend it with a planting mix or compost. Water the new plant well and place a two-inch layer of organic mulch around it, but be sure to keep the mulch a few inches away from the base of the plant to prevent rot.
Shrubs in the threadleaf group generally want full sun (but only partial sun at the southern end of their range). If the plant doesn't receive enough sun you might not see as much of the desired golden colors and the shrub foliage might get sparse and leggy. In warmer areas, a spot that gets morning sun but afternoon shade is a good choice.
These shrubs do well in a variety of soil types if there is good drainage. If you have sandy soil you might need to amend it with organic matter such as compost. They generally prefer acidic soils, but check for the specifics of the variety you will be planting.
The ground should be kept evenly moist, often requiring watering once a week in summer until the plants becomes established. Once established, they will suffer if overwatered. In general, established shrubs do not need to be irrigated. These shrubs are drought-tolerant and you only need to give them extra watering during prolonged dry spells. A three- to four-inch layer of mulch can help retain moisture in the soil, especially if they are placed in a spot where the soil dries out quickly and doesn't receive effective rainfall.
Temperature and Humidity
Different varieties of threadleaf false cypress have slightly different hardiness zones. Do some research to learn the varieties that do best in your local area. Generally, these plants can handle summer heat without too much fuss. They do appreciate some protection from strong winds, however.
Threadleaf false cypress can benefit from fertilizer in the early spring. While established plants can do fine without fertilization, fertilizing will help them produce the best color. A younger plant in which you want to encourage growth might do best with a fertilizer such as 10-10-10, while established plants that are not growing as much could use a 4-8-8 fertilizer. For the amount to use, follow the product label instructions.
Types of Threadleaf False Cypress
- 'Golden Mop' is a compact variety, two to three feet tall and wide, that is suitable for USDA plant hardiness zones 5 to 8. They bear scaly leaves that keep their golden color, provided the shrub receives enough sun. It can get winter burn in cold climates.
- 'Filifera Aurea Nana' grows four feet tall and wide and is suitable for planting in zones 4 to 9. The new growth is golden yellow and retains its color during the growing season before fading in autumn.
- 'Sungold' is a large variety that can reach up to 30 feet tall. It is suitable for planting in zones 3 to 7. Foliage emerges as bright gold and matures to lime green. This shrub does not keep its color quite as well through summer as does 'Golden Mop', but it does a better job of avoiding winter burn.
- 'King's Gold' is suitable for planting zones 4 to 8. It retains its golden color through the summer if it is grown in full sun six to eight hours per day.
This shrub requires very little pruning and you should avoid doing so if you want to keep its unique shape and foliage. Heavy pruning will ruin its unique appearance; thus shrub looks best when it's unpruned. You can, however, remove dead, damaged, or diseased branches at any time. If you must prune for shaping and to reduce its size, do so in the spring before new growth emerges.
Propagating Threadleaf False Cypress
Threadleaf false cypress can be propagated easily through hardwood cuttings. Here's how:
- With sharp pruners, cut a four-inch hardwood section during the winter and remove the foliage from the bottom two inches.
- Dip the cut end in rooting hormone and place it in moist, well-drained soil. A plastic bag over the cutting will help it retain moisture, but make sure the bag doesn't touch the cutting.
- Keep it warm and water when necessary. It might take some time for roots to form.
- When a root system develops, place the new sapling in a sunny area until it's ready to be planted outdoors.
How to Grow Threadleaf False Cypress From Seed
If you're patient, you can propagate threadleaf false cypress from seed. Follow these steps:
- Harvest the cones in the fall, allowing them to dry and open naturally.
- Remove the seeds and soak them in water for at least 24 hours.
- Retrieve the seeds that sank to the bottom (discarding those that float) and wrap them inside moist paper towels.
- Place the paper towel in a plastic bag and place the bag in the refrigerator for at least two months.
- When that cold-stratification time is up, sow the seeds in a quality potting mix.
- Keep the pot in a warm area. Expect germination to take at least three months.
- After germination, keep the pot in a shaded area for the first year, gradually getting the tiny seedlings accustomed to sunlight. They should be ready for the great outdoors during their second year.
Potting and Repotting Threadleaf False Cypress
Threadleaf false cypress varieties can be grown as container plants. Choose a smaller cultivar and a container that will allow it to grow for two to three years before needing to be placed in a larger container. The right size container is six inches greater diameter than the root ball for varieties that grow slowly.
Threadleaf false cypress is extremely cold hardy. If you have a potted cypress and you would like to give it a little protection in winter, simply put the container closer to your house or another structure protected from wind.
Common Pests and Plant Diseases
The threadleaf false cypress is fairly trouble-free with only the occasional spider mite attacking the foliage, turning it yellow. Black vine weevils sometimes feed on leaves and bark and their larvae feed on deep roots. Lay a cloth under the tree and gently shake the branches to catch these insects that tend to fall off easily. Scale insects may also appear because they like to suck on the juice of the cypress needles.
A blight fungus may land on a younger tree's twigs and foliage causing tips to turn brown and die. Trees over five years old seem to survive blight on their own and with little damage.
How long can threadleaf false cypress live?
This is a very long-lived plant, so be sure to plant it where it can thrive for decades and have enough room to reach its mature size. Some false cypress shrubs or trees have been known to survive for centuries.
Where should I place threadleaf false cypress in my home?
When in a container, this plant will enjoy bright morning sunlight and afternoon shade. Typically, these shrubs are best grown outdoors.
What are good companion plants for threadleaf false cypress?
Other types of false cypress can make great companion plants, as can a Buxus or Weigela.