If you are looking for a tree suitable for a xeriscape landscape, one with ornamental attributes which also fulfills a valuable niche for wildlife, look no further than the Chinese pistache tree. If this piques your interest, read on for additional Chinese pistache facts and care of Chinese pistache.
I. Appearance and Characteristics
Pistacia chinensis, the Chinese pistache (Chinese: 黄連木; pinyin: huángliánmù), is a small to medium-sized tree in the genus Pistacia in the cashew family Anacardiaceae, native to central and western China.
It is hardy, can withstand harsh conditions and poor quality soils, and grows up to 20 m (66 ft). The leaves are deciduous, alternate, pinnate, 20–25 cm long, with 10 or 12 leaflets, the terminal leaflet usually absent. The flowers are produced in panicles 15–20 cm (5.9–7.9 in) long at the ends of the branches; it is dioecious, with separate male and female plants.
The fruit is a small red drupe, turning blue when ripe, containing a single seed.
II. How to Grow and Care
Sunlight
Planting your tree in a spot that receives full sun will ensure its at its healthiest and let it grow at a steady rate while producing an ample amount of its attractive fruit. You will notice a marked fall back in growth if it is planted in shadier conditions.
Temperature and Humidity
Chinese pistache trees grow better in warmer, arid climates than in colder regions. If growing in an area that experiences cold weather, try to plant Chinese pistache trees in an area that shelters them from the wind. Typically these trees do not tolerate cold weather beyond light freezing temperatures.
Watering
As a drought-tolerant tree, the Chinese pistache does not require consistent watering after establishing its roots. Water deeply when the soil is dry for the first year. This tree prefers to have only partially wet feet. Young Chinese pistache trees can be gangly and take a while to develop their attractive umbrella shape. The tree needs about two years to develop a proper root system to become strong. Mulching can help the tree retain its moisture. You should water more often in regions that do not get at least one gallon of rainwater per inch of trunk diameter.
Soil
The Chinese pistache grows in almost any well-drained soil, whether loamy, sandy, or clay. It’s adaptable in most soil conditions and pH levels as long as it is moist and rich in organic material.
Fertilizing
Already a fast growing tree, you should not see much a need to give your tree fertilizer. If your Chinese pistache seems to be lagging a bit in its growth, first test the soil to determine what, if any, nutrient deficiencies are present in your soil and then apply a fertilizer with the proper NPK formulation to fix the issue.
Pruning
To help young Chinese pistache trees develop and attractive shape, prune the canopy in January or February to help create the umbrella-like form. After the trees reach over six feet in height, pruning the tree tops can help keep the tree healthy. Prune away excess branches while maintaining the trunk to encourage new, symmetrical growth. When developing the single trunk and selecting from the lateral branches, it might take a few years to train the tree into a sightly shape. When foliage or fruit drops, remove the debris with a rake around the tree to prevent unwanted seedlings. Otherwise, remove dead or diseased branches whenever necessary.
Propagation
Depending on the variety, if the Chinese pistache tree is trademarked or patented, it cannot be propagated. If it is not a protected variety from infringement copyrights, stem cuttings are the best way to propagate. Here’s how:
- Select a soft, green stem long enough that leaf nodes are still attached—about four to six inches. Use a sharp knife or pruning shears to cut below the leaf node and gently remove the leaves on the lower portion of the cutting.
- Dip the stem cuttings into a rooting hormone.
- Fill a container with potting soil and use your finger or a pencil to create small holes.
- Place the stem cuttings in the pencil-shaped holes about two inches in the soil. Press the soil around the stems so they stand upright, and there is no air between the branch and potting mixture.
- Water the stem cuttings in the container. Ensure proper irrigation in the container, so the soil stays moist but well-drained. Place the container in bright, indirect sunlight. Continue watering when the soil is dry—use your fingers to determine.
- Stem cuttings should develop roots within two to three months when you can transplant them outdoors.
How to Grow from Seed
- Start by placing moist peat moss in an envelope with Chinese pistache seeds. Place the envelope in a sealed plastic bag and put it in the refrigerator for 45 days.
- After 45 days, fill a seed starting tray with equal parts peat moss and vermiculite—water, so the soil mixture is moist and well-drained.
- Remove the seeds from the refrigerator and plant them in the seed starting tray about one inch deep.
- Keep the tray in an area that reaches at least 80°F or use a heating mat. Use a spray bottle to keep the soil moist.
- When the seedlings develop a second set of true leaves, transplant them into a small container filled with a soil mixture of equal parts potting soil, peat, and sand.
- After the roots develop, follow the same transplanting process to move them into larger containers.
- After one year of growing in containers, harden off seedlings.
- Transplant the new trees in their permanent locations and water. Dig a hole as deep as the tree’s root ball and three times as wide. Place the tree in the hole and backfill it with soil, so it is level with the top of the root ball.
- Add two or three inches of mulch around the tree, keeping the mulch from touching the trunk. Too much mulch can cause rot bark, encourage pests, and cause roots to grow above the soil level. Spread the mulch evenly, extending as far as the sapling’s branches.
Pests and Diseases
Luckily the Chinese pistache is, for the most part, free from serious pests and disease. One disease that occasionally infects the tree is Verticillium wilt. If your area is known to harbor the fungus or you have had issues with it in your garden, you might consider another tree as there is no cure for this nasty disease, and prevention is the best course of action. You can help prevent it by properly cleaning your garden tools with Lysol, bleach, or alcohol solutions.
Overwintering
Chinese pistache trees do not require over-winter care as they will lose their leaves when cold weather arrives. Deep-green foliage will return when the weather warms, typically around March. This quick-growing tree is consistently developing a spectacular fall colored-foliage of scarlet, orange, and yellow.
III. Uses and Benefits
It is a popular choice for street trees in urban settings because it is very drought tolerant and can survive harsh environments. It is also used as an understock for Pistacia vera. In China, the oil from the seeds is used for biodiesel production. The wood is used for production of furniture, and yields a yellow dye.
It is also used in classical Chinese garden design.