Origin
Pittosporum acuminatum Mann var. waimeanum Sherff, also known as Waimea Valley Pittosporum, is a tree species endemic to Hawaii. It is commonly found in the Waianae Range and Koolau Range on Oahu Island.
Common Names
Aside from Waimea Valley Pittosporum, this plant is also known locally as "hoawa," "hoiwa," or "waiwi."
Uses
The Waimea Valley Pittosporum is mainly used for ornamental purposes, particularly in gardens and landscaping because of its beautiful foliage and fragrant flowers. Its wood, on the other hand, is sometimes used for carving.
General Appearance
The Waimea Valley Pittosporum is a small to medium-sized tree that can grow up to 30 feet tall. Its trunk has a dark, rough, and fissured bark, while its branches appear alternating and crooked. Its leaves are evergreen, leathery, glossy, and oblong-shaped, with pointed tips and wavy edges. Each leaf can grow up to six inches long. The plant produces yellow-green flowers that are fragrant and have a sweet scent, which later form into woody capsules filled with seeds.
Light Requirements
The Pittosporum acuminatum Mann var. waimeanum Sherff requires full sun exposure to partial shade. It can grow well in both conditions.
Temperature Conditions
These plants are suitable to grow in warm temperatures, with average temperatures ranging between 60-85°F. They can grow in relatively lower temperatures if they are not below 40°F. However, frost is not suitable for its growth, and it can affect its health.
Soil Requirements
The soil must be well-draining and must be nutrient-rich for healthy plant growth. Acidic to slightly alkaline sandy loam soils are suitable for these plants, and the soil pH should range between 5.6-7.5. If the soil lacks nutrients, then amending the soil with organic fertilizers or compost can be helpful.
Cultivation
Pittosporum acuminatum Mann var. waimeanum Sherff, commonly known as Hawaiian Cheesewood, is a slow-growing shrub that can reach a height of eight to twelve feet and can spread to a width of ten feet. The plant requires filtered sunlight and grows well in well-drained, slightly acidic soil with a pH range of 5.5 to 6.5. It can tolerate windy conditions but may require support in areas with strong winds. It is a drought-tolerant plant that thrives in areas with low to moderate rainfall.
Watering Needs
Hawaiian Cheesewood requires deep and infrequent watering, especially during the summer months. It is important to ensure that the soil is moist but not waterlogged. Overwatering can lead to root rot, which can be fatal to the plant. The use of mulch can help to retain moisture and reduce evaporation.
Fertilization
You can fertilize Hawaiian Cheesewood with an all-purpose fertilizer once a year during the spring. Fertilizers with balanced nitrogen, phosphorus, and potassium ratios are ideal for this plant. It is important to avoid over-fertilization, which can lead to an excess of nitrogen, resulting in weak growth and susceptibility to pests and diseases.
Pruning
Pruning helps to maintain the shape and size of the plant. You can prune the plant during the winter months when the plant is dormant. Prune the higher branches to allow more sunlight, and air to reach the lower section. You should remove the dead and damaged wood immediately. In addition, removing the lower branches can encourage vertical growth and improve air circulation.
Propagation of Pittosporum acuminatum Mann var. waimeanum Sherff
Pittosporum acuminatum Mann var. waimeanum Sherff, commonly known as Hawaiian cheesewood, is a slow-growing evergreen plant that can reach up to 20 feet in height. It is a popular ornamental plant in tropical and subtropical regions due to its glossy green leaves and small fragrant flowers.
Propagation by Seeds
The most common method of propagation for Pittosporum acuminatum Mann var. waimeanum Sherff is by seeds. The plant produces small, papery capsules that contain numerous tiny seeds. The seeds can be collected from the mature capsule, cleaned, and stored for later use.
To propagate the plant from seeds, the seeds are sowed in a well-draining potting mix that is kept moist until germination. It is important to keep the seeds out of direct sunlight until they germinate. The seedlings can be transplanted into larger pots or directly into the ground once they have developed a few leaves and are sturdy enough to handle.
Propagation by Cuttings
Pittosporum acuminatum Mann var. waimeanum Sherff can also be propagated by cuttings. This method is usually used to create clones of a specific variety of the plant. Hardwood cuttings taken during the winter months typically root better than softwood cuttings taken during the summer months.
The cuttings should be taken from healthy plants that are free of pests and diseases. The cuttings should be 4-6 inches long and taken from the current season's growth. The lower leaves should be removed, and the cutting should be dipped in rooting hormone before being placed in a well-draining potting mix. The cuttings should be kept moist until new growth appears, and then they can be transplanted into larger pots or directly into the ground.
Propagation by Air Layering
Air layering is another method of propagation for Pittosporum acuminatum Mann var. waimeanum Sherff. This method involves creating a wound on a mature stem and encouraging the plant to produce roots at the wound site. Once the roots have formed, the stem can be cut off and transplanted.
To air layer the plant, select a healthy vigorous stem with a diameter of at least half an inch. Create a 1-2 inch wound on the stem by scraping off the bark and the cambium layer. Wrap the wound with moist sphagnum moss, and then wrap the moss with plastic wrap to keep it moist. After a few months, roots should appear at the wound site. Cut off the rooted stem below the wound and transplant it into a pot or directly into the ground.
It is important to keep the newly propagated plant well-watered and protected from direct sunlight until it has established itself.
Disease and Pest Management for Pittosporum acuminatum Mann var. waimeanum Sherff
Pittosporum acuminatum Mann var. waimeanum Sherff, commonly known as Hawaiian cheesewood or velvet-leaf pittosporum, is a plant native to Hawaii. As with any plant, it is susceptible to a number of diseases and pests that can impact its health and appearance. Here are some common problems and ways to manage them:
Diseases
Leaf spot: Leaf spot is a fungal disease that can cause brown or black spots on the leaves. To manage this disease, remove infected leaves and debris from around the plant. Ensure that the plant has adequate air circulation and avoid watering in the evening as this can promote fungal growth. If the problem persists, consider using a fungicide according to the product label.
Root rot: Root rot is a fungal infection that can cause the plant to wilt and die. To prevent root rot, ensure that the soil is well-draining and avoid overwatering. If the plant has already been infected, remove it from the soil and dispose of it. Allow the soil to dry out before replanting.
Pests
Mealybugs: Mealybugs are small, white, cotton-like insects that feed on the sap of the plant. They can cause stunted growth, yellowing leaves, and eventually death if left untreated. To manage mealybugs, use a cotton swab dipped in rubbing alcohol to remove them from the plant. Alternatively, use a pesticide formulated for mealybugs according to the product label.
Aphids: Aphids are tiny, pear-shaped insects that can cause distorted leaves and stunted growth. To manage aphids, wash the plant with a strong stream of water from a hose to dislodge them. Alternatively, use a pesticide formulated for aphids according to the product label.
Scale insects: Scale insects are small, oval-shaped insects that can cause yellowing leaves and a sticky residue on the plant. To manage scale insects, scrape them off the plant with a small brush or toothbrush. Alternatively, use a pesticide formulated for scale insects according to the product label.
By monitoring your Pittosporum acuminatum Mann var. waimeanum Sherff for signs of disease and pests and taking action when necessary, you can help ensure that your plant remains healthy and beautiful.
