Origin
Melicope quadrangularis (St. John & Hume) T.G. Hartley & B.C. Stone, also known as Alani in Hawaii, belongs to the Rutaceae family and is native to the Pacific region, including Hawaii, Samoa, and Tonga Islands.
Common Names
Aside from Alani, other common names for Melicope quadrangularis include Four-Angled Pelea, Hangehange, Hangehange Kouka, and Swamp Pelea.
Uses
Melicope quadrangularis has been traditionally used in the Pacific region for its medicinal properties. Its bark, leaves, flowers, and roots have been used as a pain reliever, antitussive, and stomach ailments treatment. Additionally, the bark has been applied topically to heal wounds and help with rheumatism and neuralgia. Nowadays, Melicope quadrangularis is also used as an ornamental plant, and it is commonly grown in gardens and parks due to its pleasant fragrance and attractive appearance.
General Appearance
Melicope quadrangularis is a small evergreen tree that can reach up to 10 meters in height. It features a slender trunk, and its branches grow at a right angle to each other, giving it a quadrangular appearance. Its leaves are dark green, glossy, and leathery, with an oblong to elliptical shape, measuring between 10 to 20 cm in length. The tree bears clusters of fragrant flowers, which can range from white to pale pink in color. Its fruit is a small round drupe, measuring up to 1 cm in diameter, with a purplish-black color when ripe.
Light Requirements
Melicope quadrangularis thrives in bright but indirect light. It prefers a location that receives about six to eight hours of sunlight per day. Direct sunlight may scorch its leaves, so it is best to provide some shade during the hottest part of the day.
Temperature Requirements
This plant prefers a warm and humid environment. It does well in temperatures between 65 to 80 degrees Fahrenheit. Temperatures below 60 degrees can cause the plant to wilt and drop its leaves. It is important to maintain a constant temperature to prevent plant stress.
Soil Requirements
Melicope quadrangularis prefers a well-draining soil that is rich in organic matter. A mixture of peat moss, perlite, and sand is an ideal growing medium. The soil should have a pH range of 6.0 to 7.5. Additionally, this plant requires regular fertilization to ensure healthy growth. A balanced fertilizer that contains equal amounts of nitrogen, phosphorus, and potassium is recommended.
Cultivation
Melicope quadrangularis, also known as ‘Alani’ in Hawaii, is a species of flowering tree that belongs to the citrus family. It typically grows in tropical and subtropical regions and requires full sunlight to thrive. The plant can be grown from seeds or stem cuttings.
If growing from seeds, it is best to soak them in warm water for 24 to 48 hours before planting. Sow the seeds in well-draining soil and keep them moist until they germinate. The ideal temperature range for germination is between 70 and 80°F.
If propagating from stem cuttings, select a healthy stem and cut it at a 45-degree angle. Dip the cut end in rooting hormone and plant it in a container filled with well-draining soil. Keep the soil moist and place the container in an area with bright, indirect light. Rooting should occur within four to six weeks.
Watering Needs
Melicope quadrangularis prefers consistently moist soil but avoid overwatering. It is essential to allow the soil to dry slightly between watering to prevent the tree from developing root rot. During hot summer months, the plant may require more frequent watering.
It is crucial to ensure that the container or soil has proper drainage as the plant cannot tolerate standing water around its roots. If the plant is grown in a container, the soil should be allowed to dry completely before watering again.
Fertilization
During active growth, Melicope quadrangularis requires regular fertilization with a balanced, slow-release fertilizer. Fertilize the plant every three to four months, starting in early spring and stopping by late summer. Too much nitrogen can cause the plant's growth to be too vigorous and increase susceptibility to pests and diseases.
It is also beneficial to use organic compost and manure to improve soil fertility and structure. However, avoid using fresh manure as it can burn the roots and damage the plant.
Pruning
Melicope quadrangularis requires minimal pruning; however, periodic pruning will help to maintain its shape and size. The plant can be pruned after the blooming period, typically in late spring or early summer.
The general rule of thumb is to remove up to one-third of the tree's oldest branches while leaving several new shoots to encourage proper growth and plant health. Prune any damaged, infected, or dead branches as soon as they are observed.
Propagation of Melicope quadrangularis
Melicope quadrangularis, commonly known as the bumpy kahului tree, is a tropical plant native to Hawaii. It can be propagated through various methods.
Propagation through Cuttings
One of the easiest ways to propagate Melicope quadrangularis is through cuttings. Select a healthy branch that is at least 6 inches long and has a few nodes. Remove the leaves from the lower half of the stem and dip the cut end into a rooting hormone. Plant the cutting in a well-draining soil mix and water it well. Keep the pot in a warm, bright location, and mist the cutting regularly. Roots should develop within a few weeks, and you can transplant the new cutting into its permanent location.
Propagation through Seeds
Melicope quadrangularis can also be propagated through seeds. The seeds can be collected from the plant when they turn brown and start to fall off. Sow the seeds in a well-draining soil mix, and keep the soil moist. Germination can take anywhere from a few weeks to several months, depending on the conditions. Once the seedlings are several inches tall, you can transplant them into individual pots or directly into the ground.
Propagation through Air Layering
Air layering is another propagation method that can be used for Melicope quadrangularis. Select a healthy branch that is at least 1 inch in diameter and score the bark halfway through the branch about 6 inches from the tip. Apply rooting hormone to the wound and wrap it with damp sphagnum moss and plastic wrap. Keep the moss moist and wait several months for roots to develop. Once roots have developed, detach the new plant from the main plant and pot it up.
Disease Management
Melicope quadrangularis, also known as "p?nini o Hawai‘i," is generally a hardy plant that is not prone to many serious diseases. However, there are a few diseases that can harm the plant. One potential disease is anthracnose, which causes dark, sunken lesions on leaves, stems, and fruit. To manage anthracnose, it is recommended to remove infected plant debris, ensure adequate spacing between plants for air circulation, and use a fungicide if necessary.
Another disease that can affect Melicope quadrangularis is powdery mildew, which forms a white, powdery coating on leaves, stems, and flowers. To manage powdery mildew, it is recommended to remove infected plant parts, improve air circulation, and use a fungicide if necessary. Additionally, it is important to avoid overhead watering, which can encourage the growth of powdery mildew.
Pest Management
Melicope quadrangularis is generally not heavily infested by pests, but there are a few that may cause damage. One pest that can cause problems is the spider mite, which sucks the sap out of the plant, causing stunted growth, yellowing leaves, and webbing. To control spider mites, it is recommended to spray the plant with water to knock off the mites, prune infested leaves, and use an insecticidal soap or miticide.
Another pest that can affect Melicope quadrangularis is the scale insect, which sucks on the plant's sap and excretes a sticky substance that can cause sooty mold to grow. This can result in stunted growth, yellowing leaves, and eventual plant death. To manage scale insects, it is recommended to prune heavily infested areas, use a horticultural oil or insecticidal soap, and introduce natural predators such as ladybugs and lacewings.
Regular inspection of Melicope quadrangularis and a routine maintenance program can help prevent serious disease or pest outbreaks. Contacting a professional for advice and treatment options can be helpful in the event of a serious infection or infestation.
