Overview
Malus glabrata Rehd., also known as M. toringoides, is a deciduous tree species belonging to the Rosaceae family. Its native range is in China and Taiwan but is now cultivated in other countries as ornamental trees.
Common Names
The common names of Malus glabrata Rehd. include torinomenoki in Japanese, shan che in Chinese, and Taiwanese crab apple or Formosan apple.
Description
Malus glabrata Rehd. is a small to medium-sized tree that can grow up to 25 ft. in height. It has an open, rounded crown with a trunk that is covered with grayish-brown, scaly bark. The leaves are elliptic to obovate, with serrated edges, and have a dark green color that turns yellow-orange in the fall. The flowers are white or pinkish and bloom in clusters in the spring. The fruit is a small, red, or yellowish-green apple that is sour and inedible.
Uses
Malus glabrata Rehd. is grown mainly as an ornamental tree for its attractive foliage, showy flowers, and abundant fruit. Its wood is also used for making small decorative objects. In traditional Chinese medicine, the bark and fruits of the tree are used to treat diarrhea, dysentery, inflammation, and fever. It is also used as a natural insecticide and pesticide, and the fruit is a source of pectin for making jams and jellies.
Light requirements
Malus glabrata Rehd. is a plant species that requires a lot of sunlight to grow well. It prefers full sun exposure and cannot thrive in shaded areas. Therefore, it is recommended to grow this plant in open areas where it is exposed to direct sunlight.
Temperature requirements
This plant species thrives well in areas that have a cool climate. It prefers temperatures between 5°C and 25°C. At high temperatures, Malus glabrata Rehd. experiences drought stress, which affects its growth and development. Therefore, it is recommended to grow this plant species at temperatures within its range of preference.
Soil requirements
Malus glabrata Rehd. requires well-draining soil that is fertile and rich in organic matter. The soil should have a pH ranging from 5.5 to 7.5. It cannot thrive in poorly drained soils, and it is adversely affected by waterlogging. When planting Malus glabrata Rehd., it is recommended to mix the soil with organic matter such as compost to improve the soil structure and nutrient content. Additionally, applying mulch around the base of the plant helps to retain moisture, suppress weed growth, and avoid soil erosion.
Cultivation Methods
The plant Malus glabrata Rehd. is a deciduous shrub that requires full sunlight for growth and development. It grows well in moist, well-drained soil that is rich in organic matter. Before planting, loosen the soil to a depth of about 12 inches and remove any weeds or rocks. Plant the shrub at the same depth as its previous location plant, and make sure to provide adequate spacing between plants. The ideal time for planting this shrub is during the early spring season.
Watering Needs
Malus glabrata Rehd. requires regular watering during the growing season. Watering should be done when the soil is dry to a depth of about 1 inch. Use a soaker hose or drip irrigation to water the shrub deeply and avoid getting the foliage wet. Watering should be reduced in the fall when the plant begins to lose its leaves, and it should be stopped entirely in the winter season when the plant goes dormant.
Fertilization
Fertilization is a crucial aspect of caring for Malus glabrata Rehd. shrub. Apply a balanced fertilizer (10-10-10) in the early spring season to encourage healthy growth and development. Repeat the fertilization every year in the spring season. If the soil is deficient in any specific nutrients, you may use a fertilizer that is rich in that specific nutrient. Always follow the manufacturer's instructions when applying fertilizer to avoid overfertilizing.
Pruning
Pruning is another essential aspect of caring for a Malus glabrata Rehd. shrub. Prune the plant in the early spring season before new growth appears. Remove any dead, damaged, or diseased branches. Also, remove any crossing or rubbing branches to improve airflow in the shrub. If the shrub is too tall, prune it to the desired height. Avoid pruning in the fall season or winter when the shrub is dormant.
Propagation methods for Malus glabrata Rehd.
Malus glabrata Rehd. is propagated through both sexual (seed) and asexual (vegetative) methods.
Sexual propagation through seeds
Seeds of Malus glabrata Rehd. can be collected from mature fruits. The seeds need to go through stratification (exposure to cold and moist conditions) for a certain period to break their dormancy before being sowed. In general, seeds are mixed with moist peat moss or vermiculite and stored in a fridge or cold room for several weeks. After stratification, the seeds can be sowed in a well-draining soil mix. The seedlings will emerge in a few weeks under suitable conditions. Seed propagation may result in variability in the offspring due to genetic recombination.
Asexual propagation through cuttings
Malus glabrata Rehd. can be propagated through cuttings as well. The best time for taking cuttings is during the dormant season (late winter to early spring). Semi-hardwood cuttings of about 10 cm long are taken from the previous season's growth. The leaves on the lower half of the cutting are removed, and the stem's base is treated with rooting hormone powder before inserting it into a pot filled with moist, well-draining soil mix. The pot is covered with a clear plastic bag to maintain high humidity and placed in a shaded area. The cutting should develop roots in six to eight weeks and be ready to transplant into a bigger pot or garden bed. Asexual propagation maintains the genetic characteristics of the parent plant.
Disease Management
Malus glabrata, commonly known as the hairy crabapple, is susceptible to various diseases. One of the most common diseases that affect the plant is apple scab. Apple scab causes dark spots on the leaves, which eventually turn yellow and fall off. It can also affect the fruit, causing black lesions on the skin. To manage apple scab, it is best to keep the area around the plant clean by removing fallen debris and leaves. Regularly spraying the plant with fungicides such as copper or sulfur can also help manage this disease.
Fire blight is another disease that can affect the hairy crabapple. This bacterial disease causes the infection to appear as blackened and wilted shoots. The best way to manage fire blight is to prune the affected areas of the plant as soon as possible to avoid spreading the infection. It is also advisable to spray the plant with antibiotics or copper-based fungicides to prevent further spread of the disease.
Pest Management
In addition to diseases, various pests can also affect the hairy crabapple. One of the most common pests is the codling moth. The codling moth is a caterpillar that feeds on the fruit, causing the fruit to fall prematurely and can allow for secondary infections. It is best to use pheromone traps or insecticides to manage these pests.
Another pest that can affect the hairy crabapple is the aphid. Aphids feed on the plant's sap, causing the leaves to yellow or curl. To manage aphids, it is best to use insecticidal soap or neem oil and prune any affected areas of the plant. Encouraging the presence of natural predators such as ladybugs can also help manage the aphid population.
