Overview of Crataegus flabellata
Crataegus flabellata, also known as Japanese hawthorn, is a species of thorny shrub or small tree in the Rosaceae family. This plant is indigenous to eastern Asia, including Japan, Korea, and China. It is commonly grown as an ornamental plant in gardens and parks worldwide.
General Appearance of Crataegus flabellata
Crataegus flabellata is an evergreen or deciduous shrub that can grow up to 10 meters tall. It has a round or oblong crown, with densely branched stems and thorns. Its leaves are oval or spatula-shaped, dark green and glossy on top, and pale and hairy underneath.
The plant blooms in late spring or early summer, producing white or pink flowers that grow in clusters. Its fruits are red or purple pomes that ripen in autumn and persist into winter.
Common Names of Crataegus flabellata
Crataegus flabellata has several common names, including Japanese hawthorn, fan-shaped hawthorn, and ???? (Huo Chui Kong Que) in Chinese.
Uses of Crataegus flabellata
Crataegus flabellata has many uses in traditional medicine. Its fruit and leaves have been used in China as a traditional remedy for cardiovascular diseases such as hypertension, coronary heart disease, and angina pectoris. Its fruit contains compounds that have antioxidant properties, which are beneficial for human health.
The wood of Crataegus flabellata is dense, hard, and durable, and has been used in Japan for making tool handles, furniture, and various crafts.
Light Requirements
Crataegus flabellata prefers full sun to partial shade, with at least 6 hours of direct sunlight per day. It can tolerate some shade, but too much shade can weaken the plant and decrease its flowering potential.
Temperature Requirements
Crataegus flabellata is native to temperate regions, and it can tolerate a wide range of temperatures. However, it prefers cool to moderate temperatures and is not well-adapted to hot, dry conditions. In general, it requires a minimum temperature of around 10°C (50°F) to grow well, and can tolerate temperatures as low as -30°C (-22°F) in winter.
Soil Requirements
Crataegus flabellata is adaptable to a wide range of soil types, but it prefers well-draining soils that are rich in organic matter. It can tolerate slightly acidic to slightly alkaline soils (pH 6.0-8.0), but it does best in neutral to slightly acidic soils (pH 6.5-7.5). The plant is quite tolerant of drought and can survive in soils with low moisture content, but it grows best in moist soils that are not waterlogged.
Cultivation Methods
Crataegus flabellata, commonly known as fan-leaf hawthorn, is a small tree or shrub that can grow to a height of up to 5 meters. The plant prefers to be grown in well-drained soil with a pH range of 6.5 to 7.5. It can tolerate a range of soil types, including clay, loam, and sandy soils. The plant prefers full sun but can also tolerate partial shade.
Propagation of the plant can be done either by seed or through cuttings. Seeds are sown in pots or seed trays in the spring, while cuttings are taken in the early summer. In both cases, the plant needs to be kept in a warm and moist environment until they establish roots. Transplanting should be done in the fall, after the last frost.
Watering Needs
Crataegus flabellata should be watered regularly during the growing season, especially in the first year after transplantation. The soil should be kept moist, but not waterlogged. During hot and dry spells, the plant should be watered more often. Mulching can also help retain soil moisture and reduce water loss through evaporation.
Fertilization
Crataegus flabellata is not a heavy feeder and does not require frequent fertilization. A slow-release fertilizer can be applied in the spring, just before new growth begins. Do not apply fertilizer after mid-summer as it can promote late-season growth that may not have time to harden before winter. Compost can also be added to the soil in the fall to provide nutrients for the following year.
Pruning
Pruning of Crataegus flabellata can be done in the early spring, before new growth begins. Dead, damaged, or diseased branches should be removed as soon as they are detected. Unwanted branches can also be removed to control the size and shape of the plant. When pruning, it is recommended to use clean and sharp tools to prevent tearing or damaging the bark. Thinning the branches can also improve air circulation and light penetration, promoting healthy growth.
Propagation of Crataegus flabellata
Crataegus flabellata, commonly known as fan-leaf hawthorn, can be propagated through various methods including seeds, cuttings, and grafting.
Seed propagation
The easiest way to propagate Crataegus flabellata is through seeds. The best time to collect the seeds is during fall when they are ripe and have turned a deep red or brown color. After collecting the seeds, they should be stratified for at least 90 days before sowing. Stratification is the process of exposing the seeds to cold temperatures to break their dormancy.
Once the stratification period is over, the seeds can be sown in a well-draining soil mix. The seeds should be covered with a thin layer of soil and kept moist. Germination usually takes 4-6 weeks.
Cutting propagation
Crataegus flabellata can also be propagated through cuttings. Semi-hardwood cuttings taken during the summer have the highest success rate. Cuttings should be taken from healthy, disease-free plants and should be about 10-15 cm long.
After taking the cuttings, remove the lower leaves and dip the cut end in rooting hormone. Place the cuttings in a well-draining soil mix and keep them in a humid environment. Water the cuttings regularly and wait for roots to develop. This process takes about 6-8 weeks.
Grafting propagation
Grafting is a technique used to reproduce plants with desirable traits. Crataegus flabellata can be grafted onto rootstock from related hawthorn species. The best time to graft is during spring when the sap is rising.
The scion (a piece of the desired plant) is grafted onto the rootstock using a technique called whip grafting. After grafting, the plant should be kept in a humid environment until the graft union has healed. This process takes about 2-3 weeks. Once the graft is successful, the plant can be transplanted into the ground.
Disease Management
One common disease that affects Crataegus flabellata is fire blight. This bacterial disease can cause wilting and blackening of leaves, twigs, and branches. To manage fire blight, it is essential to remove infected plant parts and maintain good sanitation practices in the garden. Fungicides can also be used for prevention and management of the disease.
Cedar hawthorn rust is another fungal disease that affects Crataegus flabellata. This disease can cause yellow spots on leaves, and the berries may also become deformed. To manage cedar hawthorn rust, it is important to reduce the humidity around the plant and to remove infected plant parts. Fungicides can also be used.
Pest Management
The most common pest that affects Crataegus flabellata is the hawthorn lace bug. They feed on the undersides of the leaves and can cause yellowing and browning of leaves. To manage the hawthorn lace bug, it is important to regularly inspect the plant and remove any infested leaves. Insecticidal soap or horticultural oils can also be used.
Another pest that can affect Crataegus flabellata is the apple maggot. This pest can cause damage to the fruit and make it inedible. To manage the apple maggot, it is important to remove any fallen fruit and to use sticky traps to catch the adult flies. Pesticides can also be used, but they must be used according to the instructions.
