Overview of Crataegus ×whittakeri Sarg.
Crataegus ×whittakeri Sarg. is a rare flowering plant with a deciduous shrub and belongs to the family Rosaceae. It is a hybrid of two other species of the Crataegus genus, namely Crataegus laevigata and Crataegus monogyna. The plant is commonly known by the name of Whittaker's hawthorn in honor of the botanist who discovered it. The plant was first brought to attention in 1910 and gained importance among horticulturists.
Origins and Common Names
The Crataegus x whittakeri Sarg. is a hybrid plant that was initially created through artificial hybridization of two species, Crataegus laevigata and Crataegus monogyna, which belong to the subfamily Maloideae. This rare plant is predominantly found in the United Kingdom, where it is commonly known as the Whittaker's hawthorn.
Appearance
The Crataegus ×whittakeri Sarg. is an elegant deciduous shrub with an upright, spreading shape that can attain a height of between 3 and 8 meters. The plant has small thorns that grow along its stems. The bark of these shrubs is smooth and grayish-brown in color. During spring, the plant showcases striking clusters of white-scented flowers. The foliage of the Whittaker's hawthorn is a deep green color with a glossy and highly serrated surface. In autumn, the leaves turn to a vibrant red color, producing a stunning display of colors.
Uses
The Crataegus ×whittakeri Sarg. is primarily used as an ornamental plant that adds a touch of elegance and beauty to landscapes and gardens. Its stunning display of vibrant colors during autumn adds life to any garden. The plant grows best in full sun or partial shade and thrives in moist soil conditions, making it an excellent choice for erosion control and habitat restoration projects. The fruits of the Whittaker's hawthorn plant are also edible and are gathered to make jams, jellies, and some alcoholic beverages.
Light Requirements
Crataegus ×whittakeri Sarg. is a sun-loving plant and requires full sunlight to grow properly. The plant requires at least 6-8 hours of direct sunlight per day. The plant can tolerate some shade, but it must be positioned in an area where it receives ample amounts of sunlight.
Temperature Requirements
Crataegus ×whittakeri Sarg. requires moderately cool temperatures to grow properly. The plant can tolerate a wide range of temperature, but the ideal temperature range for this plant is between 10°C to 28°C. The plant can tolerate cold temperatures but may not survive extreme cold conditions.
Soil Requirements
The plant requires well-drained soil to grow properly. The soil should be moderately fertile, and the pH range should be between 6.0 to 7.0. The plant can tolerate a wide range of soil types, but it prefers slightly acidic soils. It is recommended to add organic matter to the soil before planting as it will improve soil quality and help the plant to grow better. Additionally, the plant prefers soils that are rich in nutrients and have good drainage capacity.
Cultivation
Crataegus ×whittakeri Sarg. is a small deciduous tree that is easy to grow and maintain, making it a popular choice for home gardeners. To cultivate this plant, select a sunny spot in your garden with well-draining soil. The plant can tolerate a wide range of soils, from acidic to alkaline, but prefers a slightly acidic soil with a pH range of 6.0-6.5. Prepare the soil by adding compost or organic matter and loosen it to a depth of at least 12-15 inches.
Plant the young tree in early spring or fall, making sure to dig a hole twice as wide as the root ball. Set the tree in the hole so the top of its root ball sits level with the soil surface. Water the tree immediately after planting and apply a layer of mulch around the base to retain moisture and control weeds.
Watering Needs
Crataegus ×whittakeri Sarg. requires consistent moisture for its first year, especially during dry spells, to encourage root development. Once established, the plant is fairly drought-tolerant but still requires regular watering for optimal growth and production. Water the plant deeply, at least 1 inch per week, and more during hot, dry weather. Avoid overwatering, as this can lead to root rot and other fungal diseases.
Fertilization
Fertilization is not usually necessary for this plant, as it can thrive in most soils. However, if you wish to provide additional nutrients, apply a balanced fertilizer in early spring. Use a slow-release fertilizer or a liquid fertilizer diluted to half strength. Avoid fertilizing after mid-summer, as this can encourage late-season growth that may not harden off before winter and become damaged.
Pruning
Pruning is important to maintain the shape and size of the tree and to promote strong, healthy growth. Prune the plant in late winter or early spring while it is still dormant, before new growth appears. Remove any dead, diseased, or damaged wood, as well as any crossing or rubbing branches. Thin out congested branches to improve air circulation and reduce the risk of fungal infections. Avoid pruning heavily in the first few years after planting, as this can stunt growth and delay fruit development.
Propagation of Crataegus ×whittakeri Sarg.
Crataegus ×whittakeri Sarg. can be propagated by two main methods: seed propagation and vegetative propagation.
Seed Propagation
Seed propagation is the most common method of propagating Crataegus ×whittakeri Sarg. The seeds are collected in the late summer or early fall and should be sown immediately after collection. The seeds require a period of cold stratification to break dormancy. This can be achieved by either planting the seeds directly in the ground in the fall or placing the seeds in a moistened medium and storing them in a cool place for several months before planting in the spring. Seeds usually germinate within several weeks after planting.
Vegetative Propagation
Vegetative propagation of Crataegus ×whittakeri Sarg. can be done by several methods, including grafting, budding, and cuttings.
Grafting is the most common vegetative propagation method. It involves joining a scion, which is a piece of stem with buds or branches, to a rootstock. The scion should be taken from the desired cultivar or plant, and the rootstock should be a suitable Crataegus species or rootstock. The two pieces are then joined securely, and the graft union is wrapped with grafting tape to hold everything in place until the graft takes.
Budding is a type of grafting that involves inserting a bud from the desired plant into the bark of the rootstock. This method is typically done in the summer when the bark is slipping and requires more skill than regular grafting.
Cuttings are also a viable option for propagating Crataegus ×whittakeri Sarg. This method involves taking a stem cutting from the desired plant and rooting it in a moistened medium. Hardwood cuttings are typically taken in the winter when the plant is dormant, and softwood cuttings are taken in the spring or early summer when the plant is actively growing.
Disease and Pest Management for Crataegus ×whittakeri Sarg.
Crataegus ×whittakeri Sarg., also known as the Whittaker's hawthorn, is a small deciduous tree that can be affected by various diseases and pests. Here are some of the common ones and suggested ways to manage them:
Diseases
Cedar-Quince Rust: This disease appears as yellow spots on the leaves, which eventually turns brown with black spots in the center. The disease can cause defoliation in severe cases. It can be managed by removing the alternate hosts such as cedar and juniper and by avoiding planting hawthorns near them. Fungicides can also be used as a preventive measure.
Fire Blight: This bacterial disease can cause cankers on the branches and stems, and the leaves turn brown and wilt. The disease can be managed by pruning infected branches and using bactericides during early spring.
Leaf Spot: This fungal disease causes brown spots on the leaves. It can be managed by removing infected leaves and using fungicides.
Pests
Aphids: These small insects suck the sap from the leaves and can cause deformation and curling of the leaves. They can be managed by using insecticidal soap or neem oil.
Caterpillars: The larvae of hawthorn leaf miners and tent caterpillars can cause defoliation by eating the leaves. They can be managed by using Bacillus thuringiensis (Bt) or by handpicking and removing the larvae.
Scales: These insects can cause yellowing and stunted growth of the leaves by feeding on the sap. They can be managed by using horticultural oil or insecticidal soap.
Regular monitoring and prompt action can prevent the spread of diseases and pests and help maintain the health of Crataegus ×whittakeri Sarg.
