Description of Hydrangea arborescens L. var. deamii St. John
Hydrangea arborescens L. var. deamii St. John, commonly known as "Deam's smooth hydrangea," is a deciduous shrub that belongs to the Hydrangeaceae family. This plant is native to the central and eastern regions of North America, particularly in the United States.
Appearance of Hydrangea arborescens L. var. deamii St. John
The Deam's smooth hydrangea generally grows up to three feet tall and three feet wide. Its leaves are oval-shaped with serrated edges, measuring around 3-8 cm long and 2-5 cm wide. The shrub's flowers are white, flat-topped, and cluster at the end of the stems. It blooms from May to July and produces fruit that is a dry, brown capsule.
Uses of Hydrangea arborescens L. var. deamii St. John
Hydrangea arborescens L. var. deamii St. John is an outstanding ornamental shrub that is widely used in gardens and landscapes. It is particularly popular for its attractive white flowers, which are often seen in mass plantings, border, and hedges. Aside from its aesthetic value, Deam's smooth hydrangea is also known for its medicinal properties. It contains a natural compound called hydrangin that is used in traditional medicine to treat urinary tract infections, kidney stones, and other urinary and bladder-related problems.
In conclusion, Hydrangea arborescens L. var. deamii St. John is a beautiful and beneficial plant that adds value to any garden and landscape.
Light Requirements
Hydrangea arborescens L. var. deamii St. John thrives best in partial to full shade. Planting it in areas that receive around four hours of direct sunlight is ideal for growth. Excessive exposure of the plant to sunlight may lead to burnt leaves and stunted growth.
Temperature Requirements
The plant requires mild temperatures and can adapt to a wide range of temperatures once established. The ideal temperature range for the plant is between 60°F to 70°F. Extreme temperatures below 25°F or above 85°F cause damage to the leaves and stem of the plant.
Soil Requirements
Hydrangea arborescens L. var. deamii St. John thrives in slightly acidic soil, ranging between pH 5.2 and 6.5. The soil should be well-draining, fertile, and rich in organic matter. A soil pH above 6.5 may cause iron chlorosis, a condition characterized by yellowing of the leaves. Consistent moisture is essential for the plant's optimum growth; hence, it should be planted in areas with adequate irrigation and drainage.
Cultivation Methods
The Hydrangea arborescens L. var. deamii St. John plant requires well-drained soil that is rich in organic matter and a pH level of 6.0 to 6.5. It can thrive in full to partial sunlight, but it is best to plant them in a location that receives morning sunlight and afternoon shade.
While it can tolerate some drought once established, it is better to keep the soil moist but not water-soggy. You can add a layer of mulch to help retain soil moisture.
Propagation can be done through stem cuttings or by division. Stem cuttings should be taken in the early summer, and the division should be done in the spring or fall.
Watering Needs
Hydrangea arborescens L. var. deamii St. John requires consistent moisture in the soil to perform well. Watering should be done early in the morning or late in the day to avoid water loss through evaporation.
The frequency of watering depends on the climate and soil type. In general, it is better to give a deep watering once a week rather than frequent shallow watering.
Fertilization
Hydrangea arborescens L. var. deamii St. John can benefit from fertilization with a balanced, slow-release fertilizer in the early spring, just after the last frost.
Use a fertilizer that contains balanced quantities of nitrogen, phosphorus, and potassium. You can also supplement with additional nutrients such as iron, magnesium, and sulfur if the soil is deficient in these minerals.
Pruning
Pruning Hydrangea arborescens L. var. deamii St. John can be done in the late winter or early spring.
Remove any dead or damaged wood, and cut back about one-third of the previous year's growth to promote new growth. Be careful not to remove too much, as the plant blooms on new wood.
You can also control the shape and size of the plant through selective pruning. Prune back lateral branches to their second or third node in early summer to encourage fuller growth.
Propagation of Hydrangea arborescens L. var. deamii St. John
Propagation of Hydrangea arborescens L. var. deamii St. John can be achieved through different methods, such as:
Softwood Cuttings
This method is best done during spring. Take cuttings of the new stem growth that are about 4-6 inches long and make a clean cut below a node. Remove the lower leaves and dip the cut ends in rooting hormone. Plant the cuttings in pots filled with a well-draining soil mix and keep them moist. Keep the pots in a warm and bright location, but away from direct sunlight. Roots should develop in about 4-6 weeks.
Division
Hydrangea arborescens L. var. deamii St. John can also be propagated through division. This is best done during the late winter or early spring, just before the plant begins to grow again. Dig up the plant carefully and separate the roots into two or more sections, each containing some stems and roots. Replant the divisions in a suitable location with well-draining soil and keep the soil moist until the new plants have established themselves.
Seeds
Propagation through seeds is also possible, but it may take longer for the plant to grow to flowering maturity, and the resulting plants may not be true to the parent plant if they were hybrid. Collect mature seeds from the plant after flowering and store them in a cool and dry location until spring. Plant the seeds in a well-draining soil mix and keep the soil moist. Germination usually occurs within 2-4 weeks, but the seedlings may take several years to reach flowering maturity.
Disease and Pest Management for Hydrangea arborescens L. var. deamii St. John
Hydrangea arborescens L. var. deamii St. John is a popular shrub that is native to the eastern United States. It is a hardy, low-maintenance plant that thrives in a variety of conditions. However, like all plants, it is vulnerable to disease and pests. Here are some common problems that may affect this plant and tips for managing them.
Common Diseases
Cercospora Leaf Spot: This is a fungal disease that causes brown spots on the plant's leaves. To manage this disease, remove any infected leaves as soon as possible, and avoid overhead watering to prevent the fungus from spreading.
Powdery Mildew: This is a common fungal disease that affects many plants, including hydrangeas. It appears as a white or gray powdery coating on the leaves and stems of the plant. To manage this disease, prune any affected branches and improve air circulation around the plant by spacing it appropriately and removing any crowded vegetation around it.
Phytophthora root rot: This is a fungal disease that attacks the roots of the plant, leading to wilting, yellowing, and eventual death. To manage this disease, improve drainage around the plant, avoid overwatering, and remove any affected plants from the garden.
Common Pests
Aphids: These are small, soft-bodied insects that suck the sap from the plant, causing wilting and yellowing. To manage them, wash them off with a strong stream of water, or use an insecticidal soap.
Spider Mites: These are tiny, eight-legged arachnids that feed on the undersides of the leaves. To manage them, wash them off with a strong stream of water, or use an insecticidal soap or miticide.
Japanese Beetles: These are common garden pests that can skeletonize the leaves of hydrangeas and other plants. To manage them, handpick them off the plant, or use a commercial trap or insecticide.
By following the above steps, you can ensure the health and vitality of your Hydrangea arborescens L. var. deamii St. John plant and keep it free from disease and pests.
