How to Grow and Care for Japanese Flowering Cherry

Japanese flowering cherry trees (Prunus serrulata spp.) are ornamental deciduous trees grown for their beautiful pinkish-red blossoms during the spring months. These fast-growing (1 to 2 feet per year), but short-lived trees are best grown in areas with full sun, loamy and well-drained soil, and temperatures that don't dip below minus 10 degrees Fahrenheit. The leaves, stems, and seeds of cherry trees are toxic to pets and humans, so it's best to plant them away from areas that children and pets frequent.

Japanese Flowering Cherry Care

Here are the main care requirements to keep your Japanese flowering cherry tree growing healthy:

• Plant Japanese flowering cherry trees in the early fall, well before the first frost, to give them time to establish a strong root system before cold winter temperatures.
• Choose a planting site with full sun and loamy, well-drained soil with plenty of humus.
• Back-fill the planting hole with a mix of soil and compost.
• Water often enough to keep the soil evenly moist, as Japanese flowering cherry trees are not drought-tolerant.
• Grow in USDA hardiness zones 5b to 8a to provide the right conditions for winter dormancy.
• Feed annually in the spring with cherry tree fertilizer.

Light

Japanese cherry trees grow best in full sun, which means it needs at least six hours of direct, unfiltered sunlight each day to produce optimal blossoming. However, the tree can also tolerate partial shade.

Soil

This type of cherry tree will tolerate a variety of soil types, but it prefers moist, fertile, well-drained loamy soil with a relatively neutral pH (6.7 to 7.1). Ideal soil will make this plant less susceptible to the many fungal diseases that can plague the species.

Water

Japanese flowering cherry prefers plenty of moisture—at least 1 inch per week. Add a layer of mulch to the top of the soil to keep it moist and insulated, particularly during the winter months. Once well-established, Japanese flowering cherry will tolerate short droughts.

Temperature and Humidity

Japanese cherry trees have been known to survive winter temperatures down to minus 10 degrees Fahrenheit, which means that they can be borderline hardy in the northern part of zone 5. Zones 5b to 8a are ideal climates, as more southern gardens may not provide the 45-degree winter dormancy these trees need.

Prolonged periods of cool, wet, and humid summer weather can be a problem for this species, since it fosters a number of fungi that can create serious disease for cherry trees.

Fertilizer

Feed Japanese cherry trees once a year in the spring with a fertilizer that's specifically developed to be used with cherry trees. To fertilize organically, back-fill withsome compostwhen planting and top-dress periodically thereafter, watering the nutrients into the soil.

Types of Japanese Flowering Cherry

Japanese flowering cherries include cultivars of the Prunus serrulata species, which is likely the result of crossbreeding many wild species. The 'Kanzan' or 'Sekiyama' cultivars are popular choices for home landscapes since they are smaller, tidy, non-fruiting trees with an attractive growth habit.

There are several common award-winning cultivars of P. serrulata, including:

• 'Kanzan': This very popular variety grows up to 30 feet tall and 25 feet wide, with deep pink double blossoms. This is the most popular of all Japanese flowering cherries.
• 'Kiku-shidare': Also known as Cheal's weeping cherry, this cultivar has arching, cascading branches. It grows to 15 feet tall and wide and has rich pink double blossoms.
• 'Fugenzo': This cultivar has beautiful white flowers that gradually turn pink. It grows to 30 feet tall and wide.
• 'Shirotae': With large pure white flowers, this variety grows up to 2 inches across. Growing to a maximum of 20 feet tall with slightly arching branches, it is ideal for small landscapes.
• 'Asano': This cultivar is known for its puffy, full flowers resembling those of chrysanthemums. It grows to 20 tall feet.
  

Pruning

Generally speaking, very little pruning is necessary for Prunus serrulata cultivars other than removing damaged branches. In fact, the more you prune, the more likely you are to allow fungal diseases to take hold.

If you need to prune, do so after the tree flowers. Always sterilize your cutting tools after each cut. Some limbs can grow too quickly and heavy for the base, so it's best to prune away the heavy branches as needed.

Propagating Japanese Flowering Cherry

Most ornamental cherry trees are created by grafting branches from a selected cultivar onto the hardier rootstock of a wild cherry. Propagating them yourself is an uncertain prospect, as the plants resulting when you root stem cuttings will not have the hardy rootstock. The shape, size, and overall vigorousness can be quite different than your parent plant.

Cuttings should be taken from semi-hardwood branches during the summer months. If you wish to experiment with propagating via stem cuttings, here's how to do it:

1. Choose a branch that has two to four leaf nodes and leaves.
2. Using sterilized pruning shears, cut off a 4- to 8-inch section at a horizontal angle and remove the leaves from the bottom two-thirds of the branch.
3. Dip the cutting into rooting hormone.
4. Push the cut end into a mixture of half perlite and half sphagnum peat moss. Pat down the soil around it.
5. Place a loosely secured plastic bag over the container, then move the pot to a sunny location.
6. Mist the cutting twice a day to keep the soil moist.
7. After two to three months, gently tug on the cutting to see if it's rooted. If there's resistance, let the cutting grow until the roots have filled the pot.
8. When ready, transfer the plant to a gallon-sized container filled with potting soil. Move it outside to let it acclimate to the temperatures for a week before transplanting the tree to a location with full sun.

How to Grow Japanese Flowering Cherry From Seed

Most Japanese flowering cherry tree cultivars are sterile and produce no fruit. Thus, propagating by seed is not an option.

Potting and Repotting

Most ornamental cherry trees are too large for container growing, but it's possible to grow Japanese flowering cherry trees in containers or even as bonsai plants if you choose a compact cultivar. Potted cultivars of P. serrulata require regular pruning. Such plants can make excellent patio specimens.

Use ordinary commercial potting soil in a large, deep, well-draining container (terra-cotta pots are best to aid in drainage). Repotting will be difficult, so start with the largest container possible.

Some experts recommend replacing a good portion of the potting soil every two to three years. Feed the plant with a good controlled-release fertilizer each spring. A potted tree will need to be watered regularly—several times a week in hot weather.

Overwintering

Over much of their hardiness range, Japanese flowering cherries require no winter protection. However, gardeners in the northern part of the range (zone 5) may want to mulch the ground around young trees with a thick layer of dry straw or leaves to protect the roots from cold over the winter months. Clean up fallen leaves and other debris to prevent fungal diseases and insect larvae from overwintering to reappear in the spring.

Common Pests and Plant Diseases

Gardeners who want to enjoy the beauty of a Japanese flowering cherry should be prepared to spend considerable time treating pests and diseases in most years, but the spring bloom is worth it for many. In fact, their susceptibility to a number of pests makes most specimens short-lived. Careful care can keep the plant healthy enough to resist many problems, but don't be surprised if your tree succumbs after 15 to 20 years.

Peachtree borers are a notable pest problem for cherry trees. For borer control, most experts simply advise keeping the tree vigorous (and therefore less susceptible to borer attack) by providing adequateirrigationand fertilizer. You can use spray pesticides formulated for peachtree borer to treat current infestations.

Other small pests that trouble this tree are scale insects, spider mites, and aphids. You can generally blast these pests off the leaves with a strong spray from your garden hose. Tent caterpillars will eat the leaves, so remove their silky nests as soon as you spot them and before much damage can be done. Japanese beetles can also feed on the tree's foliage, and severe infestations can be controlled with spray insecticides.

A number of serious diseases can affect Japanese cherry, including leaf spots, dieback, leaf curl, powdery mildew, root rot, and fireblight. Consult your local Extension service for diagnosis and solution recommendations in your area.

How to Get Japanese Flowering Cherry to Bloom

Bloom Months

Japanese flowering cherry trees bloom quite robustly in spring (any time from March to May, depending on the growing zone) if they are healthy. The best blooms are produced by trees growing in a favorable location with plenty of sunlight and well-draining soil.

How Long Do Japanese Flowering Cherry Trees Bloom?

Japanese flowering cherry trees typically bloom for about two weeks at a time in the spring.

What Do Japanese Flowering Cherry Flowers Look and Smell Like?

The blooms of Japanese flowering cherry trees are about 2 inches across and pinkish-red, with the most dominant color being pink. The flowers grow in clusters all throughout the tree, making for a spectacular display. While they do not have a strong scent, gardeners may catch the subtly sweet and floral fragrance of these flowers up close.

How to Encourage More Blooms

The best way to encourage healthy blooms on your Japanese flowering cherry is to provide the plant with adequate sunlight, moist soil, and checking for pests regularly. Japanese flowering cherry trees can experience a few different issues that impede blooming.

If your tree's flowers are wilting and falling off before opening, it may have brown rot, a fungus that causes brownish spores to appear on the buds and blossoms. Affected leaves and blossoms should be raked up and destroyed. Fungicides may offer some help for brown rot, but you may lose your tree's blossoms until next year.

A tree that gets nipped by hard frost just as the buds are appearing may lose its blossoms for that year. This isn't a serious problem, as the tree will probably bloom just fine the next year. Branches that die back should be removed.

Caring for Japanese Flowering Cherry After It Blooms

After your tree blooms, it's important to remove any dead or overly heavy branches. Pruning these trees before they flower can lead to flowering problems or diseases, so post-blooming is the best time to care for the tree's branches.

Common Problems With Japanese Flowering Cherry

Japanese flowering cherry trees are prone to a number of growing issues. Keeping your tree healthy is the best preventive measure, but the Japanese flowering cherry is a tree that sometimes requires a professional arborist to diagnose and treat problems.

Bark Splitting

A significant problem is bark-splitting, whereby large cracks emerge in the trunk. Such a crack can allow organisms to enter and subsequently cause decay. As a solution, trace with a knife just outside the split in the trunk and then remove the bark from inside the traced area. This will prevent the crack from expanding. If the tree is otherwise healthy, the area should callus over to prevent disease.

Gummy Residue Around Trunk

This is often an indication that the tree is fighting peach tree borers. You may also see wounds and cankers on the trunk of the tree when borers are attacking. Permethrin or other powerful insecticides will likely be necessary to control these pests, but take care not to spray during the bloom period, as this will kill pollinating bees.

Ragged Holes in Leaves

This is usually caused when Japanese beetles are feeding on the foliage. One effective method of control is to use pyrethrin-based insecticides. Horticultural soaps can also be effective, though application on a full-sized tree can be problematic.

From: thespruce