Cherry trees are normally planted in the fall, well before frost to give them a chance to establish roots. These are fast-growing (1 to 2 feet per year), but rather short-lived trees. The leaves, stems, and seeds of cherry trees are toxic to pets and humans. These are temperamental plants that are susceptible to a large number of pest and disease issues. 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. It’s a rare year where you won’t be treating the tree for some insect or fungal disease, but the spectacular spring bloom is worth it for most gardeners.
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 tolerate partial shade.
Soil
This type of cherry tree will tolerate a variety of soil types, but it prefers moist, fertile, well-drained loam with a relatively neutral pH. 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
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 these trees, 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 with some compost when planting and top-dress periodically thereafter, watering the nutrients into the soil.
Types of Japanese Flowering Cherries
The genetic heritage of the Japanese flowering cherry is a complicated one, as P. serrulata likely is the result of crossbreeding of many wild species, along with the Oshima cherry (Prunus speciosa). Most commercially available Japanese cherries are grafted trees, in which ornamental cultivar branches are fused to a wild cherry rootstock. There are several popular award-winning cultivars of P. serrulata, including:
‘Kanzan’ is a very popular variety that grows up to 30 feet high 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, has arching, cascading branches. It grows to 15 feet tall and wide and has rich pink double blossoms.‘Fugenzo’ has beautiful white flowers that gradually turn pink. It grows to 30 feet tall and wide.‘Shirotae’ has large pure white flowers, up to 2 inches across. Growing to a maximum of 20 feet with slightly arching branches, it is ideal for small landscapes.‘Asano’ has puffy, full flowers resembling those of chrysanthemums. It grows to 20 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. Make sure to sterilize your cutting tools after each cut. Sometimes, the limbs can grow too quickly and heavy for the base. Prune away the heavy branches as needed.
Propagating Japanese Cherry Trees
Most ornamental cherry trees are created by grafting branches from a selected cultivar onto the hardier rootstock of a wild cherry. Therefore, propagating them yourself is an iffy prospect, since 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. But if you wish to experiment with propagating through stem cuttings, here’s how to do it:
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 if you choose a smaller cultivar of P. serrulata and are willing to prune regularly, it is possible. Such plants can make excellent patio specimens. Use ordinary commercial potting soil in a large, deep, well-draining container. 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 of fallen leaves and other debris can prevent fungal diseases and insect larvae from overwintering to reappear in the spring.
Common Pests and Plant Diseases
Unfortunately, these beautiful trees are susceptible to many pests and diseases. In fact, their susceptibility to a number of pests earns them the dreaded “short-lived trees” label. Gardeners who want to enjoy the spectacular beauty of Japanese flowering cherry should be prepared to spend considerable time treating pests and diseases. Peachtree borers are a notable pest problem for these (and other) cherry trees. For borer control, most experts simply advise keeping the tree vigorous (and therefore less susceptible to borer attack) by providing adequate irrigation and 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 before much damage can be done. Japanese beetles can also feed on the tree’s foliage. Control severe infestations of Japanese beetles 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.
How to Get Japanese Cherry to Bloom
Japanese flowering cherry trees will normally bloom quite robustly if they are healthy and in a favorable location (plenty of sunlight, well-draining soil). One problem that can affect a tree’s bloom is brown rot, a fungus that causes brownish spores to appear on the buds and blossoms. The flowers often shrivel and fall off before they can even open. 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 also lose its blossoms for that year. This isn’t a serious problem, as the tree will probably bloom just fine the next year. But branches that die back should be removed.
Common Problems With Japanese Cherry
Japanese flowering cherry trees are prone to quite a number of common symptoms, a few of which are listed here. 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 disease 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 and, if the tree is otherwise healthy, the area should callous over, preventing the incursion of disease organisms.
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. Ake
‘Accolade’ is a cultivar of P. subhirtella, which is itself a complicated hybrid. Growing to 25 feet with an arching habit, this variety has beautiful shell-pink flowers.Yoshino cherry (Prunus x yedoensis) is a slightly larger tree (up to 40 feet) that produces small berries, bitter in taste but popular with birds. It has good fall color and is useful as a small shade tree. Its flowers are white, tinged with pink.‘The Bride’ is a cultivar of Prunus incisa. It has pure white flowers with pink/red centers. Growing to just 6 to 7 feet, it is a good choice for small patio gardens or for growing in containers.
