Content
- 1 Description of the Japanese Kerry bush
- 2 Winter hardiness of kerria
- 3 Kerria in landscape design
- 4 How kerria blooms
- 5 Features of growing Japanese kerria in the Moscow region
- 6 Kerry varieties
- 7 Planting and caring for kerria in open ground
- 8 How to propagate Japanese kerria
- 9 Diseases and pests
- 10 Conclusion
- 11 Kerry reviews
Kerria japonica is an ornamental medium-sized deciduous shrub belonging to the Rosaceae family. The plant's homeland is the southwestern territories of China and the mountainous regions of Japan. Named after William Kerry, a gardener at the Royal Botanic Gardens, Kew, who lived in the 19th century. The shrub has become widespread due to its unpretentiousness, as well as its spectacular and long-lasting flowering - it produces a large number of bright, lush flowers that resemble small roses, and blooms for about 2 months.
Description of the Japanese Kerry bush
Kerria japonica is an openwork shrub whose height reaches an average of 1-2.5 m, some varieties can grow up to 3 m.The leading quality of the plant is its rapid growth, which allows you to experiment with the form of pruning.
The crown of Japanese kerria has the shape of a cone. The shoots of the bush are erect, twig-like. Their surface is painted in light green tones.
The leaf blade is in many ways reminiscent of a raspberry leaf. The length can reach 8-10 cm, lanceolate in shape, jagged along the edges and tapering towards the end. The upper side of the leaf plate is smooth to the touch; there are small fibers on the bottom. The petiole is bare, 5-15 mm long. In summer, the foliage of kerria is light, pale green, and in autumn the bush transforms - the leaves acquire a rich yellow tint.
Flowers can be either double or simple - it depends on the specific variety. The average diameter of flowers is 4-5 cm.
Winter hardiness of kerria
The winter hardiness of Japanese kerria is average. In the south of the country, where the climate is mild, the bush can be left without shelter for the winter. In conditions of middle latitudes and in the north of Russia, the plant is insulated. It is very important to cover the kerria where the winters have little snow.
The coloring features of the shrub give it a decorative appearance even in the winter months - green shoots, giving off a yellowish tint, contrast perfectly with the white snow.
Kerria in landscape design
The shrub looks equally advantageous both in single plantings and in group compositions, fitting perfectly into the overall picture of a mixed flower garden. The bright flowers of Japanese kerria allow it to be harmoniously combined with dark, monochromatic conifers: thuja, juniper, spruce. Japanese kerria looks no less impressive when used in borders and hedges.
The best neighbors for Japanese kerria include garden crops:
- rose;
- host;
- spirea (varieties that bloom in the summer months);
- azalea;
- Mahonia;
- witch hazel;
- rhododendron;
- hazel;
- vesicular carp;
- derain;
- bloodroot;
- forsythia.
Separately, it is worth noting that Japanese kerria looks good next to ground cover plants: periwinkle, tenacious, phlox.
How kerria blooms
The shrub blooms in late May-early June; there are also late-flowering varieties. The positive qualities of the plant include lush flowering extended over time - it lasts for 3-4 weeks. Depending on the weather conditions in the region, the duration of flowering time of the bush may decrease or, conversely, increase slightly.
Sometimes, in especially favorable years, the bushes can bloom again. Although the second flowering will not be as abundant, it will still add decorative value to the garden.
The fruits of Kerria japonica are a small, juicy drupe of dark brown color, obovate or hemispherical in shape, wrinkled, 4.8 mm long. If you grow a shrub in the conditions of central Russia, the plant will not form fruits.
Features of growing Japanese kerria in the Moscow region
Caring for Japanese kerria in the Moscow region in spring and summer is not much different from growing shrubs in other regions, but in the fall the plant must be carefully prepared for wintering. Otherwise, the bush will freeze with the onset of frost, especially if the winter promises to be little snow.
You can start insulation in October or November, always on a dry, cloudless day.
In the Moscow region, flowers of Kerria japonica appear in May, even before the leaves appear. Flowering lasts up to 25 days.
Kerry varieties
The genus of this culture is represented by only 1 species - Japanese Kerry itself. The lack of species diversity is made up for by a large number of varieties. Some of them are popular in Russia.
Pleniflora
Kerria japonica Pleniflora (Plena, Pleniflora, Flore Plena) is an upright shrub with a dense crown. This variety of Japanese kerria blooms with small double flowers, as seen in the photo below. They reach 3-4 cm in diameter and resemble pompoms. Located singly or 2-3 in the leaf axils.
Golden Guinea
Kerria japonica Golden Guinea is a plant with an elegant leaf shape and quite large flowers. They reach 6-7 cm in diameter. They are simple in type, not terry.
Variegata (Picta)
Kerria japonica Variegata or Picta is a variety with flowers that have 5 petals. This variety is distinguished by the decorativeness of the leaf plate - it has a gray-green color and a light stripe along the edge. Small cream spots are also visible on the surface of the leaf.
The diameter of Kerria Japanese Variegata reaches 1-1.5 m, the height does not exceed 1 m. Usually the bush grows to 50-60 cm in height.
Kerria variety Variegata grows very quickly.
Albomarginata
Kerria japonica Albomarginata is a variety with simple flowers and small leaves. The leaf blade of this variety has a white edge along the edge. Among other varieties, Albomarginata is distinguished by the asymmetry of its leaves.
Aureovariegata
Kerria japonica Aureovariegata is a terry variety of medium height. With good care, the bush grows up to 2 m. If conditions are favorable, the flowering of the Kerria variety Aureovariegata lasts for 3 months.
Simplex
Kerria japonica Simplex is a variety with simple flowers. The shrub has the shape of a ball and grows in breadth, not upward. Bright yellow, medium-sized flowers are located in the axils of the leaves. During flowering, the bush looks like a golden ball.
Planting and caring for kerria in open ground
When choosing a place to plant Japanese kerria, you should adhere to the following tips:
- The shrub loves light and does not bloom well in the shade. As a last resort, you can plant the crop in partial shade.
- Drafts do not have the best effect on plant development. It is better to plant it next to a fence or some building.
- The best type of soil for Japanese kerria of all varieties is loam. This garden crop does not like dry soils, but wetlands should also be avoided.
The plant is planted in early spring, before buds appear. Autumn planting is also possible - a month before the onset of cold weather.
To prevent kerria shoots from breaking from the wind, you can plant other flowering shrubs nearby:
- Kuril tea;
- vesicular carp;
- spirea.
Coniferous crops will also provide good protection.
Preparation of planting material
Kerria japonica seedlings do not need any special preliminary procedures. If desired, you can place them for a couple of hours in a container with water or a special solution that stimulates root growth. So Japanese kerria will take root better in open ground.
Preparing the landing site
The main condition for lush flowering of kerria is loose loamy or sandy loam soil. If the soil is heavy, it is diluted with fine-grained sand. The meager area is dug up and organic fertilizers are applied.
How to plant Japanese kerria
Planting is carried out according to the following scheme:
- In the selected area, dig a hole about 50-60 cm deep. The diameter of the hole should correspond to its depth.
- A bucket of compost mixed with garden soil in equal proportions, 100 g of wood ash and 50 g of mineral fertilizer are poured into the bottom of the planting hole.
- After this, a kerria seedling is lowered into the hole. The root collar should be at ground level.
- Then the hole is covered with earth and watered abundantly.
- To better retain moisture, the soil under the bush is mulched.
Watering and fertilizing
Kerria japonica is a moisture-loving plant, but it tolerates excess water in the soil extremely poorly. If the water begins to stagnate after heavy rainfall or frequent watering, the roots of the Easter rose will begin to rot. To prevent this from happening, during prolonged rains, watering is reduced or stopped altogether.If heat and drought sets in, water a little more often, especially during the flowering period.
The frequency of watering is adjusted according to the condition of the top layer of soil. The next time the bush is watered is when the soil underneath is completely dry. If after watering or rain a dense crust forms on the ground, the tree trunk circle is loosened by several centimeters.
Feed the kerria with organic fertilizers 2-3 times per season, preferably in late April-early May and June. Plantings respond well to fertilization with rotted compost and horse manure in the spring. In autumn, wood ash and complex fertilizers (for example, “Autumn Kemira”) are added to the soil. For 1 m2 about 200 g of ash.
When flowering ends, you can add mullein infusion diluted in a ratio of 1:10 to the soil.
Kerry pruning
Japanese kerria is pruned for sanitary purposes or to maintain its shape in order to preserve the decorative appearance of the bush. In March or April, you should inspect the bush and remove all damaged shoots: frozen or broken under the weight of snow. To stimulate branching of the bush, you can additionally trim the remaining branches by 1/3.
When the kerria finishes flowering, you can begin pruning the faded branches back to the branches that did not bloom—it is on them that buds will form for re-blooming in the fall.Around this time, pruning is done to rejuvenate the bush - for this, all shoots older than 4 years are removed. If the crown of the kerria has become too dense, it is thinned out. Since this crop grows very quickly, you don’t have to be afraid to cut off too much - the bush will recover in the shortest possible time.
Shelter of Japanese kerria for the winter
You can start covering Japanese kerria for the winter as early as October. The latest date is the second or third ten days of November.
Insulate the plant in dry, cloudless weather.
- Gently bend the shoots to the ground, trying not to break them. Kerria should not be placed on bare ground; dry leaves or grass should be placed under the stems; foam plastic can also be used.
- The laid shoots are firmly fixed so that they do not unbend - for this they use a special frame of stakes. It will also serve as protection from snow, which can crush the bush if precipitation is heavy.
- A layer of dry leaves, spruce branches or wood shavings is placed on top of the frame.
- Additionally, the bush is covered with lutrasil. You can use alternative shelter options, but the material must allow air to flow well so that the plant does not rot.
The shelter is removed in the spring, when constant warmth has established and the threat of return frosts has passed.
How to propagate Japanese kerria
Japanese kerria can be grown in the following ways:
- cuttings;
- layering;
- in divisions;
- shoots.
From this list, it is especially worth noting cuttings and propagation by layering - these are the most popular methods of propagating kerria.
Preparation of cuttings occurs as follows:
- Green cuttings are cut in July, woody ones are cut in August.
- Each cutting must contain at least 2 buds.
- The lower cut must be made obliquely.
- Immediately after cutting, the cuttings are placed in a cold greenhouse, in partial shade or shade.
- Cuttings almost always root successfully, but the process is slow. For the winter, planting material is left untouched.
- In the spring, in May, the cuttings are planted in separate containers. Cuttings are grown at home.
- After another year, the cuttings are planted in open ground.
Reproduction by layering is considered one of the simplest methods of breeding kerria. Happens in the following sequence:
- In the spring, before the sap begins to flow, they carefully examine the bush and select one of the most developed shoots on it.
- The branch is bent to the ground and placed in a furrow about 6-9 cm deep; there is no need to dig it in.
- To prevent the shoot from unbending, it is fixed with staples on the ground.
- After 2 weeks, young stems will begin to sprout from the cuttings. When they reach a height of 10-15 cm, the furrow is sprinkled with earth so as to cover the young shoots by 5 cm.
- By autumn, new shoots form their own root system. At this time they can be cut and replanted.
Diseases and pests
For preventive purposes, garden crops are usually treated with various fungicidal agents against fungus and pesticides that repel insects. In the case of Kerry, this is not necessary.The bushes do not get sick and do not attract pests. Health problems with Japanese kerria are limited to the danger of freezing in winter and the risk of rotting roots if the water in the soil stagnates. Otherwise, the bush has excellent immunity.
Conclusion
Kerria japonica is a garden crop that easily adapts to various growing conditions. The only significant drawback of the shrub is its poor resistance to frost - even adult plants and the most winter-hardy varieties need shelter for the winter. As an exception, we can highlight only those shrubs that are grown in the very south of Russia, where the mild climate allows them to be grown without additional insulation.
You can learn more about how to grow Japanese kerria in your garden from the video below:
