Spiraea japonica Crispa

Many lovers of ornamental gardening are familiar with the Japanese Crispa spirea, a low, compact, rounded shrub. This is one of the few plants that combine a lot of positive qualities: excellent appearance, long flowering period, ease and undemanding care. In addition, the shrub has good frost resistance, which allows it to be grown in various regions of the country.

Description Spirea Crispa

Spirea Japanese Crispa (pictured below) is a small shrub with a dense cap-shaped crown. It is an ornamental form of Japanese spirea – a perennial deciduous shrub of the Rosaceae family, growing in China, Korea and Japan.

The main characteristics and description of the Japanese Crispa spirea are presented in the table.

Spiraea Japanese Crispa in landscape design

Due to its compact size, dense rounded crown and long flowering spirea, the Japanese Crispa has found wide application in landscape design. It is planted both in single and in group plantings. Often, a flowering shrub is used as a color accent, the centerpiece of a flower bed, or a single plant when planted in containers or flowerpots.

In group planting, Crispa spirea is effective in mixboards, mixed plantings, as an element in the design of paths and alleys, as one of the steps of a multi-level or low separate hedge.

Planting and caring for Crispa spirea

It is best to plant this ornamental shrub in open ground in spring or autumn, and if the seedling has a closed root system, then in summer. Planting and caring for the Japanese Crispa spirea is simple and will not cause difficulties even for beginners.

Preparation of planting material and site

It is advisable to purchase planting material in specialized stores or nurseries. Sometimes seedlings of this plant can be found there under the name Curly Crispa Spiraea. They are sold, as a rule, in special landing containers filled with earth. Often there are seedlings with roots smeared with clay mortar. If the root system is open, it must be inspected. A spirea seedling suitable for planting should have a significant amount of thin long roots – lobes, as well as healthy, strong taproots with no signs of rot.

Japanese Spiraea Crispa grows well in open, well-lit areas, it is also allowed to plant it in light partial shade. The plant is unpretentious to the composition of the soil; it grows on both slightly acidic and slightly alkaline soils. However, it is desirable that the acidity be close to neutral, so gardeners often make oversized planting pits, filling them after planting with pre-prepared soil with an optimal pH level.

The planting hole is made in advance, usually 1/3 larger than the size of the root system. A drainage layer of fragments of brick or crushed stone is laid out on its bottom.

Planting Spirea Crispa

It is best to plant Japanese spirea Crispa in open ground on a rainy cloudy day. Before planting, the container with the seedling is abundantly spilled with water. This will make it easier to take it out. The plant is planted in a planting hole along with a clod of earth. Open roots must first be straightened. Then the pit is covered with earth in such a way that the root neck of the shrub is flush with the surface of the earth. Then the Crispa spirea seedlings are cut off by about 1/3, after which abundant watering is carried out, and the root zone is mulched with peat.

Watering and top dressing

In most cases, precipitation is enough for the Japanese Crispa spirea to feel good and grow without any problems. In dry periods, you can make an exception and water the root zone at the rate of 1 bucket for each bush.

If the land on the site is fertile enough, there is also no need to feed the spirea. If the soil is poor, you can use mineral fertilizers, which are applied to the trunk circle. In the spring, this is any nitrogen-containing substance, for example, nitrophoska, in the summer, potassium-phosphorus fertilizers for abundant flowering, and in the fall, superphosphate for better preparation for winter. Many flower growers use special complex compositions, such as Kemira-Universal, making them 1 time per season, in early spring.

Trimming

Spirea Crispa tolerates pruning well. In order for the shrub to always have a neat appearance, it is recommended to regularly do sanitary pruning, cutting out dried or damaged shoots. In addition, there are several more types of shrub pruning:

• stimulating;
• formative;
• rejuvenating.

You can start pruning Crispa spirea bushes 3-4 years after planting. Stimulating pruning is carried out to increase the density of the bush and compact its crown. To do this, in early spring, lignified shoots are pruned at a height of 20–25 cm from the ground. Such a bush will begin to bloom in July. If stimulating pruning is not done, the bush will bloom earlier – in June. In this case, it is advisable to remove faded inflorescences without waiting for the seeds to ripen in them. Such a measure contributes to the repeated flowering of the shrub in September, if the weather is warm enough.

The formative pruning of Crispa spirea consists in giving the crown of the shrub a certain geometric shape (most often the correct hemisphere) and further pruning the shoots that go beyond its dimensions.

Sufficiently old Crispa spirea bushes may require anti-aging pruning. With this procedure, the bush is simply cut off at ground level. The buds remaining in the region of the root neck will start to grow in the spring, and thus a new bush will form on the already existing root system.

Preparation for winter

The winter hardiness of Crispus spirea is very high. In the middle lane, the shrub can easily winter without any shelter. Most gardeners do not take any measures to prepare for winter, however, for greater certainty, it is advisable to mulch the root zone with a thick layer of peat, bark or sawdust in the pre-winter period, and then simply throw snow on the bush itself.

Reproduction

Like most shrubs, the Japanese Crispa spirea can be propagated by seed and vegetative methods. Seeds are harvested 1,5-2 months after flowering, so that they are fully ripe. The collected material is stratified, keeping for several months at a negative temperature. To do this, you can use any container that can be stored in the refrigerator or simply buried in the snow. In early spring, seeds are planted under a film, and after 2-3 months, young plants are transplanted into a greenhouse for growing.

However, the seed method does not guarantee that a varietal plant will grow from the seed. When propagated by seeds, only species characteristics are preserved, while varietal characteristics may be lost. Therefore, Crispus spirea is more often propagated by the following vegetative methods:

• grafting;
• division of the bush;
• layering from the mother bush.

Cuttings are an easy way to propagate spirea, while retaining all varietal characteristics. Cuttings are cut in September from the shoots of the current year so that each has 5 leaves. The bottom leaves are removed, the top 2 leaves are cut in half. The finished planting material is placed with the lower cut for 12 hours in Epin’s solution, then treated with Kornevin powder and planted in a container filled with wet sand. The cuttings are deepened by 2 cm at an angle of 45 °. Then the container is covered with glass or film and placed in a warm place.

From time to time, spirea cuttings are ventilated, removing shelter, and also sprayed with water, keeping the sand moist. Rooting usually occurs in 1-2 months, after which young spirea seedlings dive into separate containers.

The division of the bush is a simple, but rather laborious way of propagating the Japanese Crisp spirea. This event is usually held in September. A spirea bush at the age of 3-5 years is completely dug up, the earth is washed out of the roots with a pressure of water from a hose. Then, using a garden pruner, the bush is divided into several parts – the so-called divisions. Each of them should have several well-developed shoots, taproot and fibrous roots.

Ready-made delenki are seated in the planting pits in the same sequence as in the usual planting of seedlings.

Layering can be obtained by bending a long side shoot of the Crispus spirea to the ground and fixing it in this position. The contact point must be sprinkled with earth. If you regularly water this area, the allotted shoot will quickly take root and expel its own sprout. In this position, the plant is left for the winter. In early spring, the cuttings can be separated from the mother shoot, dug up along with the roots and transplanted to a permanent place.

Diseases and pests

Diseases rarely attack Crispus spirea. Most often this happens on old neglected bushes, for which there was no any care. The lack of pruning leads to a strong thickening of the internal space, a violation of air exchange provokes increased humidity. Under such conditions, fungi multiply rapidly, especially if the summer is cool and rainy. When signs of the disease appear, the affected shoots must be cut and burned. You can stop the spread of the fungus by spraying the bush with a solution of any fungicide, for example, copper sulfate.

Of the pests, aphids, leafworms and spider mites most often appear on the Crispus spirea. You can get rid of them by spraying with special means. With early detection, this can sometimes be avoided by simply cutting off the leaves along with the insects.

Conclusion

Spirea Japanese Crispa is a beautiful and unpretentious shrub. You can decorate them not only with a garden, but also with any adjacent territory: a flower bed near the entrance, a flower garden, a path in the garden. Excellent winter hardiness and minimal care requirements make planting this shrub doubly justified. A long flowering period and a beautiful appearance will satisfy even the most demanding grower.