Content
Douglas spirea is a member of the Rosaceae family, which includes more than a hundred species that differ in growth and color. The habitat of the ornamental shrub is Asia (Himalayas), part of Mexico, found in mountainous areas and forest-steppe. The plant is frost-resistant and tolerates drought well. On the territory of the Russian Federation it is used as an element in the design of a site.
Description of Douglas spirea
Douglas spirea (spiraea Douglasii) is a deciduous plant with a long flowering period. The first flowers appear in July, the peduncle ends in a temperate climate after a month and a half, in the South - until the end of autumn. External features of spirea:
- The shrub is 1.5 m high and produces a significant number of erect shoots. The stem structure is rigid, strong, flexible, light brown in color with a burgundy tint. Branches with dense edges.
- Spiraea has oblong leaves up to 10 cm long. The plate is rich green in color, with a two-tier structure. The lower part is oval in shape, smooth at the edges, framed in the middle by a jagged structure, tapering at the top. The reverse side of the leaf is silvery with a strong edge.
- The root system is fibrous, dense and well-expanded.
- Small multiple flowers of a dark pink hue, collected in panicles (up to 15 cm). A pyramidal inflorescence is formed at the top of the stem. Protruding white stamens add decorativeness; the panicle looks as if in an openwork cocoon.
Douglas bush grows quickly. After 3 years it reaches its maximum height and begins to bloom.
Douglas spirea in landscape design
Spiraea of this type is the most popular among professional designers and amateur gardeners. The Douglas variety is planted in compositions as a background accent, as a decoration for alleys, near bodies of water.
The use of Douglas spirea (pictured) in landscape design of the site:
- in the form of a composition in the center of a flower bed;
- to highlight a certain part of the garden;
- distribution along the edges of the garden path creates a visual perception of the alley;
- as a hedge to designate zones on the site;
- to create a background near the wall of a building.
In combination with low-growing flowers, the plant is used in rockeries to attract attention to a certain composition of stones. Distributed along the edges of the alpine hill.
In city recreation areas, squares, and parks, Douglas spirea is planted as a hedge near sanitary areas, benches, and along alleys. Combines harmoniously with conifers, juniper, Japanese pine. Douglas spirea placed under a maple will highlight the foliage of the tree.
Planting and caring for Douglas spirea
Spiraea Douglasii is a perennial, summer-flowering plant, determined to a permanent place in early spring, when the soil has thawed enough for planting to be carried out, or in the fall, until sap flow has ended and it has shed its leaves.
Preparation of planting material and site
Douglas spirea is a heat-loving plant that can grow in one place for up to 15 years; this factor is taken into account when choosing a site. The bush can be in the shade for a certain time without harming flowering, for example, several hours a day. Constant shading and dampness are unacceptable for the species.
The soil for planting is fertile, loose, and well-drained. The composition of the soil is slightly acidic or neutral. The roots of the plant are fibrous and prone to rotting. If there is groundwater in the area close to the surface, the shrub will die. An unsuitable place for planting is a lowland with insufficient lighting and accumulation of water.
Planting material is selected with a well-developed, healthy root system. Damaged areas or dry fragments are cut out before planting. The seedling is dipped in a manganese solution for 2 hours, then placed in a root growth stimulating agent for a day. Treated with fungicide.
Landing rules
If Douglas spirea is part of the composition, it is planted in the hole. For a hedge, seedlings are placed in a trench, the depth in both cases is 50 cm. The width of the hole is 15 cm larger than the root system, the distance between the bushes is 60 cm. Algorithm of actions:
- A twenty-centimeter layer of drainage (pebbles, gravel) is laid at the bottom.
- A soil mixture consisting of equal parts of fertile layer and compost is poured on top.
- The spirea is placed vertically in the middle, the roots are distributed, and covered with soil.The root collar should be 3 cm above the surface.
- Compact the soil, water it, and mulch it with peat.
Watering and fertilizing
Douglas spirea does not require constant watering, twice a month is enough, but with plenty of water. If the weather is dry, irrigation is increased. The soil should not be allowed to dry out or become waterlogged. Be sure to loosen the soil and remove weeds.
Fertilizing is applied in the spring at the beginning of the growing season, diluted in water with organic matter, and two weeks later with superphosphate agents. The Kemira Universal fertilizer applied at the root has an effective effect on the growth of shrubs.
Pruning Douglas spirea
Douglas spirea blooms in summer, its crown is formed in the spring, before the leaves appear. Remove old branches and young shoots that thicken the crown. Cut out frozen shoots and shorten the tops. The top part of a young plant is cut off to well-developed buds.
After four years of growth, Douglas spirea is subjected to drastic pruning, leaving 25 cm from the root. The shrub will quickly restore new shoots without compromising flowering. It is not advisable to trim the tops; spirea will form thin stems with small inflorescences. Pruning activities continue every year. If Douglas spirea produces weak growth, the plant is transplanted to another area.
Preparing for winter
The frost-resistant crop spiraea Douglasii, grown in the European zone, tolerates low temperatures well if certain preventive measures are taken. The root system of the plant is superficial, so shelter is necessary.The root circle is mulched with dry leaves, peat or pine needles, and the Douglas spirea is first covered with soil to a depth of 30 cm. There is no need to bend and cover the branches; in the spring the bush will quickly recover; it is better to tie the shoots into a bunch.
Reproduction
Douglas spirea is propagated on the site by several methods: seeds, division, cuttings, layering. Planting material is taken from the mother plant (at least 4 years old). Spiraea is rarely propagated by seeds; the process is lengthy, and planting material does not always produce the required number of seedlings. This method is used in the hybridization of new ornamental varieties.
Productive and labor-intensive methods of reproduction:
- By layering. The side branches are bent to the ground, secured and sprinkled with soil. The work is carried out in early spring. Over time, a root system will form from the buds. After two or more young shoots appear, the branch is cut off from the bush, removed from the soil, and divided by the number of seedlings formed. Douglas spirea has a good survival rate; young shoots are immediately planted in a permanent place of growth.
- Dividing the bush. This method is used in the fall, approximately in September, so that there is enough time for the root system to adapt. Spiraea is removed from the ground and divided so that each part consists of several shoots and a strong root lobe.
- Cuttings. At the beginning of September, 15 cm fragments are cut from an annual shoot. Placed in a container with soil at an angle of 400, covered with a film with holes for oxygen access.
In winter, containers with Douglas spirea cuttings are covered with leaves and sprinkled with snow. In the spring, cuttings are opened and planted in early June.
Diseases and pests
Douglas spirea practically does not get sick.The most common pest that parasitizes the plant is the spider mite. The female insect overwinters under fallen leaves from the bush, lays eggs on the leaves in the spring, and produces up to 10 clutches per season. Affected leaves die and fall off. The growing season slows down, and Douglas spirea loses its decorative appearance. For preventive purposes, remove fallen leaves and loosen the soil. In hot weather, completely irrigate the bush. Treated with the following agents: “Acrex”, “Keltan”, “Phosfamide”.
Aphids are less common; they feed on spirea juice, and the colony grows rapidly. Without timely measures taken, the plant will not produce flowers, shed its leaves, and stop growing. The pest is neutralized with drugs: “Pyrimor”, “Aktellik”, “Bitoxibacillin”.
Conclusion
Douglas spirea is a perennial shrub widely used for the design of garden plots and urban recreation areas. The frost-resistant plant is distributed throughout Russia. Undemanding to care, tolerates drought well. The deciduous shrub blooms in cone-shaped, large inflorescences of a dark pink hue.
