In the landscaping of settlements, not only flowering plants are used, but also decorative leafy ones, for example, kohia, or summer cypress. Today it is a very popular culture in landscape design, named after the German professor of botany Wilhelm Daniel Josef Koch (1771–1849), director of the botanical garden in Erlangen.
In our country - in the steppes, semi-deserts, often on saline soils - about 10 species of kochia grow. In the southern regions, creeping kokhia, or prutnyak, izen is widespread (Kochia prostrata), - a semi-shrub with ascending branches, growing on rocky slopes and salt licks. It is a forage plant that is also used as fuel and is used in breeding.
Cochia broom (Kochia scoparia) Is a strongly branching annual with narrow, sessile, tender, emerald green leaves, which turn reddish by autumn. Thanks to its powerful root system, the plant can withstand significant wind gusts. In the middle and southern zone of the Russian Federation, it grows on any cultivated soils (gardens, vegetable gardens), it is found in landfills, etc. It is bred for the manufacture of brooms.
This species has two garden forms - hairy cochia (Kochia scoparia var. trichophylla) with bright green, emerald leaves that turn purple in autumn, and Cochia Childs (Kochia scoparia var. childsii), which remains green throughout the growing season.
Kokhia broom tolerates a haircut, is perfect for creating various shapes, its bushes in the form of balls, ovals, candles look very original among low-growing summer houses, as well as on a lawn, a flower bed or in the form of green sculptures, accents in flower beds, etc.
In our work, we used broom cochia and its garden forms - k. Hairy and k. Childs.
Cultivation of broom cochia
Cochia is propagated by seeds resembling small (about 1.5 mm; 1 g - 1200 pcs.) Stars. We have been doing research for three years. We used seeds (C1) collected in the fall from seedlings planted in spring, and seeds (C2) obtained a year later from self-sown plants, as well as purchased in a specialized store. In all variants, the seeds were stratified before sowing: they were placed in a moist substrate and kept for some time in a dark, cool place.
In each variant, in mid-April, half of the seeds were sown for seedlings in containers, which were placed on special shelves with fluorescent lamps (LF36W / 33-640 / G13), covered with plastic wrap, and the temperature was maintained at + 18 ° C. Light is needed for the germination of the kochia, so the seeds were only slightly pressed into the prepared substrate and moistened.
The rest of the seeds were sown in early May, without seeding, in open ground in pre-treated light, well-structured soil. The crops were covered with a thin non-woven material of grade 30.
In containers, the germination rate of C1 seeds was 100%, C2 - about 70%, and the seedlings were much weaker, and among them mortality was observed (40%).
The purchased seeds began to germinate only on the 10th day after sowing, the germination rate was 50%. The seedlings were weak, despite the nitrogen-phosphorus-potassium fertilization. On the 2nd day after the emergence of seedlings, the film was removed, which led to the death of many seedlings. Indeed, despite the drought resistance of kochia, seedlings need high air humidity, in addition, the plants must be acclimated before planting in open ground. Therefore, we first opened the remaining seedlings slightly for several hours, increasing the airing time each time, and after about 3 days the film was removed completely. In the phase of 2–3 true leaves, some of the seedlings were cut by 3–5 pcs. in pots with a diameter of 11–15 cm, and in mid-May, when the threat of late spring frosts had passed, they were planted in open ground at a distance of 50–60 cm from each other.
To create a hedge, the kohija was placed in a checkerboard pattern (distance between plants 15–20 cm) and in rows (10–15 cm). In both cases, the fence turned out to be quite dense and uniform.
After transplanting seedlings into open ground, weeding, loosening and watering were regularly carried out. For feeding, a solution of ammonium nitrate (5 g per 10 l of water), potassium chloride (2.5 g per 10 l), superphosphate (5 g per 10 l) was used.
When sowing in open ground, a similar situation was observed: the germination rate of C1 seeds was 100%, C2 - 40%. The purchased seeds germinated only on the 15th day, their shoots and most of the seedlings obtained from C2 seeds turned out to be weak, an additional mortality was observed, which in total amounted to 75%.
The results of the work carried out showed that it is better to use C1 seeds, that is, those collected in the fall from seedlings planted in the spring. To obtain a sufficient number of such seeds, only one bush is needed. The rest of the plants must be cut to avoid self-seeding, which is difficult to control, since small seeds are easily spread by the wind.
Leaving and receiving seeds
Despite the drought resistance of the broom kochia, regular watering is necessary for its better growth and development. In addition, you must remember about feeding. So, in seedlings transferred to open ground, the leaves turned red prematurely. This indicates a lack of phosphorus against a background of low temperatures, that is, either the plants were planted in open ground too early, or they underwent insufficient acclimatization. In this case, additional feeding with superphosphate was required (15 g per 10 l of water).
In the first half of August, the broom kochia began to release flower arrows, then small red flowers opened up. After a while, seeds were formed, which we collected in the following way: we cut off the upper part of the plant, dried it, and soon the seeds themselves fell on the paper.
Studies have shown that broom cochia and its garden forms (to. hairy and K. Childs) is best grown from C1 seeds. In this case, the plants develop well both when sown in open ground and when grown through seedlings. When using store-bought seeds, check the date of harvest and packaging. Before planting, the seeds must be stratified. Sometimes seedlings appeared already on the third day. Seeds purchased or obtained from self-seeding (they can be used only in extreme cases) must be grown only through seedlings. These acclimatized seedlings are larger and grow better after transplanting into open ground.
10 days after transferring the seedlings to a permanent place or 2 weeks after the emergence of seedlings when sowing in open ground, top dressing can be carried out, which is repeated a month later (using a complete complex mineral fertilizer).
Application in landscape design
We used cochia hairy in single plantings and as a hedge (its height reached 50 cm), after thinning, the distance between plants in a row was left 20 cm. The hedge turned out to be quite thick and dense. To give it a rectangular shape, a haircut was carried out (to create a layout, a thick wire was pulled). Such a hedge, even in winter, when the plants are withered, keeps its shape very well and looks attractive in the snow. In spring, old plants are removed and new ones are planted (it is necessary to grow several more specimens so that, if necessary, the composition can be repaired) .
Cochia grows well, giving side shoots, therefore it perfectly tolerates a haircut, after which it is necessary to feed the plants with ammonium nitrate (15 g per 10 l of water). In small groups (2–3 specimens, placed at a distance of 20 cm from each other), hairy hair in the form of fluffy emerald balls also looks great.
The fence, which used the staggered Childs Cochia, was also quite dense.After thinning, the distance between the plants should be at least 30 cm. In this case, trimming was not carried out, and by the end of the season the kochii reached a height of 1.70 m. However, this species is more interesting in single plantings. K. Childs is less demanding on growing conditions.
In addition, we used broom cochia in flower arrangements, rockeries, on alpine slides, in single plantings on lawns and flower beds, as accents. To assess the possibilities of kochia in urban conditions, they planted it near the road (as a tapeworm or in the form of a dense, sheared fence), where the plants developed normally even in areas heavily contaminated with reagents that were sprinkled on highways in winter. In summer and autumn, kohija well protects the areas adjacent to the road from dust, and during rain - from dirt, creates a more aesthetic appearance.
Kochia is light-requiring, but easily tolerates partial shade.
It improves the state of the environment by reducing dustiness, reducing noise levels, etc. This makes it possible to use it as a hedge along roads that run next to parks, squares, boulevards and alleys. It should be noted that the water consumption for irrigation is small.
Thus, kohija and its garden forms can be widely used in landscaping and improvement of urban areas, objects of garden and park and landscape construction. The plant is resistant to unfavorable factors of an urbanized environment, unpretentious and decorative.
In landscape design in the central part and in the south of Russia, as well as in the Volga region, venichnaya occupies one of the leading places among the annuals (10% of the total number of flower crops used).
Summer cypress is an unpretentious, easy to care for, with an interesting color, fast-growing, easy-to-cut plant that grows for a long time, takes root well, therefore it can be an excellent addition to stingy flower beds in decorative design.
1. Tyshkevich N. A. Topiary - model haircut / N. A. Tyshkevich. - M: Weekly Mig, 2009.