Juniper rocky: planting and care, reproduction and pruning, varieties with photo
Rocky juniper (Juniperus scopulorum) is part of the juniper genus, which belongs to the cypress family. In nature, such a plant can be found in Canada (in the southwestern province of Alberta and British Columbia), in the USA (in the west of Texas, in Oregon and in northern Arizona), as well as in northern Mexico. It prefers to grow on the rocky soil of mountains at an altitude of 1200-2700 meters above sea level. Cultivate this type of juniper is relatively rare.
Features juniper rocky
Rocky juniper is represented by shrubs and dioecious trees. Under natural conditions, such a plant can have a height of 10-18 meters, and the circumference of its trunk varies from 0.8 to 2 meters. However, the juniper growing in the garden is not so tall and thick. In this plant, the crown begins almost from the base, its shape is irregular conical, and over the years it rounds. The color of the bark is brown. Young stems are painted in a pale blue or greenish-blue color. Opposite leaf-shaped ovoid-rhombic leaf plates are usually scaly, their length is 0.2 centimeters, and their width is 0.1 centimeters. The color of the leaves is dark green, green-gray or gray-blue. This plant has needle-shaped needles, its length is 1.2 centimeters, and its width is 0.2 centimeters. Cones of spherical shape are painted in dark blue with a bluish bloom, their length is 0.4-0.6 centimeters. Only at the end of the second year will they fully mature. Inside the cones there are brown-red ribbed seeds, whose diameter is about 0.5 centimeters.
Juniper rocky Blue Herro (arrow) / Juniper planting and care / coniferous plants
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Planting juniper rocky
If you purchased a rock juniper seedling with a closed root system, then it can be planted at any time of the year except winter. In the event that the seedling has an open root system, then it is recommended to plant it in open ground at the very beginning of the spring period after the soil has been well warmed up, but the sap flow should not start yet.
In that case, if you strictly follow the agrotechnical conditions of this type of juniper, then it will be quite simple to take care of it. When choosing a site for planting, it should be borne in mind that it should be open and well lit, and groundwater should lie deep enough. If the variety is dwarf, then for it you should choose a site with poor soil, otherwise such a juniper will not be stunted. High varieties of juniper are recommended to be grown in nutritious soil. Also note that this plant needs a lot of space.
The size of the planting pit should be at least 2 times the volume of the seedling root system. If the seedling is a dwarf variety, then between the bushes a distance of 50 centimeters should be observed. When planting tall plants, leave at least 200 centimeters of empty space between copies, the fact is that after 10 years, such juniper begins to grow actively. At the bottom of the pit, it is necessary to make a drainage layer, the thickness of which should be 20 centimeters, for this you can use crushed stone or broken brick. It is recommended to immerse the seedling with the container several hours before planting in a container with water. In this case, you can carefully extract the plant from the container without damaging its root system. In the event that you can plant a seedling with a clod of earth, it will be much easier for the juniper to take root.
The seedling should be lowered into a pit, which is covered with a pre-prepared earth mixture consisting of peat, turf land and sand (2: 1: 1). The planted plant needs abundant watering.After the liquid is completely absorbed into the soil, the surface of the trunk circle will need to be covered with an eight-centimeter layer of mulch (wood chips, peat, sawdust or pine bark). In a planted seedling, the root neck should be at the level of the surface of the site.
Rocky Juniper Care
Rocky juniper is quite easy to care for, as it is distinguished by its unpretentiousness and resistance to urban conditions. But it should be noted that in the first years after planting, the plant will grow extremely slowly.
Adult bushes need to be watered only during prolonged droughts. However, for the season, juniper can be watered no more than three times. Newly planted seedlings need to be watered more often. Also, seedlings are recommended to be sprayed with lukewarm water, and this should be done in the evening.
It is impossible to feed this plant with organic matter. For young bushes, just one feeding, which is arranged in April or May, is enough, for this they use Kemira universal (for 1 bucket of water 20 grams) or Nitroammofosku (for 1 square meter from 30 to 40 grams). Adult bushes do not need to be fed.
Care for the rocky juniper in the winter is directly dependent on the variety. If the bush has a columnar crown, then after heavy snowfall it is imperative to remove snow from it by shaking it off, otherwise the branches may not be able to withstand such a severity and break. In order to prevent injury to the branches, they must be pulled together with twine before heavy snowfall so that they are pressed against the trunk.
If transplanted juniper, not following the rules, then this can destroy him. The cause of plant death in this case lies in severe damage to the root system. The hardest transplant adult large bushes. What are the rules that allow you to transplant a plant without severe damage? The most important rule is to maintain the integrity of the earth coma when digging a bush, because it is in it that the plant root system is located.
It is recommended to engage in transplantation in March – April or June – July, because it is at this time that the plant has maximum root-forming abilities. But still in the summer it is better to refrain from transplanting, since in the heat of the needles a large amount of liquid evaporates, which leads to a significant weakening of the juniper, as well as to a slowdown in its adaptation. In this regard, transplanting is best done in the spring, but if time is running out, then you can move the bush to a new place in the fall during fall.
Dig a pit to start with, do not forget to take into account the size of the earthen coma of the bush. Then at its bottom it is necessary to make a good drainage layer. Prepare the required amount of soil mixture with which you will fill the pit. When everything is ready, you can begin to extract the bush from the ground. To do this, you need to dig it, not forgetting to retreat from the trunk at least 50 centimeters. The juniper extracted with a lump of earth must be laid on a strong cloth or film, then it is carefully moved to a new landing site. You need to plant a dug bush in the same way as a seedling during an initial planting. The surface of the trunk circle must be covered with a layer of mulch, and do not forget that the transplanted plant needs protection from direct sunlight.
Juniper planting and care
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Diseases and pests
Very often, such a plant becomes infected with rust, which is a fungal disease. In an infected specimen, growths of saturated orange color appear on the branches, they contain oil with pigment, which is very similar in composition to carotene. The infected bush loses its spectacular appearance, its branches begin to dry. A few years later, such a bush dies.If you notice the first signs of rust, then cut off and destroy all the affected parts of the plant in the very near future, and then treat the juniper with a fungicide. Experts advise in this case to use such effective drugs as Bayleton, Skor, Rogor, Vectra and Tilt.
Also quite often, the juniper bush is affected by Fusarium wilting (tracheomycosis). Its development is often associated with the fact that the plant is grown on excessively dense soil with high humidity. This disease affects the root system of the plant, which stops transmitting nutrients to the aerial parts of the plant. The fact is that germination of the mycelium of the fungus into the vascular system of juniper occurs. At the affected bush, apical shoots are the first to dry, their needles change their color to pale red. After some time, the disease affects the entire bush. It is almost impossible to detect the development of Fusarium wilt at an early stage, however, if you notice that the apical shoots of the bush have turned yellow or red, then immediately cut off the infected branches and treat the plant and the soil surface under it with fungicide. For greater effect, experienced gardeners recommend changing the topsoil to a fresh soil mixture, which must be soaked with a fungicide solution. In order to prevent, the purchased material for planting must be subjected to treatment with Quadris, Fitosporin-M or Maxim, without forgetting about the earthen coma. If the seedling is not very large, then its root system must be immersed in Maxim's solution for 2 or 3 hours.
Juniper can also lose its spectacular appearance or even die from a disease called branch drying. You can understand that the bush can be infected in the spring, its needles turn yellow and begin to die, at first it affects not very large areas, but over time, the disease spreads to the whole juniper or to most of it. As the disease develops, small fruiting bodies of mushrooms form on the surface of the bark and needles. A diseased bush should be treated immediately, as the first signs of drying out of the branches were noticed. To do this, cut off all the branches with yellow needles, and the plant itself needs to be treated with a fungicide solution. In the event that the juniper is very affected by the disease, then it will have to be excavated and destroyed. For prevention purposes, it is necessary to spray the bush 2 times per season, namely: in the second half of April and in the last days of October, Tilt, Ridomil Gold MC or Skor are used for this.
Rocky juniper is also able to become infected with brown shute (the name is derived from the German word, which translates as “crumble”). In the affected specimen, the needles turn yellow and fall off. Most often, the disease makes itself felt in the first summer weeks. If you look at the needles infected in the last days of August, then on its surface you can see the fruiting bodies of ellipsoidal and black mushrooms. If the juniper is improperly looked after or grown in the shade, as well as in a damp place, in these cases, this disease will develop rapidly. Branches with yellowed needles need to be cut, and also remove all dead needles that have fallen on the site, then process a copy of Strobi, Skor, Quadrice or Ridomil Gold MC. For prevention purposes, treat the bushes with these drugs should be in mid-April and in the autumn before freezing begins.
Pests such as mining moths, scale insects, aphids, and spider mites can harm this plant. To get rid of aphids, the bush must be sprayed with a solution of Fitoverm, which is prepared according to the instructions.If a mole has settled on the plant, then it must be treated with Decis solution (2.5 grams per 1 bucket of water), and the scabbard can be eliminated with the help of Karbofos solution (70 grams of substance per 1 bucket of water), which also needs to be treated with the bush itself, and soil surface under it. Spider mites are afraid of acaricides, for example: Karbofos, Actellik, Actara and others with a similar effect.
Pruning juniper rocky
Rock juniper is not needed for shaping pruning, because its crown has a very spectacular shape by nature. However, he needs sanitary pruning. How to prune a bush? Pruning is carried out in early spring before the sap flow begins, and a rainy day is chosen for this. Remove all dried, injured, damaged by disease or pests stems and branches, as well as those that grow incorrectly. If you want to align the contours of the crown, then remember that you can shorten the branches and stems by no more than 20 mm, since for a year the growth of this plant is only 10 centimeters.
Grooming and shaping ROCKY SKYROCKET Juniper / Topiary / Thuja Lord /
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Reproduction of Rocky Juniper
Rocky juniper can be propagated by young layering, grafting or grafting. Cuttings are harvested in the spring, for this, the semi-lignified upper shoots with a heel are cut (this is a small piece of wood of the branch from which the shoot grows). Rooted cuttings in a greenhouse. After they take root, they should be landed on a training bed. Depending on the plant variety and the age of the cuttings, it can take 1.5-6 months to take root. It is necessary to grow it in school for 3-6 years.
For propagation by layering, only creeping forms are suitable. The stem must be cleaned from needles and fixed on the surface of the soil of the trunk circle, which must be prepared in advance. After 6-12 months, they are completely rooted. Rooted layering should be cut off from the mother bush and planted on a training bed, located in a shaded place, for growing.
Vaccination to propagate this type of juniper is quite difficult, as it will require certain professional skills.
Rock juniper varieties with photos and names
Thanks to the work of breeders from America, a large number of varieties of rock juniper were born, while all of them are quite popular among gardeners. Varieties that are suitable for growing in mid-latitudes will be described below:
- Blue arrow. The height of the bush varies from 150 to 250 centimeters, the crown is columnar narrow, its width is about 0.5 meters. The needle-shaped scaly green-blue needles have a steel tint.
- Blue Haven. The height of the bush is about 200 centimeters. Its crown of pyramidal shape in width reaches 100 centimeters. The color of the needles throughout the year is light blue with a steel tint.
- Skyrocket. This winter-resistant variety is quite popular among gardeners. When the plant is 10 years old, then its height will reach 3-6 meters. The columnar habit is narrow and slender. Straight stems adjoin the trunk. Greenish-gray needles, usually scaly. This variety is susceptible to fungal diseases.
- Moffat Blue. This winter-resistant variety has a dense crown with a wide pyramidal shape. The color of the needles is greenish-blue. The height of the plant is 3–6 meters, and the width of its crown reaches 100–130 centimeters. This variety cannot be grown in regions with a humid climate.
- Munglow. This variety has many similarities to Blue Haven. The crown of the plant is widely pyramidal. At the age of ten, its height is 250 centimeters, while the crown in width reaches 100 centimeters. The needles have a rich blue-silver color, which in winter looks even brighter.
- Silver king. The bush has open branches. When he turns 10 years old, he reaches a height of only 0.6 meters with a crown width of 2 meters.Needles of blue color, as a rule, are scaly.
- Springbank. This variety is photophilous. The crown is narrow, columnar. The height of the bush does not exceed 4 meters. The ends of the stems are "disheveled", shaggy. Thin needles are painted in blue-silver color.
- Table Top Blue. The shape of the crown is oval. The color of the needles is blue-silver. A ten-year-old plant reaches a height of 200 centimeters, while the diameter of the crown is 250 centimeters.
- Welch. A dense crown has a pyramidal shape. The needles are greenish-blue with a silver tint.
- Wichita Blue. At the bush, the branches are open, and the color of the needles is bluish-silver. At the age of ten, its height does not exceed 0.4 m, while the crown width reaches 1.5 m.
In addition to the varieties described above, gardeners cultivate the following varieties of rock juniper: Winter Blue, Tollesons Blue Whiping, Tollonsons Green Whiping, Sutherland, Monvade, Medora, Greensphere, Erect Glauka, Gray Glim, Colorado Green and others.
Juniper rocky in landscape design
In landscape design, specialists widely use rocky juniper. So, it is used for group and single plantings in rocky and heather gardens, such a plant is framed by alleys, it is decorated with small garden gardens, and it is also used as a vertical accent in various flower arrangements.
The crown of juniper rocky is quite spectacular due to the fact that it is geometrically regular and clear. It is often used as a background for other plants or as a central link in a garden composition. This plant is perfect for those sites that are decorated in English or Scandinavian style, and juniper will look great in alpine or Japanese gardens.