Content
Rhododendron is a very attractive plant. The flower has earned the attention of gardeners for its amazing lush flowering. It can be achieved only with proper planting and proper care of the plant. I would like such beauty to be on the site even in a region with a difficult climate. Many do not dare to grow rhododendron, considering the plant not hardy enough. Therefore, planting and caring for rhododendron in the Leningrad region is an important topic for gardeners in the Northwest region.
Features of growing and caring for rhododendrons in the Leningrad region
Florists are concerned about information that rhododendrons require special care and do not tolerate winter frosts. However, in the Leningrad region there are gardens with massive plantings of these beautiful plants.
The key to the successful cultivation of rhododendrons in the gardens of the Leningrad Region is a competent selection of varieties. The choice should be among the winter-hardy species, and then they need to ensure proper planting and further care. In natural conditions, the culture prefers to grow near forests and swamps. You can equally often find both single plants and large group plantings of rhododendrons.
Now there are many hybrids bred by breeders in order to obtain the desired characteristics. Therefore, it is not at all difficult to choose winter-hardy varieties of rhododendrons.
The best varieties of rhododendrons for the Leningrad region
The flower belongs to the Heather family, which brings together many types of trees, shrubs and houseplants. Gardeners usually grow undersized specimens of rhododendrons, almost creeping along the ground, or huge lush bushes, from 3 to 7 m high. It is divided into three main types - deciduous, evergreen and semi-evergreen.
The best of them in regions with cold climates are hybrids with a high index of winter hardiness. A selection of rhododendron varieties for the Leningrad region with a description and photos that tolerate low temperatures well, to help gardeners.
The first of them are representatives of the Katevba group of hybrids:
- Grandiflorum (Grandiflorum) - a lush rhododendron with bright purple inflorescences. The height of an adult plant at the age of 10 years reaches 1.2-2.8 m. It has spherical inflorescences, slightly flattened, consisting of 12-19 flowers without aroma. The color is lavender with yellow-red markings, the crown diameter is 3.0-3.2 m. A famous variety among gardeners of the Leningrad region due to its high frost resistance. Withstands temperatures up to - 32 ° С. Flowering begins in early June.
- Nova Zembla Is a red-flowered, evergreen variety of rhododendron. Just like the previous species of rhododendron, it begins to bloom from June. The flowers are bright, ruby-red, with black blotches inside the petal. Spherical inflorescences of 13-17 original flowers. The flowers have no smell, the leaves of the shrub are dark green, shiny, in shape resemble an ellipse. When the age of 10 years is reached, the rhododendron has a bush height of 1.6-1.8 m, and a crown width of 1.6 m.The maximum height, which is fixed for the variety, is 2.5 m. Winter hardiness is high, it can withstand temperatures down to -32 ° C.
- Polar Night (Pollarnacht, Polar Night) is characterized by rapid growth and longevity. In one place, the rhododendron bush grows well and blooms for up to 100 years. The plant is powerful, grows up to 2 m tall, the crown has the same size. The decorativeness is very high, the violet color of the flowers gives the plant an unusual nature. In addition to the juicy color, the flowers have spectacular corrugated petals, the color of which changes with the degree of illumination. In the light, they acquire a crimson hue, in the shade they become almost black. In the inflorescence, there are up to 20 pieces, each ball resembles a bouquet. The height of an adult rhododendron is about 1.4 m. It begins to bloom in the Leningrad region at the end of May, withstands temperatures down to -26 ° C.
The following selection of rhododendron varieties for the Leningrad region from the Finnish selection group. They are loved by gardeners for their high winter hardiness, undemanding care and excellent appearance. Withstand a drop in temperature - 30-40 ° C.
- The Hague differs in compactness and density of the bush. The bush is quite branched, forms a spherical crown of the correct shape. Diameter - 1.4 m. The height of an adult rhododendron reaches 1.5 m. Flowering in the Leningrad region begins in mid-June, the bush is covered with dense inflorescences of juicy pink color with wavy edges. On the petals are red-orange dots, one inflorescence consists of 15-18 flowers. High frost resistance.
- Hellikki - a variety for planting in the Leningrad region in shaded areas with acidic soil. Young shoots of the bush are soft, pubescent. Young leaves are also covered with white villi. Rhododendron reaches a height of 1.2 m at the age of 10 years. Dark green foliage with bright pink-purple inflorescences make a spectacular contrast with their combination. The inflorescences of the variety are located at the end of the branches, consist of 8-12 funnel-shaped flowers. Blooms from the end of May for a whole month. Withstands frosts down to - 34 ° С. Does not tolerate waterlogging, but requires mulching of the root zone.
- Helsinki University - a hybrid with a very powerful flowering. The height of the bush is 1.5-2.0 m, the diameter of the crown is 1.4-1.6 m. The inflorescences are conical in shape, consist of 12-18 flowers. They are located at the end of the shoot. The flowers are pink with red blotches on the petals. A feature of the variety is considered to be very lush flowering even after harsh winters. Blooms in the Leningrad region from June. The variety is similar to another species - "Haaga", but the color of flowers and stamens at Helsinki University is lighter. It is considered a hardy variety with high frost resistance (up to -40 ° C).
- Elviira for lovers of low rhododendrons. An adult bush has a height of only 0.6 m with a crown width of 0.6-1.0 m. The inflorescences consist of 6-10 cherry-red flowers, resembling bells in shape. Each flower has 6 corrugated petals. In the Leningrad region, it blooms from mid-May to mid-June. The rhododendron variety is considered vulnerable in the spring, loves good snow cover. Requires care when choosing a landing site.
Planting and caring for rhododendron in the Leningrad region
To grow a gorgeous bush in the Northwest region, certain conditions must be met:
- choose the right place for the rhododendron;
- choose a winter-hardy unpretentious variety;
- comply with the landing dates;
- plant the plant correctly;
- carry out the main points of care.
The degree of flowering, health and appearance of the rhododendron depends on the quality of each stage.
When to plant rhododendron in the Leningrad region
Landing is allowed in spring or autumn. The main thing is that this event does not affect the flowering time and 10-15 days before and after. In order for a plant to develop well, it needs time to get used to a new place and conditions.Spring planting in the Leningrad region avoids the possibility of freezing of a young bush. If you plan to plant a rhododendron in the fall, then in the Leningrad region it is recommended to take plants with a closed root system for these purposes.
Landing site preparation
For a rhododendron, it is important to choose the right place and prepare the soil. Heathers love acidic nutritious soil and partial shade. Stagnation of water is unacceptable. Based on these preferences of the rhododendron, a site with natural penumbra is chosen for planting a plant in the Leningrad Region. This may be the neighborhood with conifers, which will shelter the young rhododendron from the heat and direct sunlight. The north or northeast side of the house will also work well. It is not worth taking the risk, knowing the thermophilicity of heathers, and planting them in bright sunlight. The close location of the reservoir will be ideal.
The second condition for a successful landing in the Leningrad region is the absence of strong winds. If there is no such site, then you will have to cover the bush with a hedge or a decorative screen. Planting rhododendrons completely under trees is not worth it. Light partial shade does not mean permanent shading. It is undesirable for rhododendrons to be close to birch, spruce, linden. But as an addition, pines, oaks and fruit trees are well suited.
The soil in the Leningrad Region also needs to be prepared.
The heavy clay structure is especially unfavorable for rhododendrons. If it is planned to plant several plants, then the place is prepared for all at once, and not for each bush separately.
The plant pit should be 70 cm in diameter and 50 cm deep. The bottom is covered with drainage to drain excess water. Sphagnum is placed on half of the volume, then a quarter is filled with humus mixed with acidic nutrient soil. Fallen leaves or needles, pine cones will be a good addition to the mixture. The soil should be loose.
Rules for planting rhododendrons in the Leningrad region
After preparing the pit and laying the soil mixture, the soil must be well watered. If the plant is bought in a planting pot, then it is simply transferred with a lump of earth into the hole. The free space is filled with the remaining soil and watered again. From above, the peri-stem zone must be mulched with a layer of 5 cm.
In order to properly plant a rhododendron in the Leningrad region with an open root system, you will need to remove a layer of soil 1 m thick in the area allocated for planting. Shield the resulting pit from the sides with natural materials. This must be done so that moisture and nutrients remain in the planting area when feeding the bushes. Lay a drainage layer 20-30 cm thick at the bottom. Large crushed stone or broken brick will do. Pour sand on top (10-15 cm).
Prepare a solution of the drug "Extrasol" (10%) and immerse the roots in it for 10-15 minutes.
Carefully place the seedling in the hole, cover with soil. In this case, care must be taken not to deepen the root collar.
In the Leningrad Region, a transplant option is possible for rhododendrons if young plants are not planted in a permanent place. The bushes are transplanted in the spring. The second term is the end of summer in August or the beginning of autumn - September. When transplanting a rhododendron, it is important to maintain the depth that was at the first planting. Then the plant is surrounded by a layer of moss and needles 10 cm thick.
Watering and feeding
There are the main nuances of care in the Leningrad region, without the high-quality implementation of which it will not work to grow a luxurious rhododendron bush. When watering, it is necessary to maintain the golden mean. The plant loves moisture, but does not tolerate stagnation.Therefore, it is necessary to monitor the absorption of moisture and maintain the looseness of the soil. If there is stagnation, then quality drainage is needed. To balance the moisture intake, gardeners:
- Rhododendrons are planted in the Leningrad region on high ridges. They are raised 10-15 cm above the average level of the spring flood.
- Be sure to add loam to the soil mixture. It prevents peat and pine litter from churning into a lump, which significantly reduces the quality of irrigation.
- Use melt or rainwater. Plants react worst of all to tap water because of the admixture of chlorine.
- The leaves are periodically irrigated by sprinkling. This is especially true during the dry, hot months of summer.
Another important event for gardeners in the Leningrad Region is top dressing. The most suitable feeding periods for rhododendron begin in the spring at the time of flowering and in the fall, 2 months before the first frost.
It is important to remember that conventional nitrogen fertilizers are ineffective for this type of plant. Gardeners of the Leningrad Region need to use special formulations for acidic soils. Fertilizers are applied for the first time at the beginning of the flowering of the bush. If you do this earlier, then the nitrogen components will negatively affect the development of flower buds. They just start to crumble. The main nuances and nutritional schedule for rhododendrons in the Leningrad region:
- Nitrogen fertilization at the end of March. For one bush, 15-20 g of ammonium sulfate is enough. An alternative would be an infusion of cow dung.
- Phosphorus and potash components are introduced in mid-June. The end of summer is not the best period. If you feed the rhododendrons at this time, they will grow.
In addition, the bushes must be mulched with pine or spruce bark with a layer of 3 cm. However, loosening for rhododendrons is contraindicated due to the close location of the roots to the soil surface.
Do not use ash, clay or lime while caring for plants. These substances change the acidity of the soil, which will not affect the life of the bushes in the best way. The optimal acidity index for rhododendrons is 4.5-5.0 pH.
Pruning
In addition to watering and feeding, it is very important to prune the rhododendron.
Pruning involves achieving several goals:
- Removing wilted inflorescences. They continue to be cut until the seed is formed. Thus, the grower helps the plant conserve vital resources and stimulates the establishment of new flower buds for the next season.
- Crown formation. Spring pruning in early March involves cutting off young shoots above dormant buds. At the same time, a rhododendron crown is formed in the form of a ball.
- Bush renewal or crown reduction. In this case, the shoots are cut under the fork. The thickness of the branches to be removed is no more than 2-4 cm.
Protection against diseases and pests
In the Leningrad region, rhododendrons can be affected by fungal diseases. Most often there are leaf spots, rust, cancer. The first two diseases are removed with the help of copper sulfate, which is used to treat plants. If the variety is sick with cancer, then the affected shoots are removed and burned. Preventive treatments for the disease are made with Bordeaux liquid twice a year - in spring and autumn.
An important point that leads to infection is a violation of agrotechnical requirements:
- poor aeration of the soil;
- excessive watering;
- lack of preventive treatments.
Among the pests in the Leningrad region, thrips, scale insects, whiteflies, spider and rhododendron mites, snails, and slugs should be noted. You need to deal with them with insecticidal preparations.
Preparing rhododendrons for winter in the Leningrad region
Frost protection is very important to maintain the vitality of the plant. Shelter methods in the Leningrad region are slightly different for different types of rhododendrons.
- Deciduous. The shoots are bent to the ground, but make sure that the buds do not come into contact with it. Sprinkle the planting sites with dry foliage or peat with a layer of 15 cm. This is necessary to protect the root collar.
- Evergreen varieties require shelter. It protects plants not so much from frost as from drying out. They begin to cover the rhododendrons at the onset of the first frost. Be sure to leave ventilation holes so that the plants do not rot during warming.
The first year, the bushes are covered with non-woven material. Lutrasil, spunbond and frame structures are used. In spring, rhododendron bushes are opened gradually, in several stages. They begin in cloudy weather and continue to adapt plants for 10-15 days so that there is no sunburn.
Reproduction
There are only two main ways of reproduction of rhododendrons for Leningrad gardeners - by seeds and cuttings.
Deciduous varieties prefer to propagate in shifts. They ripen in September. Sowing is started in early spring, after germinating the planting material at a temperature of + 10-15 ° C. This usually takes 8-10 days. The soil for seedlings is prepared from a mixture of sand, peat and coniferous soil. After the appearance of 2-3 leaves, the seedlings are dived, then grown in a greenhouse. Such rhododendrons begin to bloom in 5-10 years.
Lignified apical shoots are suitable for cuttings. Cutting diameter 3-5 cm, length 3-4 internodes. For rooting, mixtures are prepared:
- peat soil + sand (2: 1);
- heather soil + sand (2: 1).
The material is harvested in July, leaves must be left at the top of the cutting. The lower end of the cutting is immersed in a solution of Heteroauxin, then placed in a soil mixture. The lower part of the container in which rooting takes place must be heated with warm air. For this, the containers are lifted off the ground. Rhododendrons take root slowly. A transplant is available only after a year. If the cuttings are immediately placed in the ground, then the first winter they are reliably covered. During the growth period, the cuttings produce 3 pinches.
There is another method of propagation of deciduous rhododendrons, in which they begin to bloom the next year - by layering. You need to dig in last year's shoots and water regularly. Use Heteroauxin solution once a month. The next fall, the cuttings are separated from the mother bush.
Conclusion
Planting and caring for rhododendron in the Leningrad region is available even to novice gardeners. If you follow the agrotechnical requirements and monitor the condition of the bush, then its lush flowering will be a worthy reward for your efforts.
