Selecting a variety, planting and caring for rhododendron in the Leningrad region

Shrubs with showy flowers are no longer uncommon in regions with harsh climates. This became possible thanks to the work of breeders who tirelessly develop more and more new varieties of winter-hardy plants. Planting and caring for rhododendrons in the Leningrad region is not difficult. You just need to choose a hardy variety and give the plants some attention during the season.

Description and features

Rhododendrons are one of the brightest representatives of the heather family. They like to grow in humid climates, for example, in the coastal zone of reservoirs, as well as on mountain slopes, as the lower layer of forests. Depending on the species and variety, rhododendrons grow as a deciduous, semi-evergreen, evergreen shrub or tree. Their height ranges from 10 centimeters to 30 meters.

Rhododendrons differ from each other not only in height, but also in the shape of leaves and inflorescences. The color of the buds varies from white and yellow to pink and even purple. Some types of rhododendron have flowers that have a delicate floral scent. At the end of the growing season, fruits are formed, inside of which there are small seeds. The plant attracts bees and is an excellent honey plant.

Additional Information. Rhododendron macrophylla was chosen as the state symbol of Washington.

Frost-resistant varieties

Breeders have developed many varieties that can grow in regions with harsh climates, such as, for example, in the Leningrad region. The most attractive of them are the following.

Helsinki University

The variety is very popular for its soft pink inflorescences with wavy petals. The plant tolerates temperature changes well.

Mikkeli

The leaves of this rhododendron are green, with silvery hair underneath. The flower is initially pink, gradually becoming completely white.

Pekka

The bush grows 3 meters in width and the same in height. The inflorescences consist of large pink petals. The leaf blades are yellow-green.

Peter Tigerstedt

The bush looks impressive due to its large, burgundy-speckled, white flowers. Grows straight, branches weakly.

Haaga

This is a plant with large pink clusters of inflorescences. The bush has erect branches that form a rounded crown. The leaves are dark green.

Hellikki

This variety of short-fruited rhododendron has delicate white or pink inflorescences that bloom in mid-summer. The bush grows up to 2-3 meters, its leathery leaves reach a length of 20 centimeters.

Kullervo

At the budding stage, the flowers are red in color; during the dissolution period they change to white. The crown of the plant is rounded, the leaves at a young age are covered with pile.

Elviira

The variety is slow growing, reaching a height of 50 centimeters. Belongs to the creeping group of rhododendrons. The petals of the plant are dark red.

Pohjola's Daughter

Rhododendron grows up to 1 meter, each purple inflorescence contains up to 10 flowers. The variety can withstand frost down to -34 °C.

Lights Series

Rhododendrons of this series were bred at the arboretum of the University of Minnesota. They are ultra-winter-hardy: they can withstand temperatures down to -40 °C. The most famous varieties: Northen Lights, White Lights, Pink Lights, Rosy Lights.

The value of frost-resistant varieties of rhododendrons is that plants that survive the winter will bloom spectacularly this season, since flower buds are formed at the end of last summer.

Soil selection and preparation

Rhododendrons develop only in acidic soils, so they need to be planted in slightly decomposed high-moor peat. The necessary material is sold in flower shops. If it is not possible to purchase it, you can take litter from under coniferous trees.

But it is not fresh needles that are used, but those that have lain for several years.The best option would be a substrate consisting of turf soil, pine litter and sand.

Rules and terms for planting in open ground

Rhododendron is planted in spring or autumn. If the bush has developed in a container, it can be planted at any time, from April to November. The landing site should be slightly shaded. When placing other plantings next to rhododendron, you need to take into account that it has a superficial root system, and its neighbors may be trees and shrubs with tap roots.

Preparing the landing hole

Having chosen a place for planting rhododendrons, the gardener needs to perform the following steps:

• dig a hole of such depth and width that it exceeds 2 times the volume of the root system of the plant being planted;
• Place material at the bottom of the hole that does not allow moisture to linger at the roots of the bushes (expanded clay, small stones, sand);
• Fill the hole halfway with the prepared substrate.

After this, the bush is pulled out of the pot and, without breaking the earthen ball, planted in the middle of the hole. Then it is covered with earth so that the root collar is above the soil surface.

Advice! It is recommended to dig the planting hole 2 weeks before planting the rhododendron so that the soil has time to settle.

Planting scheme

The volume of the planting hole depends on the size of the seedling's root system. The distance between plantings is selected depending on the bushiness of the variety and ranges from 130 to 180 centimeters. The distance between rhododendrons and tall trees and shrubs is 2-3 meters.

If plants are planted near buildings, the distance between them and the walls is 1.5 meters.

Watering

Since rhododendrons are planted in loose soil, from which moisture quickly evaporates, they need to be watered frequently.Plants especially need moisture during the formation of flower buds. The water is pre-settled and heated, otherwise the roots of the plant may be damaged. In dry weather, you need to spray plants (especially young ones) along the crown.

Feeding

In order for rhododendron to bloom profusely, it needs to be fed several times a season.

Deadlines

They begin to feed the bushes in early spring with nitrogen fertilizers. They contribute to the growth of green mass. Later, during the summer, they are watered with fertilizing with a predominance of phosphorus and potassium. In autumn, rhododendrons grown in the Leningrad region are not fed, as they can grow young shoots that are unable to survive the winter.

Selection and dosage

As a nitrogen fertilizers in the spring apply urea or saltpeter in the following dosage:

• 1 matchbox of substance;
• for 10 liters of water.

5 liters of fertilizer are poured under a young bush, 10 liters are poured under an adult plant. Another feeding option:

• 1 part cow dung;
• stir in 15 parts water.

The mixture is infused for a week, then poured under the root of the plantings. Feeding is done once every 2 weeks. From mid-June, the bushes are watered with complex fertilizer with a predominance of potassium and phosphorus according to the instructions.

Note! Before using fertilizer, the root system of rhododendrons must be moistened with water.

Preparing for winter

Despite the frost resistance of many varieties, rhododendrons grown in the Leningrad region must be covered.

Watering

Toward the end of summer, watering is reduced, but before the onset of persistent frosts it resumes. The procedure is carried out for the reason that roots saturated with moisture will more easily endure the frosty winter. If there is heavy precipitation in the form of rain, additional watering is not performed.

Mulching

After abundant watering, the bushes are mulched with bark, nut shells, and cones. Their root system is located widely under the soil surface, so a large area of ​​the tree trunk circle is covered with mulch. The cover layer for young plants is 6-10 centimeters, for adults – 15-20 centimeters.

Shelter installation

When frost sets in from -10 °C, rhododendrons are covered with non-woven material folded in 2 layers. To prevent snow from accumulating and breaking young plantings, it is better to install the shelter in the form of a cone or pyramid, using a frame made of twigs.

In case of too much frost, spruce spruce branches are additionally used.

Trimming

In the spring, before the start of sap flow, sanitary pruning rhododendrons. In this case, broken, dried out, diseased branches are removed. A sharp pruner is used for the procedure. The cut areas are covered with garden varnish.

During formative pruning, poorly located shoots are removed and weakly developing side branches are shortened. The procedure promotes abundant tillering of rhododendrons. You can rejuvenate plants by radically cutting off all branches at a height of 30 centimeters from the ground surface.

Reproduction methods

You can grow rhododendron on your site in 3 ways: seeds, cuttings, layering.

Seeds

To grow seedlings, you must complete the following steps:

• Place drainage at the bottom of the planting container;
• pour the substrate you prepared yourself or soil for azaleas purchased at a flower shop on top;
• spread the seeds over the surface, sprinkle them with sand;
• cover the structure with plastic film or glass.

Caring for seedlings involves watering as needed and ventilating the mini-greenhouse.When the first shoots hatch, the cover is removed.

Cuttings

Propagation by cuttings is carried out as follows:

• the stems are cut into pieces of 5-8 centimeters;
• the lower leaves are cut off;
• the lower parts of the sections are placed in a growth stimulator solution for 12-16 hours;
• cuttings of rhododendrons are planted in boxes with a peat-sand mixture;
• The planting box with stems is covered with film.

When roots and young shoots form on the cuttings, they are transplanted into separate containers. In the fourth year of life, the seedlings are transferred to open ground.

By layering

Reproduction of rhododendron by layering step by step:

1. In spring, bend the lower shoots to the ground and secure the points of contact with pins or bent wire.
2. Sprinkle soil on top and water.
3. Tie the upper part of the layer to the support.
4. In the winter, cover the pinning area with mulch and spruce branches.
5. When the cuttings take root, separate them from the mother plant and plant them separately in a shady place.

After 2 years, the grown plant is transplanted to a permanent place.

Protection from diseases and pests

If overwatered, rhododendrons can become rotten. To prevent diseases in the spring, plants are sprayed with copper-containing preparations. Affected bushes are sprayed with fungicides. If the rhododendrons are too damaged by rot, they are dug up and burned.

The plantings can be favored by insects: spider mites, whiteflies, false scale insects, thrips. Insecticides and acaricides are used to control pests. Gastropods are destroyed with molluscicides or collected by hand.

Important! When working with chemicals, you must use gloves, goggles and a respirator.

Landscape Design Ideas

Beautiful flowering shrubs combine with many green spaces. For example, they will look spectacular next to conifers. Tall varieties are planted as a background for shorter decorative deciduous shrubs. A single growing bush against the background of a lawn will also look beautiful.

Reviews

According to gardeners, rhododendrons in the Leningrad region can grow and bloom safely, you just need to choose frost-resistant varieties. A correctly selected planting site and careful care during the season are the conditions under which plants will grow in the same place for a long time, delighting others with their spectacular flowering.

Olga Ivanovna, Svetogorsk

“I am a beginner gardener. I didn’t know that rhododendrons needed to be covered for the winter, and in the first year several branches froze. The next year, I carefully covered the entire plant. The rhododendron survived, and by the end of summer I already had a beautiful, overgrown bush.”

Elena, Vyborg

“I purchased 3 rhododendron bushes. One of them died. Most likely because I planted it in the wrong place. The area where this bush grew was very windy. The remaining plants were protected from the north by the wall of the building, so they developed well over the summer.”