Most types of hydrangea grow in warm, humid climates. For summer residents of the middle zone, varieties of serrated hydrangea became a discovery. A frost-resistant species with bright, long-lasting flowering will decorate a hedge, patio, and create a composition with other shrubs, evergreens and decorative foliage plants. Flowers in delicate blue, pink and white tones are suitable for bouquets and remain fresh for a long time when cut.
What kind of plant is this
Hydrangea serrata is a low-growing garden shrub. In nature, it grows in the mountain valleys of Japan and Korea. Plant characteristics:
| Sign | Description |
| Type | Deciduous |
| Form | Round |
| Height and width | 1.2 meters |
| Leaves | elongated,
oval, jagged at the edges, pointed at the end, 15 centimeters long, dark green. |
| Branches | Upright |
| Flowers | The inflorescence is surrounded by large flowers |
| Fruit | Seed pods |
Hydrangea drankLachata blooms from June to September. Small flowers of inflorescences participate in pollination. The four-leaf large flowers along the edges are sterile. The branched roots of the plant penetrate 40 centimeters deep into the soil. The shrub is resistant to frost down to -20 degrees.
Varieties and varieties
The main decorative value of serrated hydrangea is its unusual flowers in delicate tones. Large inflorescences up to 8 centimeters in diameter give the garden a charming blue, pink, white, purple or variegated glow.
The color of the petals depends on the variety of serrated hydrangea. There are more than twenty of them in total. Some bloom with two-color flowers, but are not the result of selection.
All exotic varieties are found naturally on the Japanese islands from northern Hokkaido to southern Kyushu, as well as on the island of Ulleungdo in South Korea. Four varieties have become the most popular and adapted to the Russian climate.
Santiago
Compact bushes grow up to only 80 centimeters in height. Hydrangea Santiago flowers resemble pink lace.
Advantages of the variety:
- flowering begins in June; and continues until September;
- decorates flower beds and paths;
- The green leaves in summer take on a fantastic red hue in autumn.
Hydrangea variety Santiago grows well in lightly shaded areas. Its disadvantages:
- you need to carefully monitor soil moisture, does not like dampness;
- bushes must be covered for the winter if the temperature drops below -20 degrees;
- The variety is sensitive to soil acidity.
If the soil pH is high, the hydrangea will bloom blue flowers instead of the expected pink ones.
Bluebird
A bush with graceful branches grows a meter in height and produces flowers of cool shades: the inflorescences change from violet-blue to red-lilac towards the end of flowering, and the large lateral ones remain blue.
Advantages of the variety:
- abundant flowering at any age;
- fills the garden with a honey-sweet aroma;
- universal for garden compositions.
Hydrangea of a blue-violet hue will decorate the space around the house, gazebos, and hedges. In Japanese it is called "Ajisai" - "purple flower-sun"
Cons of the Bluebird variety:
- the flowering period is shorter, beginning at the end of July;
- less frost-resistant.
The serrated variety will survive winter in temperatures above -20 degrees outdoors. But in regions with a harsher climate, the bushes will need shelter.
Koreana
The tall variety reaches 150 centimeters in height and has a spreading crown. The main shades of colors are white and pink.
Advantages of Koreana:
- from one variety you can get bushes of different colors, from white to blue;
- Resistant to frost down to -25 degrees.
The Koreana variety is unusual in that the color of its petals can be adjusted by adjusting the acidity of the soil. The more acidic the soil, the darker the petals become.
Disadvantages of the variety:
- if experiments with color were not part of the plans, there is a risk of not guessing the shade of the flowering shrub when composing the composition;
- low resistance to drought.
The Greek name for hydrangea “hydrangea” means “vessel of water”, and in Japan this flower is also called “yearning for water”. Koreana lives up to both names and needs plenty of water.
Preciosa
An even taller variety is suitable for arranging hedges. The height of Preciosa reaches 2.5 meters. The bushes change color during the flowering period: the leaves change from green to burgundy, the flowers turn from lime to pink and then to crimson.
Pros of tall hydrangea:
- early flowering, blooms in June;
- bright variety.
The color of the petals becomes deep red if the bushes are planted in soil with high acidity.
Disadvantages of the variety:
- low frost resistance;
- needs pruning.
If the temperature drops below -20 degrees, Koreana needs to be wrapped. Without thinning the branches, the bushes grow and look sloppy.
Landing instructions
Hydrangea serrata can be planted in open ground or in pots. The plant is suitable for nutritious soil with neutral, weak or high acidity. Hydrangea is sensitive to soil conditions thanks to its wide branched root system, so it quickly changes the color of its flowers.
A favorable time for planting serrated varieties is early spring. In southern regions with mild winters, the plant is planted in September. Young specimens ready for planting have 3-5 developed flexible shoots with smooth leaves without flaws.
Selection and preparation of a site
An open area of the garden with partial shade is suitable for Japanese shrubs. Moisture-loving varieties can be planted next to tall trees, but they will take away nutrition from smaller plants.
Suitable soil for hydrangea is moist, slightly acidic loam.The shrub is planted in a mixture: two parts each of humus and compost, one part each of sand and peat. Additionally, the soil is fertilized with urea. To reduce acidity, the site is dug up with dolomite flour, crushed chalk, and wood ash. Lime should not be used due to its adverse effects on the plant.
How to make holes
Serrated hydrangea bushes are planted at a distance of 1.5 meters from each other. The depth of the planting hole depends on the volume of the seedling's earthen coma, approximately 35-60 centimeters.
Well preparation:
- dig a hole measuring 50x50 centimeters in pre-fertilized soil;
- mix the extracted soil with the prepared nutrient mixture;
- pour a layer of gravel or crushed stone 15 centimeters thick at the bottom of the hole for drainage;
- Place a third of the nutrient soil mixture on top.
The remaining mixture will be needed to fill the hole with the seedling. It is necessary to lay a narrow channel around it for irrigation, through which moisture will flow to the branched roots.
Planting process
Before planting, the root system of serrata hydrangea seedlings must be closed. The earthen coma retains the moisture and nutrients that the plant initially requires for adaptation.
How to plant Japanese bush:
- carefully shake out of the pot along with the earthen lump;
- install vertically in the hole so that the root collar is 3-5 centimeters above the soil level;
- fill the hole with soil mixture.
The procedure is completed with watering. A bucket of water is used for one seedling. To retain moisture longer, the soil is mulched with sawdust or pine needles. The mulch layer is 10 centimeters.
Aftercare
The main difficulty in caring for serrata hydrangea is timely watering.In addition, it is important to ensure that the plant is not exposed to direct sunlight for a long time. The health of the exotic Japanese bush depends on the balance of moisture and sun, as well as on proper wintering and pruning.
Watering
Serrata hydrangea needs to be watered daily. The more sun there is in the area where the shrub grows, the more moisture it requires. With sufficient moisture, the plant will feel good in the heat. Dry soil is harmful to roots. From the heat, the flowers fade, and the leaves curl and become stained.
Watering mode:
- at temperatures up to +25 degrees - in the morning and evening;
- at temperatures of +25-30 degrees and above - water additionally during the day, when the sun passes its midday peak.
One bush requires 2-3 buckets of water at a time. In the first year after planting, one bucket is enough for seedlings.
It is better to take water for irrigation from a spring or purify tap water. Hydrangea serrata is sensitive to chlorine.
To reduce water consumption, plants can be artificially shaded by installing a removable awning. Mulching will also help retain moisture, but then the soil in the tree trunk circle must be loosened periodically. On rainy days, the bush does not need to be watered.
Top dressing
Serrata hydrangea is suitable for organic and mineral fertilizers. The plant is fed in the spring after awakening, in the summer during and in the fall after flowering.
How to feed a bush:
- in the spring, add an aqueous solution of bird droppings prepared in a ratio of 1:20 to stimulate the awakening of the buds and the rapid formation of leaves;
- during the period when buds appear, in June or July, depending on the variety, a phosphorus-potassium solution is prepared - 30 grams of superphosphate and potassium salt are diluted in 10 liters of water;
- during the flowering period, 2 grams of boric acid are added to the mineral solution;
- After flowering is completed in September, fertilizer is applied to the soil - 50 grams of potassium salt and superphosphate in each trunk circle.
To develop foliage, serrata hydrangea is fertilized with nitrogen from mid-spring. But two weeks before the buds appear, this mineral should be gradually excluded from feeding. An excess of nitrogen negatively affects the flowering of the plant.
Pest Control
Hydrangea serrata suffers from chlorosis and late blight. Both diseases are infectious and are transmitted by insects. Plant pests:
- slugs, snails;
- spider mite;
- scale insect;
- grape weevil;
- aphid.
To combat insects, the insecticides “Fufan”, “Tifos”, “Akarin”, “Apache” are used.
Serrata hydrangea is vulnerable to fungi: powdery mildew, gray mold, root rot, fusarium. To prevent fungal infections, it is recommended to treat the plant with fungicides, for example, Alirin. Controlling soil moisture and crown growth will help preserve the health of hydrangeas.
Preparing for winter
Insects and mold often grow in untrimmed shrubs. Therefore, serrated hydrangea, especially tall varieties, must be pruned.
Sanitary pruning is carried out in the spring: broken and non-viable branches are removed. The shape of the bush is also maintained and growth is stimulated - the branches growing inside are cut off and the top is shortened.
Young seedlings and less frost-resistant varieties of serrate hydrangea are covered for the winter:
- they place supports around the bushes and cover them with agrofibre on top and sides;
- covered with spruce branches;
- Lay out a layer of mulch 25 centimeters thick.
In regions with mild winters, mulching will be sufficient for mature plants.It is recommended to tie branches of bushes growing in open areas to the trunk with twine so that they do not break due to snow and wind.
