Cultivation and management techniques of hydrangea

Water and fertilizer management

Hydrangeas like fertilizer and should be fertilized with decomposed thin cake fertilizer water once every 15 days during the growth period. To maintain the acidity of the soil, 1%-3% ferrous sulfate can be added to the fertilizer solution. Regular watering with alum fertilizer can make the plant luxuriant and leafy; applying potassium dihydrogen phosphate 1-2 times during the bud formation period can make the flowers larger and more colorful; applying cake fertilizer should be avoided in the dog days to avoid attracting diseases and pests and damaging the root system.

Hydrangeas have lush branches and leaves and require a lot of water. During the growing season of spring, summer and autumn, you need to water them enough to keep the soil in the pot moist. The weather is hot in summer and the evaporation is high. In addition to watering the plants sufficiently, you should also spray water on the leaves every day. Hydrangea should not have water accumulation in the pot, otherwise the roots will rot. After entering autumn, gradually reduce the amount of watering.

Four seasons maintenance

Hydrangea prefers semi-shaded and humid environment and is not very cold-resistant. Avoid direct sunlight during the hot summer, otherwise the leaves will easily burn and turn yellow, and the branches and leaves will wilt and wither after frost. The above-ground parts of the plants will die in winter when cultivated in the field, and new shoots will sprout from the rhizomes and bloom again the following year. If they overwinter in potted plants in a greenhouse, they can remain evergreen.

Key points for spring maintenance: For potted plants, dead branches should be pruned and the pots should be repotted and the soil changed. After the plants have adapted to the pots, one or two applications of thin liquid fertilizer mainly containing nitrogen fertilizer can promote the germination of branches and leaves.

Maintenance tips in summer and autumn: It should be placed in semi-shade or under a curtain shed to avoid direct sunlight to prevent the leaves from turning yellow and burning. Apply top dressing once or twice before and after flowering to promote green leaves and abundant flowers. After the flowers fade, the flower stalks should be trimmed in time to maintain a beautiful appearance. The potting soil should always be kept moist, but water should be prevented from accumulating after rain to prevent the fleshy roots of the hydrangea from rotting due to excessive water.

Key points for winter maintenance: After winter, plants grown in the open field should be covered with soil to keep warm so that they can safely overwinter; potted plants can be placed in a warm place facing south, sunny and without cold winds. Although the leaves fall off in winter, the roots and branches remain alive, and new leaves sprout the following spring.

Soil replacement and pruning

Potted hydrangeas generally need to be repotted and the soil changed once a year. It is best to repot and change the soil in early March. When repotting, the roots of the plant should be pruned, and rotten roots, dead roots and excessively long roots should be cut off. After moving the plant to the new pot, compact the soil, water it thoroughly, place it in a shaded place for about 10 days, then move it outdoors for normal management.

To make the crown of the potted hydrangea beautiful and produce more flowers, the plant needs to be pruned. Generally, after the seedlings survive and grow to 10-15 cm in height, they should be topped off to allow the lower axillary buds to germinate. Then select the 4 new branches in the middle and upper parts after they have sprouted, and remove all the axillary buds at the bottom. When the new branches grow to 8-10 cm, pinch them for the second time. Hydrangeas usually bloom on two-year-old strong branches. After flowering, the old branches should be cut short, leaving only 2-3 buds, to limit the plant from growing too high and promote the growth of new shoots. In autumn, cut off the top of the new shoots to stop the branches from growing and facilitate wintering. After such pruning, the plant shape becomes more beautiful, greatly enhancing its ornamental value.