HYDRANGEA

HYDRANGEA

Hydrangeas are plants of oriental origin that arrived in Europe at the beginning of the 1700’s thanks to the French botanist, Philibert de Commerson, who named them in honor of Hortense Nassau, daughter of the Prince of Nassau. The name of the genus, Hydrangea, derives from the Greek hydros = water and angeion = jug, because of the shape of the capsules that contain the seeds. The name also reflects the plant’s great need of water; it can consume dozens of liters of water a day. There are more than 80 species of hydrangeas, all of which require shade or part-shade. Some are evergreen, others are deciduous. The species are distinguishable by the development of their branches which can be shrubby or climbing. The latter have deciduous leaves and are very resistant to the cold. Hortenias require moist soils rich in humus, with an acidic pH. The composition of the soil and its acidity are very important for their growth and also for determining the colour of the flowers. Pink flowers can turn blue if the soil becomes particularly acidic. To artificially obtain this blue colour, one can add aluminium sulphate to the soil, through irrigation. In locations with mild winters, hydrangea plants can also survive outdoors, but must be protected under a mound of dry leaves. In order to bloom, they must, in any case, remain for a period of time in the cold (from 6-8 weeks at temperatures below 5°C), which induces the buds to produce flowers the following spring. Hydrangea plants must be watered frequently and thoroughly so as to avoid stress due to dehydration. They must be fed monthly, with complex soluble fertilizers, through irrigation. They are quite resistant to disease, but preventive treatments with copper and sulfur are useful in avoiding fungal diseases. Use simple aphicides to ward off aphids or butterflies.

pianta da fiore ortensia