It is a floral species that over the centuries has been studied to be modified in search of a simple and resistant species to cultivate in pots, giving life to different shades of color and different shapes and sizes of leaves and petals.
The color of the petals varies depending on the acidity of the soil, when the PH is between 4 and 5.5 the acidity is high and the color of the petals takes on different shades of blue, the acid component in fact allows the plant to absorb the aluminum present in the soil (if it is not naturally present in the soil it can be modified during the preparation of the soil and fertilization). To maintain the blue color, it must be watered with rainwater and possibly add a blue hydrangea compound that contains easily assimilable aluminum from the roots of the plants.
When the PH is between 6 and 6.2 the soil's acidity is particularly low and the assumed color is between pink and red, even in this case the color can be maintained by adding a specific product to the water for watering. for pink hydrangeas.
It is therefore possible to vary the color to obtain the desired color by appropriately modifying it with fertilizers and by giving certain chemical substances to the soil where the hydrangeas are grown, but always acting gradually.
The hydrangeas grow best in acid soils whose pH is between the values of 4 and 6. The acidity is not modified by water, as long as it is the rain that is always the ideal solution for the development of shrubs.
The appropriate climatic conditions and the terrain
The hydrangeas find their optimal location in the Mediterranean areas, where the climate is mild and the cultivation is not particularly difficult even for the little experts in gardening. These flowers, in fact, despite being resistant, fear both excessive heat and frost. It is therefore necessary to try, in case you want to cultivate in particularly hot areas, to place them in an area protected by the shade so that they do not suffer too much from the heat and that they do not receive sunlight directly because they would risk their leaves burn themselves. If instead they are grown in areas that reach cold temperatures, it is good to place them in a small greenhouse so as to protect them from frost and atmospheric agents. It is therefore necessary to keep the hydrangeas in a mild climate, with intermediate temperatures, in a cool area and with a good degree of humidity.
Even the soil must be prepared appropriately: the ideal condition is a medium mixture, rather soft, mixed with peat and abundantly fertilized. It is therefore necessary to proceed with a vigorous digging of the soil to aerate it and make it soft, then add gravel or pebbles that improve the drainage capacity of the soil and finally you can add to the more superficial layer (about half a meter) the manure or compost to increase soil fertility.
If the cold season is approaching it is advisable to proceed with mulching to protect the plant from the rigors of winter: you can cover the area around the plant with dry leaves or straw, but also with plastic material previously drilled to allow the soil to breathe and receive water. If you choose traditional mulch the compound of leaves and bark during the winter will be important both from the nutritional point of view and in preventing the growth of grass or other unwanted plants.
With the arrival of spring you need to fertilize the soil, using preferably mineral fertilizers to buy from specialist retailers who will advise you on the product to choose.
Planting and watering operation
To be sure that the hydrangea plant grows healthy and lush it will be appropriate to decide to plant young seedlings purchased directly from a nursery, the most suitable periods for planting are late spring (especially the month of May) or beginning of autumn (late October, early November) because the climate is mild and the rains are abundant and ensure optimal climatic conditions for hydrangeas.
The dwelling can be arranged for the plant by digging a hole for each plant with the spade, taking into account the volume occupied by the root system and abounding in every direction, the size should be about twice the size of the plant both in width and in depth. On the bottom of the hole you can place a fair amount of manure, then the plant must be inserted with care, covered by adding sand that favors the right humidity of the soil, the soil should be slightly compacted and abundantly watered. Around the branches of the bush it is good to keep an area of bare (or mulched) soil where no grass should grow, which would take away nutrients and water from the plant.
Hydrangeas need a very humid environment even if, like most plants, they fear stagnation. Therefore it is good that the soil is always moist and that the waterings are not very abundant but frequent, to avoid stagnation and maintain the humidity of the soil at a constant level. The hydrangea plant needs abundant watering especially in the period in which the buds are formed, while after flowering it must be watered less abundantly to preserve the freshness and beauty of the flowers.
Pruning and pests
For a correct cultivation, the hydrangeas must be trimmed after the flowering period, in late September or early October: you can use a pair of sharp and previously disinfected gardening shears and make a clean and sharp cut at an angle below the now dried flower.
Hydrangeas are resistant plants but can be victims of diseases and pests. The diseases to which they are particularly prone are mold and mildew if the soil does not drain the water properly, in more serious cases there is also the risk of root rot that would completely compromise the health of the plant. In addition to intervening during the preparation of the soil, fungicides can be used to eradicate molds, after eliminating the areas damaged by mold with a clean cut.
The most common parasites are aphids, mealybugs and mites: they must be eliminated manually and then the insecticide must be applied to avoid the recurrence of the problem. Some time after having carried out the pesticide treatment, the leaves must be washed to eliminate the residues that the insects leave on the plants, such as their cobwebs, for this operation there are specific products suitable for plants.