What it is and features
Pervinca fiore is the Italian name of Vinca minor, a perennial herbaceous species of the Apocynaceae family. Typical of Europe and Asia Minor, and naturalized in North America, it is widespread in the Italian peninsula along the hedges, in cool and shady areas from the sea to the mountains. Its stems, emerging from a long rhizome, creeping and lying down, have simple, elliptical-lanceolate leaves, dark green and shiny. It flowers from February to June and appears among the first early species as soon as winter ends. Periwinkle flower loves moisture, but they do not live well if the growing soil is wet. Consequently, in the warm season it is advisable to carry out frequent waterings, without however creating stagnant water or soaking the soil. In winter it is necessary to suspend or reduce the water supply based on the climate.
How to grow it
The Periwinkle flowers, inserted in the axil of the leaves, are of a typical blue color called periwinkle blue: in many cases the nuance of the corolla turns into pure white or darkens towards the violet. The Periwinkle regular flower is tubular with five lacinias cut obliquely in a completely characteristic way. The fruit consists of two independent follicles. Periwinkles are widely cultivated in gardens, especially in the Vinca minor species, with flowers 2 cm in diameter. Vinca major is also cultivated, with flowers 4-5 cm in diameter, and Vinca difformis, whose flowers have an intermediate size compared to those of the other two species. The plant must be grown in a sunny area or at most with a partial shade exposure; moreover, it does not fear the cold.
The soil and fertilization
The Periwinkle flower grows without problems in any drained soil, even if it prefers a slightly acid substrate. It is advisable to add woodland and peat to the leaf mold and to avoid sandy and too dry soils. The results are obtained with a moist, light, medium-loose soil rich in nutrients. Fertilizing plants belonging to this species is not a necessary operation. At most you can spread granular fertilizer for flowering plants at the end of winter. Alternatively liquid fertilizer can be administered every 15 days over the same period of time together with the water to water. It is advisable not to add too much nitrogen fertilizers because they can cause scanty blooms and too much vegetation.
Periwinkle flower: Common species and parasites
In the gardens there is also Vinca herbacea, a species of south-eastern Europe. In the greenhouses is common Vinca rosea, of African origin, which can be kept outdoors by us only in southern Italy. The Vinca minor variety is also endowed with medicinal properties: the leaves and young stems contain astringent principles and are used in the treatment of dysentery and congestion. The Periwinkle flower can be attacked by rust, which causes reddish spots on the leaves. The leaves can also be affected by the red spider, which causes them to turn yellow and die: defoliation has a noticeable effect on the aesthetic appearance of the plants, however it is good not to use acaricides. In fact the parasites are hardly eradicated and the problem occurs again the following year. For this reason it is good not to place the Periwinkles near roses and other sensitive plants.