The genus Hibiscus belongs to the Malvacee family, and has hundreds of species, originating in most of the temperate and tropical areas of the world, from Europe to North America, from Asia to Australia. The term hibiscus refers to annual and perennial plants, evergreen or deciduous shrubs, and even small trees. In Italy the most cultivated species of hibiscus are Hibiscus syriacus, a medium-sized, rustic and deciduous shrub; and Hibiscus rosa-sinensis, a small evergreen shrub with large flowers.
The most known species
Very used in gardens, the Syriac hibiscus is a shrub of even large dimensions, which can reach 2-3 meters in height, sometimes cultivated also as a sapling; it is often used in street furniture, even in sea areas. It is a very rustic, deciduous shrub with light green, oval-shaped foliage; the flowers are white, pink or blue, simple or double, they bloom from late spring until autumn. The fruits are woody capsules, containing numerous seeds, often remaining on the plant even during the winter months; these plants are very easy to cultivate, they do not require assiduous care, and withstand cold and drought without problems. They settle in a sunny place, as poor exposure to sunlight could cause poor flowering. To obtain a well developed and vigorous shrub it is advisable to place it in a soft and very well drained soil, even sandy or stony; every spring I bury at the base of the stem of the organic fertilizer, or of the slow-release granular fertilizer. During particularly cold winters, in the colder peninsula areas, it may happen that frost causes the young plants to dry out, which generally sprout without problems when spring arrives.
During the winter the plants completely strip off the foliage; the young leaves begin to sprout quite late, in late spring, before they sprout, or even in autumn, let us remember to shorten the stems by at least a third of their length, so as to keep the shrub more dense and compact.
Hibiscus rosa-sinensis, is another species very much cultivated in Italy, and also in the rest of the Mediterranean area. It is a small, roundish, evergreen shrub, with beautiful, shiny dark green, shiny, oval-shaped foliage with serrated leaves. In the right climatic conditions it produces flowers throughout the year; in Italy it actually blooms only during the summer months. This plant fears frost, so it is grown outdoors only in the central-southern areas, while in the north it is kept outdoors only during the summer months, and brought back home during the winter. In fact it can also be used as a houseplant, provided you place it in a very bright place and away from sudden blows of air. In the garden it is placed in a sunny or partially shaded place. The flowering is spectacular, the flowers are large and of a very intense color; There are hundreds of hybrid varieties with yellow, red, purple, fuchsia, even double, striped and with contrasting color spots. The cultivation is quite simple, it is a plant that must be placed in a bright place, in fertile and very well drained soil; it is watered when the soil is dry, avoiding leaving the plant dry for prolonged periods of time; every 2-3 weeks we provide fertilizer for flowering plants.
Hibiscus: Other species
Some other species are commonly grown in Italy; in the aquatic garden we can place the hibiscus moscheutos, a plant that needs frequent watering, with bright green, deciduous foliage, which often turns red when cultivated in a sunny position; the flowers are large, red or bright pink. The flowering of the coccineous hibiscus is very showy, with deciduous, palmate, bronzed green shrub; in summer it produces enormous flowers with five petals, bright red; during the winter months the stems often dry out, to spring up again during the late spring.
In the rest of the world there are many cultivated species, also for commercial purposes, from some varieties of hibiscus they produce edible pulpy fruits, a raw material for the textile and paper industry. A curiosity, the karkadи, a typical North African drink, is produced using the leaves and flowers of the sabdariffa hibiscus.