The Rudbeckia is a beautiful large perennial, native to North America, where about twenty different species develop; in the garden, in general, Rudbeckia hirta and Rudbeckia bilobata are grown, as well as the hybrid varieties produced over the years. It is a perennial that develops large clumps of leaves, arranged in a spiral, lanceolate, whole or lobed, dark green, with showy veins. Between the leaves, throughout the summer and most of the autumn, thin little stems develop, which carry large daisy-shaped flowers; the rudbeckies belong to the family of asteraceae, and therefore their flower is a flower head, or an inflorescence made up of hundreds of tubular flowers, of dark brown color, with a wreath of flowers around them that present a single large elongated petal, yellow gold. The flowers of rudbeckia they are arranged in a cone, since the central circle of the flower head is arranged in the form of a tiny hill, and the outer petals are generally turned downwards. Each plant produces more flowers during a season, and it also tends to increase the amount of leaves, giving rise to a real spot of color.
Rudbeckies are quite cultivated in Italy, but are widespread in European and North American gardens, precisely because of their prolonged flowering, which continues until the autumn cold, giving the garden a golden accent. There are numerous cultivars of rudbeckia, some of which are particularly compact, which do not exceed 20-30 cm in height (rudbeckia hirta can exceed eighty cm in height), others with flowers of particular colors, such as orange or red , or with petals that have flaming or zoning in a contrasting color.
These plants lend themselves well to running wild, especially in low-maintenance areas of the garden, or along road beds. They love bright and sunny positions, but in the Mediterranean areas, characterized by a decidedly torrid summer climate and strong sea winds, it is advisable to look for a semi-shaded position for the rudbeckia, so that they can enjoy a few hours of refreshment from the warm sun of July.
They are not afraid of frost, as at the arrival of the most intense cold they tend to lose the aerial part that will return the following spring; they can therefore easily find a place directly in the flower beds, or on the vases of the most exposed terrace.
They prefer a soil not necessarily very rich in organic material, but very well drained, so that the water does not tend to stagnate, causing the proliferation of mold, fungus and rot. Therefore, in the first year after planting, it is watered fairly regularly, whenever the soil is dry, especially in summer; in the following years instead it is watered only in case of prolonged drought. It is not necessary to water these perennials during the cold season.
The rudbeckie do not like excesses of mineral salts in the soil, which tend to favor the development of thin and not very strong stems and of elongated and sparse plants; therefore generally it is avoided to supply the fertilizer, except to slightly enrich the soil at the end of winter, with little manure or earthworm humus, or even with a pass of fresh universal soil.
The care to be given to the plants is minimal, even during flowering, except for removing the withered flowers, to prevent them from going and seed, thus ending the flowering season.
Rudbeckie from seed
Typically rudbeckia seedlings are already well developed in the nursery; but if we wish to revive a large flowerbed, we can also obtain these beautiful perennials even from seed. We can sow directly at home, in the spring, when the minimum temperatures are above 10-12 ° C; but first we will have to work the soil well, lightening it with sand if we think it is too clayey.
The rudbeckie are obtained from seed even during the winter months, to have seedlings already well developed in March April; before sowing them it is good to place the seeds in a bag with little sand, and then in the refrigerator for at least a month, to simulate the winter season, and stimulate the germination of the seeds. Afterwards the seeding tray is kept in a warm place and again, until the spring season is felt, allowing us to place the seedlings outdoors.
Rudbeckia and echinacea
Echinacea is an asteracea that was once assimilated to rudbeckia, and which today has instead been divided into a different genus, always belonging to the family of asteraceae. Echinacea looks very much like rudbeckia, except that its flowers are red or pink or purple, colors that do not belong to the rudbeckia genus. Echinacea, and also rudbeckia, enter many herbal products, which use their leaves and roots.
In particular, echinacea products were used in ancient times by American populations to prepare healing pastes; modern studies and the use in herbal medicine instead testify as the echinacea extract, as well as the infusions based on flowers and leaves of this plant, which are very useful in decreasing the symptoms of the cold, even when these are chronic or particularly strong .