The genus chrysanthemum hyb. it has dozens of species of herbaceous plants, generally perennials, originating from Asia and Europe, many of which are cultivated for their flowering. They belong to the genus Chrysanthemum hyb. also many species of daisies and asters, and in general most of the herbaceous plants that produce flat flowers, with many colored petals and a golden center. The flowers that are commonly called chrysanthemums they arise from the crossing between two species native to Asia: c. Moriifolium and C. indicum; over the years, from the crossing of these wild species, and the varieties derived from them, dozens of varieties of chrysanthemum have been obtained, even some with flowers of particular shape; for example we mention i chrysanthemums pompons, which have spherical inflorescences, with an almost absent central disc, and spider chrysanthemums, with very elongated and disordered lateral petals. Generally speaking, they are easy to grow plants that bloom in early autumn when temperatures are already cool. In Italy they are used a lot as flowers for the dead, so unfortunately they are not appreciated by everyone, although they are certainly flowers of rare beauty; in any case they should not be missing in the garden of those who want flowering plants even in autumn. To obtain large flowers and dense bushes it is advisable to trim the plant several times and remove some of the lateral shoots.
History and botany of chrysanthemums
The genus "Chrysanthemum hyb." it includes about 37 species of plants originating mainly from East Asia and Europe. They belong to the Asteraceae family.
In their spontaneous state, these are perennial herbaceous plants or small bushes that can reach more than 1 meter in height. The leaves are lanceolate, lobed and usually give off a scent, sometimes pleasant, others less so. Their large flowers, generally in the shape of a daisy, can be white, pink or yellow and usually appear during autumn.
The cultivation of this flower originated in China about 2500 years ago. It arrived in Europe in the seventeenth century and was baptized chrysanthemum which from the Greek means "golden flower". In fact, the species native to Europe often have flower heads of that color. In the 19th century, its cultivation spread to the whole continent and also spread to the Americas. In temperate countries they are grown outdoors, as garden plants. In the northernmost areas, however, they are considered more cut flowers and are grown mostly in greenhouses.
Exposure and temperatures
The specimens of Chrysanthemum hyb. they are grown in a sunny place, they do not fear the cold, even if very harsh winters can damage the leaves; from the clump of roots in spring new leaves will start to develop again. Since many varieties produce very long flower stems it is advisable to plant the chrysanthemums in a place sheltered from the wind. Chrysanthemum prefers mild climates with temperatures ranging from 16 to 18 ° C. Some are very rustic, others can withstand a maximum of 7 ° C at night. Frosts generally result in the complete loss of leaves, but they are often capable of producing new ones, if the climate permits. However, around 7 ° C the leaves usually turn yellow in a conspicuous way.
If grown indoors, they must be kept in a bright, airy area, but away from cold currents. If the light is poor, the flower buds will not open, but will fall off after drying.
From mid-spring it is absolutely better, if possible, to move them outside (in the garden or on a balcony or terrace) until the end of September. In this way their flowering will be more beautiful and will last longer. If we want to put them directly in the ground we choose a site where there is a lot of direct light. However, if we live in a very hot and arid area, keep in mind that the sun could cause burns to the leaves. Consequently, it might be useful to evaluate a slightly more sheltered exposure. In general, in those conditions, the ideal position is the one that guarantees good lighting throughout the morning and more filtered during the early afternoon. We point out that it is always good to also carefully evaluate the specific needs of each cultivar because they can vary considerably.
in spring and summer water the Chrysanthemum hyb. from time to time, avoiding wetting the soil while it is humid; during the cold months water sporadically, only in the absence of rain; the potted specimens should be watered regularly, avoiding excesses. From March to October, provide fertilizer for flowering plants every 15-20 days.
chrysanthemums prefer loose, very well drained, soft and well aerated soils; it is advisable to add sand to the soil, to increase water drainage, and well-mature manure.
usually occurs by cuttings, in autumn or early spring; chrysanthemum branches usually root very easily, even directly in the home.
Parasites and diseases
The specimens of Chrysanthemum hyb. they fear root rot, powdery mildew and aphids.
- the cochineal. It can particularly attack the young stems of indoor plants, sucking their sap. They can be removed with cotton soaked in alcohol or by using systemic insecticides.
- thrips: they produce lesions on the leaves by pricking them. The remedy is a good insecticide.
- mites: they are positioned on the back of the leaf and make the whole individual less vital. They fight with specific acaricides.
The hybrids that growers have managed to obtain thanks to careful selections can boast much larger flowers than the spontaneous species, with more flower heads and with single, double, semi-double or ball corollas. The colors available on the market are truly innumerable and find everyone's taste: white, yellow, pink, red, golden, purple, lilac. In practice, there are all imaginable shades, except blue. Most are, as we have said, perennial. In many cases, however, they are used as indoor plants and are therefore considered as annuals. If grown outdoors, in the open ground, they can reach up to 1 meter in height. The same variety, kept in a container, will however reach a maximum of 40 cm.
Florists have the opportunity to sell them at any time of the year because forcing is not particularly difficult. In nature, they produce buds between autumn and the beginning of winter. However, this event can be anticipated or postponed by decreasing the hours of light to which they are exposed. This will mimic the plant's natural cycle that emits flower stems as the days get shorter, so dark hours prevail over light hours.
Soil and fertilization
Chrysanthemums prefer a slightly acidic soil whose pH ranges from 5.5 to 6.5. They also need excellent drainage to prevent root rot. In addition, an excellent supply of nitrogen and potassium is important. The first promotes vegetative growth, the second the production of flowers. In the ground they can be applied thanks to slow release granular fertilizers. Potted plants can be fertilized with a specific liquid product to be administered every 15 days throughout the vegetative period.
They need to always have a moist substrate. In any case, it is necessary to avoid excessive irrigation causing water stagnation: these are the most frequent reason for which rot and fungi arise in the root system and in the collar area.
If the soil is too dry, the first visible consequence is the loss of buds by drying out. At that point, however, it is difficult for them to emit them again and therefore to see them in bloom we will have to wait until the following year. It is therefore very important, especially in hot and dry climates, to carefully monitor the degree of humidity on a daily basis. If the plant is in a container, the best way to irrigate it is to place it in a tub full of water until the soil is well moist. Subsequently we will have to put it to drain on a plate. When all the excess liquid has been drained, we can move the jar onto a dry surface. If the plant lives in an apartment, in hot climates and with low ambient humidity, it would be good to vaporize it often with non-calcareous or, even better, rain water. In winter, especially if kept outdoors or in the open ground, it does not require regular irrigation as in this period it enters a phase of vegetative rest.
Reproduction and care
Chrysanthemums can also be sown directly in the home. Germination takes place within 10 or 20 days, depending on humidity and temperature.
The ideal one is around 15 ° C and therefore the ideal period is spring. However, if we live in a particularly hot climate (in the South and on the islands) it may also be possible to proceed with sowing during the autumn (perhaps in jars, to be kept sheltered). This will give us the possibility of having more developed and flowering plants already from the first vintage.
New seedlings can also be obtained by proceeding with cuttings in March. Healthy herbaceous stems should be cut into 6-7 cm long segments. The basal leaves are removed and a hormone product is distributed on the cut to facilitate the release of roots. They are then inserted into a very light compound of sand and peat or peat and perlite and kept at a constant temperature of 15 ° C and with a rather high ambient humidity. It is also important to place them in an environment free of drafts. As soon as the rooting has taken place (we will see an abundant emission of leaves) we can transfer the seedlings into individual jars. Usually the first flowering occurs in the following year. It is certainly very important to proceed with constant topping to obtain a well branched and full specimen.
For the care of all plants it is very important to constantly take care of cleaning by removing exhausted flowers. In this way, these vegetables will not waste energy feeding potential seeds and will instead return to produce other buds. Consequently, flowering will be longer and the specimen more vigorous.
-Oidium: produces whitish spots on the leaves and buds. It is prevented through sulfur and fought with specific products
-Botrytis cinerea (gray mold): a gray and brown patina is created on the stems and buds. To prevent it, we must avoid wetting the vegetation and placing it in an area that is too shady. It is also possible to use cupric or, in cases of severe attacks, curative and eradicating fungicides.
-Rust: causes red spots when temperatures are very high. We use specific products.
-Fall or dryness of the buds: probably due to lack of water or light. We cut and expose more to the sun.
-Dry leaves: little watering or too cold water.
- Leaves smaller than normal: too many or too few irrigations. Lack of nitrogen, caterpillars, various insects or viruses.
- Too long branches, light green or white: lack of light
Other cultivation problems
-Fall or dryness of the buds: probably due to lack of water or light. Lack of nitrogen, caterpillars, various insects or viruses.
- Too long branches, light green or white: lack of light
Chrysanthemums - Chrysanthemum hyb .: Medicinal uses of chrysanthemums
European chrysanthemums have always been traditionally considered medicinal plants.
For example, from the leaves and flowers, dried in the shade, of C. vulgare (also called Tansy) tansy is obtained. This substance is very bitter and very toxic, but it was used for defense against roundworms and oxyurides. C balsamita is commonly called St. Peter's Wort. It is widely used in the kitchen for the preparation of omelettes and stuffed pasta. It is valuable as it contains an essential oil that promotes bile secretions. It is also useful against bronchial catarrhs. However, the most important chrysanthemum, both from a medical and an industrial point of view, is C. cinerariaefolium (also called Pyrethrum). It is spontaneous in the Balkans, the Americas and even Japan. An insecticidal powder is prepared with the flower heads. Contains the active ingredient pyrethrin capable of inducing paralysis and death in diptera and hymenoptera. It also has the undoubted advantage of being totally harmless to pets and humans. It is still one of the few insecticides allowed in organic farming today.