We call perennials herbaceous (not forming woody stems), which have the capacity to renew the above-ground and underground parts of certain permanent bodies annually.
This group includes a great number of plants of different genera and species, differing in height, habit, foliage, shape and color of flowers. The use of perennials in green areas and home gardens is enormous. You can create groups from them, discounts, rock gardens etc.. Perennial beds can be decorative throughout the growing season, because plants can be so selected, that they bloom in different months.
The use of perennials is also more cost-effective than the use of annuals or biennials, because they can grow in one place for several, and even a dozen or so years.
Propagation of perennials. The most common permanent organ among perennials is the stem which renews every year. It usually forms at the base of the old stem, which dies with its root system at the end of the growing season (e.g. boroughs), and the shoots at its base produce their own root system. In this way, "independent" plants are formed. The reproduction of such perennials is very easy and consists in separating the emerging plants. Often, the newly emerging plants are fused with each other at the base of the shoot (aster, pyrethrum), the death of which may take several or several years. In such cases, obtaining more plants requires breaking up or cutting open the dense clumps thus formed. Dividing these types of perennials is easier if they produce long underground shoots, the so-called. runners, like for example. lily of the valley or some asters. Growing such perennials is easy. Thanks to the high ability to restore the root system, they are capable of strong growth and full development already in the first or second year after planting.. Therefore, these perennials can be transplanted and separated more often.
Another permanent organ that is often found in perennials is the root, which produces buds at the top, from which new above-ground shoots grow every year. These shoots can produce adventitious roots, like for example. peony, or lupine, or use only a durable and poorly branching mother root for several years (like for example. gypsophila, mak). The reproduction of such perennials by division is more difficult and less efficient, therefore, they are more often propagated by seeds or shoot cuttings.
The cultivation of this type of perennial is slightly different. The limited ability to form the root system does not allow for rapid growth and development of these plants. They usually reach their full development after several years. These plants cannot be replanted too often, and the place of planting must be carefully prepared and so fertilized, to provide plants with a sufficient amount of food for several or several years.
When propagating perennials by sowing, seeds are sown in frames or in wooden boxes in the multiplier, and when they reach a height of several centimeters, they are dropped off in the nursery.
Some perennials are planted directly into the soil, most, however, are planted in the inspection, and after rooting it is transplanted into nursery beds.
The methods and dates of propagation of perennials of particular types are given in the table.
