Conditions necessary for forcing
Those who decided to master the pasture, should have an idea of the periods of development and recreation, following in the life of the plant one after another.
It is known that in the life of most biannuals or perennials a rest period is necessary. And part of this time plants "sleep", and at other times they do not develop due to unfavorable weather conditions - low temperatures, lack of light, etc. "Dream" of the first kind is called a deep calm, and the second - forced rest.
In order to interrupt forced rest it is sufficient to create favorable conditions, and in order to interrupt deep rest, it is necessary to apply special methods of treatment - carbon dioxide treatment, acid, warm irrigation, negative temperatures, etc.
The temperature can be considered the main factor influencing the blooming time.
The method of warm baths is used for forcing lilacs and other ornamental shrubs( forcing, peach, azalea, etc.).With this method, plants or their shoots, branches, stems are immersed in water with a temperature of 30-40 C for 9-12 hours.
The temperature and duration of exposure depends on the timing of forcing and plant species. For example, rhizomes of the lily-of-the-valley at the forcing in the beginning of November should be immersed in warm water for 12-14 hours, the water temperature should be 40 ° C, and if at the end of December a sufficient water temperature of 32 ° C is sufficient for forcing out the
.Warm water acts( interrupts rest) only on those shoots or parts of them that are subjected to the procedure. A variation of the method is forcing out by means of water vapor: the plants are placed in a greenhouse at a temperature of 43 SS and irrigated every thirty minutes. Such a high temperature is needed during the October forcing, and in January the lilies of the valley blossom already at a temperature of 28 ° C.
The method of cooling is used for forcing. This is one of the most common ways of interrupting the rest period, which is usually used for forcing bulbous plants.
In this case, forcing bulbs that are in a state of deep peace, for 2-5 weeks, placed in a cellar or refrigerator, which maintains a temperature of 0-5 ° C.The duration of this action depends on how deep the state of rest. The less time remains for the plant before the end of this period, the shorter the cooling time. When the deep peace is over and the plants pass into a state of forced rest, in order for them to blossom, it will be sufficient to simply raise the temperature of the premises.
You can throw out plants that blossom in spring and autumn. So, a daisy, an anemone, etc., planted in autumn or winter in a room, can blossom already in December. Blooming gladiolus can both speed up and delay. For their forcing out bulbs stored from November to mid-December at a temperature of 17 ° C, and then at a temperature of 20 ° C until the end of January and beginning of February.
For the delay of flowering, the bulbs are cooled in the cellar from January to the beginning of June( at a temperature of 2-4 ° C), so that in the soil they bloom for a month, and go and one and a half later than usual.
Light is the second most important factor( after the temperature) that can accelerate or slow flowering.
For many plants, a clear relationship between flowering and the length of daylight is established. Lighting plants of a long day in a period when the days are short, you can accelerate their flowering, and vice versa: reducing the light day to 8-10 hours contributes to the earlier blooming of plants of a short day.
Cleverly varying the temperature and light, you can achieve year-round cultivation of chrysanthemums, freesias, calanchoe, gladiolus, etc.
Scientists managed to get substances with which you can accelerate or slow the beginning of flowering. In recent years, such drugs have appeared on sale.
What are these substances?
Auxins are a group of substances( alpha-naphthylacetic, beta-indole and acetic acid, beta-indolyl-butyric acids), which increase the rooting, rooting, growth of plants, while inhibiting the laying of flower buds. Used auxins in the form of powders, more rarely - solutions.
Gibberellins( gibberellin A1, A2, A3, A4, etc., gibberellic acid) stimulate growth in height( due to lengthening of cells and partly due to their rapid division) and promote the removal of plants from the state of rest. Hyacinths and azaleas treated with substances of this group do not need to be cooled to leave the rest period.
Cytokines( benzyladenine, kinetin) are used to accelerate the germination of seeds that germinate usually very slowly and unfavorably. Cytokines increase the branching of plants and "wake up" the kidneys.
Substances that inhibit plant growth, -absiatic acid, etc. They increase the frost resistance of plants and their resistance to adverse weather conditions, increase the number of buds and flowers. These substances are used, for example, in the cultivation of greenhouse carnations( to reduce internodes and to obtain harder stems).7
Moisture and nutrient content of the soil can also affect the timing of flowering. All of the above factors must be interrelated. Only in this case it can be ensured that the forcing will be carried out.
It is necessary to remember the rule: accelerate the flowering dosage top dressing with nitrogen against the background of increasing potassium doses. Excessive application of nitrogen, as a rule, prolongs the period of vegetation and delays flowering.
There are techniques to stop blooming. As a rule, for this plant, less favorable conditions for development are created. If, for example, the optimum temperature for a given species is 16 ° C, then it is reduced to 10-12 ° C.In this case, the processes of vital activity in the plant slow down, and its flowering is delayed. You can manipulate and light: if, for example, to further illuminate chrysanthemums or poinsettia, then their growth will continue, and the bookmark of flower buds and flowering will slow down. And, on the contrary: to delay the flowering of plants of a long day, they should be darkened.
Not all ornamental plants are capable of forcing out, but bulbous plants are considered to be the best endangered plants.