4 methods for regulating flowering periods to make flowers bloom on special days
To make flowers bloom at the right time according to people's needs, you must, on the basis of thoroughly understanding the growth and development patterns of various flowers, become familiar with the environmental requirements of different types of flowers at different stages of growth and development. The commonly used technical measures for regulating flowering periods by adjusting environmental conditions and the flowers' own growth and development processes include the following 4:
Regulatingfloweringperiods: Day-length treatment method
(1) Short-day treatment: This method can make short-day flowers bloom ahead of schedule, such as chrysanthemums, poinsettias, bougainvillea, and Christmas cacti. After these flowers have grown vigorously, shading treatment is used, commonly covering the whole plant tightly with black cloth (or black plastic), giving only 8-10 hours of light per day. After 50-60 days of this treatment, they can bloom ahead of schedule.
(2) Long-day treatment: Using long-day treatment can delay the flowering period of short-day plants. For example, if chrysanthemums are given supplemental light from lamps every day before flower bud differentiation (late August), so that the daily light exposure exceeds 12 hours, flower bud formation can be inhibited and flowering delayed; conversely, supplemental lighting can also be used to make long-day flowers bloom ahead of schedule.
Regulating flowering periods: Temperature treatment method
(1) Heating treatment: For flowers that need relatively high temperatures to form flower buds, such as Chinese roses, jasmine, Aglaia odorata, cineraria, gloxinia, periwinkle, and geraniums, as long as heating is started in advance, they can bloom as scheduled when needed. For flowers that are overwintering in dormancy but have already formed flower buds, such as plum blossoms, tree peonies, ornamental peaches, and winter jasmine, after they have endured frost and snow, move them indoors and gradually raise the temperature, keeping the room temperature at 5-25 degrees, and spray frequently, so they can bloom ahead of schedule.
(2) Low-temperature treatment: Mostly used for flowers overwintering in dormancy, such as rhododendrons, plum blossoms, and ornamental peaches. If you do not want them to bloom in spring, place them in a cold cellar at 2-5 degrees, water about once every half month, and the flowering period can be delayed until "May Day" or "National Day."
Regulating flowering periods: Chemical treatment method
Using plant growth regulators to treat flowers can break dormancy, promote flower bud differentiation, and make them bloom ahead of schedule. For example, treating hydrangeas, rhododendrons, and cherry blossoms with 200-400 mg/kg gibberellin is effective for breaking dormancy.
Regulating flowering periods: Cultivation measure method
Use cultivation measures such as sowing, cuttings, pruning, and pinching at different times to control the flowering period. For example, gladiolus can be planted in stages so that flowers are available in all four seasons; scarlet sage can have its flowering period delayed by more than 20 days by pinching; dahlias take about 120 days from cutting to flowering, and staged cutting propagation can regulate the flowering period. Below are two methods for regulating the flowering period using cultivation measures:
(1) Controlling sowing time: Plants need a certain amount of time to grow until flowering, and regulating the flowering period by controlling sowing time is a relatively good method. For example, if scarlet sage is sown indoors in winter and a certain temperature is maintained, it can bloom in spring. However, for some plants whose flowering is controlled by long or short day length, sowing earlier or later is often affected by day length, and the plant may bloom before it has grown to maturity. For example, with poinsettias, even if the plant is very small, it will bloom as long as it is given short days.
(2) Pruning: During the flower growing period, measures such as pinching and bud thinning can be used to control flower bud formation and delay the flowering period. For example, continuously pinching marigolds inhibits flower bud formation and can delay the flowering period. Cutting off the spent flowers of blooming marigolds and strengthening water and fertilizer management will promote new branches to grow and bloom, extending the flowering period. For some flowers that are not suitable for pinching, such as single-head cockscomb, the method of controlling sowing time can be used to achieve the goal.