The main methods for controlling flowering period include the following:
1. Temperature regulation: warming up: can timely prevent flowers from entering the dormant period, thereby advancing the flowering time. For example, flowers such as peonies and azaleas can choose warming methods to advance their flowering period. Heating can also cause most flowers to bloom earlier in winter. Cooling: It can reduce the metabolic rate of flowers and prolong the flowering period. For example, for flowers that are about to bloom or just beginning to bloom, they can be placed in a cold room at 2 ° C to 5 ° C to slow down plant metabolism and thus delay flowering.
2. Light regulation: including different methods such as adding light, blocking light, and reversing light and dark. Add light: To make long day flowers bloom in autumn and winter when natural sunlight is short, artificial light can be added for 3 to 4 hours after sunset, supplemented by appropriate heating. Shading: Using black shading for several hours during the day can delay the flowering period; Short day flowers such as chrysanthemums and poinsettias can bloom earlier if they are shaded for several hours in the evening or morning; On the contrary, if the light is artificially increased for several hours, flowering can be delayed. Reversal of light and dark: For flowers that have a habit of flowering at night, such as Epiphyllum, shading during the day and artificial lighting at night can make them bloom during the day after budding.
3. Cultivation measures: For certain annual flowers or bulbous flowers, the method of sowing or planting in stages can be used to make the flowering period earlier or later. Pruning, heart picking and other measures can also control the flowering period. If the remaining branches of roses and dahlias are frequently cut off, they can bloom again after the branches are renewed; Picking the heart before flowering can delay the flowering process.
4. Water and fertilizer regulation: Water: flowering timing can be controlled by adjusting the water supply time. Some flowers and trees have differentiated their flower buds at the turn of spring and summer. At this time, if drought conditions are caused by people, they will fall leaves or peel leaves early, and then spray water to supply water. They can often bloom for the second time that year. During the blooming period of flowers, watering can be reduced appropriately to make the soil in the pot dry, so that the flowering period can be extended appropriately. Fertilizer: In the early stage of flower growth, excessive application of nitrogen fertilizer can often delay flowering. After the plant reaches a certain level of nutritional growth, increasing the application of phosphorus and potassium fertilizers can promote early flowering. Applying nitrogen fertilizer once at the end of flowering can prolong the flowering period of herbaceous flowers that are gradually blooming; For flowers with a relatively short flowering period that cannot bloom continuously, fertilization should not be applied until the flower buds begin to show color and wither in order to extend the flowering period.
5. Hormonal regulation: Plant growth regulators are used to regulate the flowering of flowers. Commonly used growth regulators include gibberellin, ethephon, and dwarfism, among which gibberellin has a significant effect on promoting flowering.
There are various methods for controlling flowering period, which should be selected according to different plant species and varieties, while paying attention to the coordination of other corresponding measures and environmental conditions.