Flowering period regulation technology of flowers

The technology of regulating the flowering period is also called the technology of delaying the flowering period. There have been flowering period regulation technologies since ancient times, and there are records of "flowers blooming at any time".
1. Ways to regulate the flowering period
   People use various cultivation techniques to make flowers bloom at regular times according to people's wishes outside the natural flowering period, which is the so-called "promoting hundreds of flowers in a moment and gathering four seasons in one time". Those whose flowering period is earlier than the natural flowering period are called forcing cultivation, and those whose flowering period is delayed than the natural flowering period are called inhibiting cultivation. The main ways to regulate the flowering period are:
1. Temperature treatment: The effects of temperature are mainly in the following aspects:

① Breaking dormancy: increasing the activity of dormant embryos or growth points, breaking the spontaneous dormancy of vegetative buds, and making them germinate and grow.

② Spring flower effect: At a certain stage of the life cycle of flowers, under certain low temperature conditions, after a certain period of time, the spring flower stage can be completed, so that flower bud differentiation can be carried out.
③ Flower bud differentiation: Flower bud differentiation requires a certain temperature range. Only within this temperature range can flower bud differentiation proceed smoothly. The suitable temperature for different flowers is different.
④ Flower bud development: After the flower bud differentiation of some flowers is completed, the flower buds enter a dormant state. It is necessary to carry out necessary temperature treatment to break the dormancy and bloom. Flower bud differentiation and flower bud development require different temperature conditions.
⑤ Influence on the elongation of flower stems: The flower stems of some flowers need a certain low temperature treatment before they can elongate and grow at a higher temperature, such as hyacinth, tulip, Clivia, trumpet daffodil, etc. There are also some flowers that require low temperature for the spring flower effect, which is also necessary for the elongation of flower stems, such as freesia, bulbous iris, musk lily, etc.
   It can be seen that temperature plays a decisive role in breaking dormancy, spring flower effect, flower bud differentiation, flower bud development, and flower stem elongation. Therefore, by taking appropriate temperature treatment, dormancy can be broken in advance, flower buds can be formed, and flower bud development can be accelerated to bloom early. Otherwise, flowering can be delayed.
    Light treatment: For long-day flowers and short-day flowers, the sunshine time can be artificially controlled to bloom early, or delay flower bud differentiation or flower bud development, and adjust the flowering period.
3. Chemical treatment: It is mainly used to break the dormancy of bulbous flowers and flowers and trees, and bloom early. Commonly used chemicals are mainly gibberellins (GA) chemicals.
4. Cultivation measures treatment: By adjusting the propagation period or planting period, pruning, pinching, fertilizing and controlling water can be used to effectively adjust the flowering period.
2. Methods for regulating the flowering period The flowering
period can be adjusted through the above four main ways of promoting and inhibiting cultivation of flowers to ensure the smooth progress of regulating the flowering period.
1. Preparation before treatment.
1. Selection of flower types and varieties:
According to the time of using flowers, first choose the appropriate flower types and varieties. On the one hand, the flowers selected should fully meet the needs of the market. On the other hand, the flowers that are easy to bloom during the blooming period and do not require too much complicated treatment should be selected to save time and reduce costs. Different varieties of the same flower react differently to treatment, and the difference is even great. For example, the early-flowering variety "Nanyang Dabai" of chrysanthemum blooms after 50 days of short-day treatment, while the late-flowering variety "Fo Jian Xiao" needs to be treated for 65 to 70 days before it can bloom. In order to bloom early, early-flowering varieties should be selected. If you want to delay flowering, you should choose late-flowering varieties.

2. Maturity of bulbs:
To promote cultivation of bulbous flowers, it is necessary to promote the early maturity of bulbs. The maturity of bulbs has a great influence on the effect of forced cultivation. Bulbs with low maturity have poor results. The quality of flowering is reduced, and even the bulbs cannot germinate and take root.
3. Plant or bulb size:
Choose plants or bulbs that are strong and can bloom. According to the requirements of commodity quality, plants and bulbs must reach a certain size, and the quality of flowers can be guaranteed after treatment. If plants that have not grown fully are used for treatment, the quality of flowers will be reduced and cannot meet the needs of flower applications. Some perennial flowers need to reach a certain age before they can bloom. When processing, plants that have reached the flowering age should be selected for treatment. For example, the bulbs of tulips must reach more than 12 grams and the diameter of hyacinth bulbs must reach more than 8cm before they can bloom.

4. Treatment equipment and cultivation technology: There must be perfect treatment equipment such as temperature control equipment, supplementary light equipment and light control equipment. Fine cultivation management is also very necessary.
㈡ Temperature treatment:
1. The temperature treatment of flowers should pay attention to the following issues:
① Different varieties of the same flower also have different temperature sensitivity;
② The high and low treatment temperatures are mostly different depending on the climatic conditions of the origin or breeding place of the variety. Temperature treatment generally takes 20℃ or above as high temperature, 15~20℃ as medium temperature, and 10℃ or below as low temperature;
③ The treatment temperature also varies depending on the climatic conditions of the cultivation site, the harvest period, the length of time from listing, the size of the bulbs, etc.
④ The appropriate period of temperature treatment, such as treatment during the growth period or during the dormant period, varies depending on the type and variety characteristics of the flowers.
⑤ The effect of temperature treatment varies depending on the type of flowers and the number of days of treatment.
⑥ The flowering period control of multiple flowers requires the comprehensive treatment of temperature and light at the same time, or the use of several treatment measures in the process of treatment to achieve the expected effect.
⑦ Cultivation management during or after treatment has a great influence on the effect of controlling the flowering period.
2. Temperature treatment during dormancy:
⑴ Tulip (Tulipa gesneriana): In June, the temperature gradually rises, and the aboveground part of the tulip gradually turns yellow. When more than 1/3 of the leaves turn yellow, it is the right time to harvest. After harvesting, the bulbs should be dried slowly and naturally. The temperature should not exceed 35 ℃. Generally, they are dried at 35 ℃ for 3 days; dried at 30 ℃ for 15 days, and then treated at 20 ℃ and 60% relative humidity to promote flower bud differentiation. 20 ℃ is the appropriate temperature for tulip flower bud differentiation. It is treated for about 20 to 25 days, and then 8 ℃ for 50 to 60 days to promote flower bud development; then 10 to 15 ℃ for rooting treatment, and it can be planted when the roots are pulled out. It is also possible to avoid high-temperature drying treatment. In an airy place at 20°C, the flower buds are differentiated while drying. From the stage of external stamen formation, the flower buds are treated at 8°C for a long time to promote the development of flower buds. When the root crown appears, the roots are promoted at 15°C, and then they can bloom in 60 days at 15-20°C. This method has slow flower bud development, early root activity, and good flowering. Early-flowering varieties of the Darwin system are often used in the forcing cultivation of tulips.
⑵ Gladiolus (Gladiolus hybrida): Generally, it is placed in a cold storage at 3-5°C in mid-March to inhibit the germination and rooting of the bulbs. It can be taken out and planted for a certain period of time according to the time of use of flowers. Usually, early-flowering varieties can bloom about 75 days after planting.
⑶ Musk lily (Lilium longflora): When used for cut flower production, the bulbs are stored in refrigerated equipment, and planted in batches, which can provide flowers all year round. The temperature treatment of black-shafted lily is to place it in a cold room for dormancy after harvesting, and to carry out rooting treatment at 15 ℃ in early September. It will start to root after 2 to 3 weeks, and then be placed at a low temperature of 0 to 3 ℃ for spring flower treatment for 45 days before planting, which can bloom early.
The temperature treatment of lily bulbs should pay attention to the bulbs used for forcing cultivation. Before the rooting treatment, a period of high temperature after-ripening treatment should be carried out at a temperature of 30 ℃. The bulbs need to be refrigerated after the rooting treatment. If the rooting treatment is not carried out and the refrigeration treatment is carried out directly, some of the bulbs will not take root, and the number can reach about 50%. In addition, lilies are skinless bulbs and are not resistant to dryness. During the storage of the bulbs, the appropriate humidity must be maintained at all times. Generally, the bulbs are placed in boxes, and the gaps are moisturized with damp sphagnum moss.

⑷ Freesia (Frisia refracta): Select early-flowering varieties for forced cultivation. After the bulbs are harvested and dried, they are stored. When treated with temperature, they are treated at 30°C for 40 to 60 days to break dormancy, and then treated at 10°C for 30 to 35 days. The humidity is maintained at about 90% to meet the temperature requirements of spring flowering, flower bud differentiation, and flower stem elongation. Then plant them. The cultivation temperature is preferably 15 to 20°C. If the temperature after planting is higher than 20°C, the spring flowering effect will be eliminated, the flower bud differentiation will be poor, and deformed flowers will appear, which will greatly reduce the quality of the flowers.

⑸ Lily of the valley (Convalaria majalis): At the end of October, treat at 0.5 ℃ for 3 weeks, then cultivate at 23 ℃, and bloom in mid-December. It takes about 50 days from treatment to flowering. If the pillars are placed in a 0 ℃ cold storage for 50 days in mid-September, the effect will be better, and the flowers will be luxuriant and neat.
3. Temperature treatment during the growth period:
Low temperature treatment is carried out immediately after the seeds germinate. There are few flowers with vernalization effect, only cornflower (Centaurea cyanus), delphinium (Consolida ajacis), multi-leaf lupine (Lupainuspolyphyllus), etc. When the plant's vegetative growth reaches a certain level, low temperature treatment can promote flower bud differentiation in many types of flowers, such as Matthiola incana, Primulamalacoides, Senecio cruentus, Freesia refracta, Dendrobium spp., Agyranthemum frutescens, etc. In places with high temperatures in summer and autumn, the stems of these flowers do not elongate and the leaves are in a rosette shape. During this period, low temperature treatment will form flower buds and the stems will also grow vigorously. In traditional flower production, the method of adjusting the sowing period is often used, such as using natural low temperatures or temperature differences in the cultivation site for off-site cultivation. This can greatly save management costs, reduce costs, and facilitate mass production.
⑴ Violet: There are also some differences in the temperature sensitivity of violet varieties. Winter flower types, intermediate types and other cut flower varieties should be treated with temperature when the true leaves are about 10: ① Violet flower bud differentiation or vernalization treatment, can only bloom when the daytime temperature is below 15.6 ℃, and it cannot bloom at any time when it is above 18.3 ℃; ② At temperatures above 15.6 ℃, the extended growth of the plant is inhibited; ③ Temperature treatment above 15.6 ℃ will cause morphological changes in the leaves of the plant, such as serrated or wavy deformities on the leaf edges. In the regulation of the flowering period of violets, it should be noted that it is not easy to resume growth after transplanting large seedlings. It is advisable to transplant when there are 2 to 5 true leaves, and try to minimize root damage. ⑵ Freesia: Rooting is promoted at 15-18℃. When the leaves are 5-6 and the plant height is 25cm, low temperature treatment of 10-13℃ is given to promote flower bud differentiation and create conditions for flower stem elongation. Then, it is placed in a greenhouse to promote flower bud development and flowering. It can also be cultivated in a different place. First, rooting, growth, flower bud differentiation and conditions for stem elongation are created in a cold place, and then it is moved to a warm place or greenhouse to promote flower bud development and flowering.
⑶ Primula: At a low temperature of 10℃, flower bud differentiation can be carried out in long-day or short-day conditions. If short-day treatment is carried out at the same time, flower bud differentiation is better. After flower bud differentiation, the temperature is maintained at about 15℃, and long-day treatment is carried out to promote flower bud development and early flowering. Primula obconica has similar habits, but not as obvious as Primula obconica. ⑷ Peony (Paeonia lactiflra): Usually natural low temperature treatment is used. It enters the greenhouse after December and blooms after February. It can also be treated with low temperature of 0 to 2°C in early September, 25 to 30 days for early flowering varieties, 40 to 50 days for late flowering varieties, and then treated at 15°C for 60 to 70 days to bloom.

⑸ Chrysanthemum (Dendranthema morifolium): Under short-day conditions and no low temperature, the leaves grow in a rosette shape, and the stems do not elongate. Dormancy can be broken by treating at 0 ℃ for 30 days and below 5 ℃ for 21 days. It can also be broken by treating with gibberellin (GA). The temperature required for flower bud differentiation varies depending on the variety. Temperature-insensitive varieties can differentiate flower buds at 10 to 27 ℃, and 15 ℃ is the optimal temperature for flower bud differentiation. High-temperature varieties inhibit flower bud differentiation under low temperature conditions, and the optimal temperature for flower bud differentiation is above 15 ℃. Low-temperature varieties inhibit flower bud differentiation under high temperatures, and below 15 ℃ is the optimal temperature for flower bud differentiation.
4. Management after temperature treatment:
⑴ Preparation before planting: Soil disinfection should be carried out about one month before planting. If fertilizer is insufficient, fertilizer should be applied. If planting in the ground bed, it is necessary to turn the soil about 30cm deep, add coarse-grained soil to the lower layer, add loose, fertile and well-drained soil to the upper layer, and apply appropriate amounts of decomposed cake fertilizer, superphosphate, plant ash and other quick-acting fertilizers. If planting in boxes, the box soil used should be more fertile than the soil for bed planting. It should be fully irrigated and shaded 2 to 3 days before planting to prevent the ground temperature from rising and maintain a cool environment.
⑵ Planting method: The rooting part of daffodils, tulips, hyacinths, etc. is at the base of the bulb. When planting, it should be level with the soil surface. The bulb of tulip can be exposed to about 1/3 of the soil surface. In this way, it will bloom early under the influence of warm temperatures, but the growth of the bulb is poor, and it is easy to differentiate into several small bulbs, and it will not bloom the next year. The planting depth of freesia and lily should be deeper, and fertile soil should be added after germination. For example, when planting freesia, cover the bulb with soil about 1cm, and cover it with soil 2.5cm when there are 3 to 4 true leaves. This can promote the growth and development of the plant. As long as the water is controlled and not watered too much, the plant can be placed in a pot and germinate neatly. The large bulbs of lily can be potted. The bulbs of musk lily with a circumference of 15cm can be placed in an 18cm flower pot, and 3 can be planted in each pot; the bulbs with a circumference of 18cm can be planted in each pot. When the bulbs or plants are taken out of the cold storage, they should not be planted immediately due to the high temperature. They should be placed in a cool environment of 15 to 17℃ for 1 to 2 days to give them adaptive training, and then planted. It is safer to plant on cloudy days, rainy days, or at night.

⑶ Management after planting: After planting, water should be fully irrigated. For bulbs that have begun to take root, holes should be dug on a fully leveled, unpressed bed surface for cultivation. Water should be irrigated after covering the soil. Avoid direct sunlight on the bed surface. High temperature and humidity often harm the root system, which is also one of the reasons for the rooting of tulips, bulbous irises, etc. Therefore, a shade shed should be set up on the planting bed, and grass on the ground can also prevent the temperature from rising. When planting in pots or boxes, they can be placed in the shade under buildings or trees, or in trenches. If the roots and germination are accelerated at low temperatures in the cellar, and then transplanted to a sunny place for cultivation after germination, the effect will be better. Lilies should maintain a temperature above 15 ℃, especially early-flowering musk lilies. Long daylight and high temperature promote flower bud differentiation. It is suitable to place them in a sunny place when the seedlings are 3 to 5 cm tall. The low temperature of 10 to 15 ℃ for freesia can promote flower bud differentiation. If the number of leaves before treatment does not reach 6 to 7 or more, the plants will bloom when they are short after treatment. The cultivation temperature of daffodils and tulips should not be lower than 10 ℃. Plants with dormant flower buds should be cultivated at 16-17 ℃ at night and not more than 20 ℃ at noon.
㈢ Light treatment: Long-day flowers can bloom early by supplementing light with artificial light in the short-day season. Long-term short-day treatment will inhibit flowering. Short-day flowers can promote flowering by shading in the long-day season. On the contrary, long-term long-day treatment will inhibit flowering. Most flowers that bloom in spring are long-day flowers, and most flowers that bloom in autumn are short-day flowers. Generally, for short-day flowers and long-day flowers, a light intensity of 30-50Lux has a sunshine effect, and 100Lux has a full sunshine effect. Usually, the sunshine intensity at noon on a sunny day in summer is about 100,000 Lux, which
can meet the light intensity requirements. Red light is the most effective artificial light source, with a wavelength of 6300 to 6600 (10-18m) having the strongest effect, followed by blue-violet light, of which 4800 (with the smallest effect, gradually increasing with shorter wavelength, and 4000) has the greatest effect. Flowers suitable for short-day treatment include chrysanthemums and poinsettias. Generally, poinsettias are shaded in summer. After mid-September, the sunshine hours are preferably 9 to 10 hours. When the sunshine hours are 11 hours, green spots can be seen on the bracts. The limit sunshine hours are 12 to 12.5 hours. Single-petal poinsettias can bloom in more than 40 days, while double-petal poinsettias take a little longer to process. The temperature should be above 15 ℃ during the process, and sufficient sunlight and good ventilation are required. If the temperature is lower than 15 ℃, the growth and development will be poor, the bracts and leaves will be poorly developed, and the quality will decline.
In order to make poinsettias bloom in "November" To bloom on National Day, 8 to 9 hours of light can be given every day at the end of July. Buds will form after one month and gradually open in late September.
㈣ Combination of light and temperature treatment:
In the regulation of the flowering period of flowers, sometimes a certain factor of light and temperature plays a significant dominant role in breaking dormancy, growth, flowering, flower bud differentiation, flower bud development, and flowering. For example, the flower bud differentiation period of violets requires low temperature treatment below 15 ℃, the flower bud differentiation of autumn chrysanthemums requires short-day conditions, and the dormancy breaking of lily of the valley requires low temperature treatment of 0 ℃, etc. However, two treatment factors are mainly used to make a reasonable combination to promote or delay flowering. For example, autumn chrysanthemums require flower bud differentiation under short-day conditions, but must be given a temperature above 15 ℃. If it is lower than 15 ℃, the flower bud differentiation will be blocked. At the same time
, the change of one treatment factor will cause other factors to change accordingly to achieve the desired effect. For example, primroses are treated with short-day light to promote flower bud differentiation. Only when the temperature is between 16 and 21 ℃. When the temperature drops to 10 ℃, flower buds can differentiate regardless of long or short daylight. When the temperature rises to 30 ℃, flower buds will not differentiate regardless of the length of daylight. Another example is the fairy finger (Schlumbergerarussalliana), which is a succulent plant and also a short-day flower. It requires 17 to 18 ℃ to bloom in short-day treatment. When the temperature reaches 21 to 24 ℃, it will not bloom even in short days. When the temperature drops to around 12 ℃, it can bloom in long days.
㈤ Cultivation technology treatment:
1. Adjust the propagation period and planting period:
① Adjust the sowing period: If the following flowers are listed on the "October" National Day, the sowing period is as follows:

If the sage is to be put on the market on May 1st, it can be sown in late August and cultivated in a greenhouse in winter. The tops should be pinched continuously to prevent flowering. The pinching should be stopped 25 to 30 days before May 1st. The calendula can be sown in September and cultivated in a low-temperature greenhouse in winter. It will bloom from December to January of the following year.
② Adjust the cutting period: If it is necessary to bloom on November 1st, you can plant leek in late March, plant lotus (red thousand leaves) in early May; plant tuberose and gladiolus in mid-July; plant canna on July 25th (potting, cutting off old leaves, protecting leaves and young shoots).
2. Other cultivation techniques:
① Pruning: To prepare for the market on November 1st, the late-flowering varieties of early chrysanthemums should be pruned from July 1st to 5th, and the early-flowering varieties should be pruned from July 15th to 20th. After the chrysanthemums are potted in March, they should be pruned 2 to 3 times, with the last pruning being done 20 days before the National Day.

② Pinching: Pinching the tops of the red sage 25 to 30 days before the National Day.
③ Leaf picking: Prunus mume should have its leaves removed from September 8 to 10, and it will bloom from the end of September to early October.
④ Fertilization: Appropriate application of phosphorus and potassium fertilizers and control of nitrogen fertilizers often promotes the development of flower buds.
⑤ Water control: Artificially control the water content to make the plant shed its leaves and go dormant. Then, when water is supplied at the appropriate time, it can be released from dormancy and sprout, grow, and bloom. This method can be used to make woody flowers such as peony, magnolia, and lilac bloom on New Year's Day or the Spring Festival.
In the process of controlling the flowering period, comprehensive technical measures are often used to control the flowering period, and the effect of controlling the flowering period is more significant.