The method of forcing peony flowers in a greenhouse during winter
If you want to know about the experience of forcing the woody flower peony, the method of forcing peony flowers in a greenhouse during winter, follow the editor to take a look together!
Greenhouse flower forcing, commonly known as fumigation of flowers, is a method of artificial heating in a greenhouse to make peonies sprout, grow, and bloom again in the cold winter of the north. The selection of varieties; the requirements for potting soil, and the method of potting are the same as those in the outdoor forcing in the south, except that some management methods and steps are also similar, but some technical requirements differ. The main management techniques are now introduced as follows:
I. Potting Time
In greenhouse flower forcing, as long as the method is correct, with suitable temperature, sunlight, and water, it generally takes about 45 days to meet its growth, development, and blooming needs, so the potting time should be determined according to the desired blooming time.
II. Initial Management
Peonies grow and bloom in the field from low to high temperatures in spring, which gradually rise to ensure good growth, large and full flowers, and bright colors. Therefore, flower forcing in the greenhouse should also follow its growth habits, master the temperature to make it gradually rise, and try to approach the conditions required for its natural growth. The temperature in the early stage is generally maintained at 10-14 degrees during the day and 6-8 degrees at night. After a week, the temperature can be increased to 14-16 degrees during the day and 10-12 degrees at night. Maintaining this, after about 10 days of potting, the flower buds can germinate and become fat and glossy, and after about 15 days, the buds can be seen; the frequency of watering depends on the small evaporation inside the greenhouse and the high relative humidity, with light watering 1-2 times a day being enough to meet the plant's water needs.
III. Intermediate Management
After the peony shows buds, it enters the normal growth and development stage. The temperature during the day can be raised to 16-18 degrees, and at night to 12-14 degrees. After about 20 days, it enters the young bud stage. The buds during this period are more tender and sensitive to sudden changes in temperature than those forced outdoors in the south. Often, due to the poor resistance of young buds, they can abort. Therefore, it is best to keep the temperature in the greenhouse relatively stable.
After 28 days, the plant enters the leaf expansion stage. The temperature during the day can be raised to 18-20 degrees, and at night to 14-16 degrees. In the morning, when the temperature does not suddenly drop, a small part of the skylight at the top of the greenhouse can be opened for ventilation to exercise the plant's resistance. If the temperature exceeds 25 degrees, the skylight can be opened wider to gradually lower the temperature. It is forbidden to open the windows at the bottom of the greenhouse for ventilation to cool down, as this may cause the air to directly strike the plants, stopping the development of the buds, commonly known as a cold. Even if the temperature is increased later, it will not develop, reducing the survival rate. During this period, in addition to light watering twice a day, it is also necessary to water thoroughly every 2-3 days depending on the dryness of the potting soil, and foliar fertilizers can also be sprayed.
35 days later, the flower buds enter the flat bud stage. The resistance of the buds to adversity is enhanced, and as long as the temperature changes are not too large, the effect on the flowering rate is not significant. Therefore, during this period, the temperature inside the greenhouse should be adjusted flexibly according to the planned blooming time. The temperature during the day should be maintained at 20-22 degrees, and at night at 16-18 degrees. In addition, the relative humidity inside the greenhouse is high, often causing stem rot disease. Before the onset of the disease, a 50% wettable powder of benomyl or a 10% wettable powder of thiabendazole can be sprayed preventatively in combination with foliar fertilization.
IV. Late Management
After 42 days, the flower buds enter the opening stage and can bloom in 2-3 days. Therefore, at this time, the plants can be moved out of the greenhouse according to the number of flowers (pots) needed and the time when they need to bloom. Plants that are not needed temporarily can be stored in a cool room at 2-4 degrees. After being placed for 10-20 days, they can still bloom normally. For some late-blooming plants, additional heating can be applied to promote blooming.
V. Light Regulation
Peonies are long-day plants. Flower buds form in long-day conditions and bloom under medium-long-day conditions. Insufficient light during the initial stage of flower forcing can result in leaf growth without bud formation, and insufficient light in the later stage can affect the quality and blooming time of the flowers. Therefore, when there is a lot of cloudy weather and insufficient light, artificial light sources should be supplemented. The practice in Luoyang is to use a 500-watt bulb to add light from dusk. Before the buds appear, add light for 3 hours, with an average daily light intensity of 4045 lux; during the bud expansion stage, add light for 5 hours, with an average daily light intensity of 5150 lux; during the leaf expansion to blooming stage, add light for 7 hours, with an average daily light intensity of 5330 lux, which can advance blooming by 3-4 days, with green and large leaves and better flower development.
The above is the complete introduction to the method of forcing peony flowers in a greenhouse during winter. I hope it can be of help to you. Don't forget to check out more flower cultivation experience and knowledge!