When does petunias bloom?
As a common ornamental flower in the courtyard, petunias are favored by gardening enthusiasts for their rich colors and long flowering period. However, many novice flower lovers are often confused by its specific flowering period. This article will comprehensively analyze the flowering mystery of petunia from natural laws to artificial control. Natural flowering characteristics of petunias are regular in four seasons. Under natural growth conditions, the flowering period of petunias usually starts in late spring and April, and the full flowering period can last until the frost season in October. Its single flower opens for about 5-7 days, but the whole plant can continue to bloom through reasonable maintenance and management. Differences in climatic zones show that due to the low accumulated temperature in the northern region, the peak flowering period is concentrated from June to September; in the southern warm region, flowering can be advanced to mid-March. When the temperature difference between day and night is maintained at 10-15℃, the colors are the most vivid and saturated. The precise control of water and fertilizer in the flowering period extension maintenance system adopts the watering principle of "seeing dry, seeing wet", and maintains the substrate humidity of 40%-60%. Phosphorus and potassium fertilizers (N-P-K=5-15-30) are applied every 10 days during the bud pregnancy period, and the EC value is best controlled at 1.2-1.8mS/cm. Light and temperature management ensures 6 hours of direct light every day, and proper shade during high temperatures in summer. The flowering efficiency is the highest when the night temperature is not lower than 12℃ and the day temperature is not higher than 28℃. In what season, petunia was picked 2-3 times during the flowering plant morphology control seedling stage, and topped for the first time when the main stem was 10cm. Cut off the residual flowers in time after flowering to the second pair of leaves, and apply brassinolide to stimulate lateral bud differentiation. Flower-inducing techniques in special seasons In winter greenhouse cultivation, LED fill light (light intensity 8000-10000lux) is needed, and hibernation can be broken with 50ppm gibberellin treatment. Spraying 0.1% ferrous sulfate solution during high temperature periods in summer can prevent yellowing and falling leaves.
Through a systematic maintenance plan, petunia can not only achieve annual flowering, but also cultivate special ornamental effects such as two-color gradient through color control technology, creating a continuously stunning visual focus for the courtyard landscape.