Sunflower blooming season
Answering netizens' questions about the blooming season of sunflowers and sharing experience on green plant maintenance regarding sunflower flowering time, the specific content is as follows:
Sunflower is a large annual Asteraceae plant that can grow up to 3 meters tall, with bright and elegant flowers that are very suitable for ornamental decoration. Let's take a look at when sunflowers bloom and how long their flowering period lasts.
When do sunflowers bloom?
Under normal circumstances, sunflowers are sown from March to April and bloom from July to August. Sunflowers can bloom throughout the year, the secret is "accumulated temperature," which means that as long as plants accumulate a certain amount of temperature during growth, they can bloom. It usually takes 6 to 9 days for a sunflower flowerhead to bloom from the ligulate flowers to the tubular flowers, with the peak flowering period being from the second to the fifth day, accounting for about 75% of the total number of flowers. Most flowers open between 4 to 6 a.m., are pollinated and fertilized the next morning, and the unpollinated branches can remain wilt-free for 7 to 10 days.
Growth environment of sunflowers
1. Temperature: Sunflowers are warm-loving and cold-tolerant crops, with good adaptability to temperature. The seeds have a strong tolerance to low temperatures and start to germinate when the soil temperature is stable at 2℃ or above, can germinate and root at 4 to 5℃, and can meet the needs of seedling emergence when the soil temperature reaches 8 to 10℃. As long as the temperature does not drop below 10℃, sunflowers can grow normally throughout their growth process.
2. Water: Sunflowers are crops that consume a lot of water. With large plants and dense leaves, they absorb 1.74 times the amount of water as corn. However, due to their growth being synchronized with local rainfall and heat, the contradiction between water supply and demand is not prominent, and the water requirements at different growth stages vary greatly. From sowing to budding, not much water is needed. From budding to flowering is the peak water requirement period, and from flowering to maturity also requires a considerable amount of water.
3. Light: Sunflowers are short-day crops, but their response to daylight is not very sensitive. They enjoy plenty of sunlight, and their seedlings, leaves, and flowerheads have a strong phototropism. Sufficient daylight can prevent the seedlings from becoming leggy. Abundant sunlight during the middle growth stage can promote vigorous stem and leaf growth, normal flowering and pollination, and improve seed setting rate. Abundant sunlight during the later growth stage ensures that the seeds are full and plump.
4. Soil: Sunflowers have low soil requirements and can grow in various types of soil, from fertile soil to dry, infertile, and saline-alkali soil. They not only have a strong tolerance to salt and alkali but also have the ability to absorb salt. Additionally, sunflowers have a well-developed root system and are highly drought-resistant. Moreover, sunflowers have a well-developed aeration tissue in their roots and stems, making them very flood-tolerant.
Sunflowers are named for their flowers that often face the sun, and many people enjoy this type of flower. So when do sunflowers bloom and how long is their flowering period? Let's take a look together!
Growth cycle of sunflowers
1. Seedling stage: The period from emergence to budding is called the seedling stage, which usually takes 35 to 50 days, or 28 to 35 days for summer sowing. This period is the formation of leaves, floral primordia, and the differentiation of small flowers. The seedling stage of sunflowers is the stage with the strongest drought resistance, where the aboveground part grows slowly, and the underground root system grows rapidly, quickly forming a strong root system.
2. Budding stage: From budding to flowering, it usually takes about 20 days, which is a period of simultaneous vegetative and reproductive growth and the most vigorous stage of life. This period requires the most fertilizer and water, accounting for about 40 to 50% of the total requirement. If the needs for water and fertilizer are not met in time, it will seriously affect yield.
3. Flowering stage: It usually takes 6 to 9 days for a sunflower flowerhead to bloom from the ligulate flowers to the tubular flowers, with the peak flowering period being from the second to the fifth day, mostly opening between 4 to 6 a.m., and pollination the next morning. Unpollinated branches can remain for 7 to 10 days, but the self-pollination seed setting rate is only about 3%, while cross-pollination has a higher seed setting rate.
4. Maturation stage: The maturation stage of sunflowers refers to the period from flowering to maturity, which takes 25 to 55 days for spring sowing and 25 to 40 days for summer sowing, with some variation between different varieties. About 15 days after flowering and pollination is the seed formation stage. The maturation stage requires sunny weather, a large diurnal temperature difference, and suitable soil moisture.
This article shares the blooming season of sunflowers and detailed explanation of sunflower flowering time, hoping to provide help in green plant management!