When is the best time to plant sunflowers
Today, the editor will explain the best time to plant sunflowers and share some experience on the maintenance of ornamental sunflower planting time and methods. It's a great piece of knowledge, so it's recommended to save it for later!
Sunflowers are cold-tolerant crops. In the northern part of China, they can be sown in late March, or even in autumn. However, in recent years, the incidence of diseases in sunflowers has been increasing year by year, coupled with poor pollination and low seed setting rate. Research has shown that early sowing in the northwestern part of Jilin Province has become one of the important factors restricting sunflower yield, and timely late sowing is an important measure to increase production.
For conventional sunflower varieties, the sowing period is from May 10th to 20th, for hybrid sunflower varieties, the sowing period is from May 25th to June 10th. For oilseed sunflower hybrids, the sowing period is from May 30th to June 20th. Different varieties have different requirements for sowing time, and the actual sowing time should be determined according to the seed instructions.
Growth period = the number of days from the sowing date to the average first frost date in the area + 7 days. Using this formula, it is easy to determine the sowing period.
Increase seedling survival rate. Late sowing ensures that the seedlings emerge after the strong wind period has passed, reducing the impact of sand. At this time, all kinds of plants have germinated, and there are more food sources for seedling pests, which can reduce the damage caused by pests.
Conducive to growth and development. Sowing in mid-to-late April makes the sunflower from seedling stage to budding stage in a dry and low-temperature period, inhibiting growth and reducing the number of small flowers.
Increase seed setting rate. Late sowing results in flowering period in early August, which is about 15 days later than early sowing fields. At this time, the consecutive rainy weather is significantly reduced, which is conducive to insect pollination.
Reduce the occurrence of diseases. Sunflowers have strong resistance to diseases before flowering, but their resistance weakens significantly after flowering. Late sowing avoids the high temperature and peak rainfall in mid-to-late July.
Increase the weight of 100 seeds and increase the kernel rate. Timely late sowing reduces leaf spot disease, which is conducive to filling and results in plump seeds.
Conducive to field management. Late sowing ensures that field weeds have already germinated by the time of sowing, and a large number of field weeds are eliminated with the sowing operation.
Preparations before sowing include: Sunning seeds: One week before sowing, choose a sunny day to spread the seeds on a dry, sunny ground or plastic sheet, and continuously sun the seeds from 10 am to 4 pm for 1-2 days, which can reduce moisture content, promote seed activity, enhance viability, and improve germination potential and rate.
Seed soaking: In saline-alkali soil, seeds absorb soil moisture slowly, germinate late, and emerge late, which increases the risk of damage from salt and alkali. Soaking or germinating seeds before sowing can reduce the amount of water absorbed by seeds in the soil and shorten the germination time, significantly improving the emergence rate. The specific method is to use clear water at about 25°C or a boric acid solution of 0.1%-0.5% at room temperature of 18-20°C, soak oilseed varieties for 8-10 hours, and food varieties for 10-12 hours. After soaking, remove the seeds from the shade and dry them before sowing.
The above is all about the best time to plant sunflowers and the planting time and methods of ornamental sunflowers. Have green plant enthusiasts understood it?