When to Plant Sunflowers? A Full Breakdown of the Best Sowing Time
Sunflowers have a short growing cycle and are not afraid of high temperatures. To get good blooms, we generally choose to sow from March to April, which is the golden time for planting sunflowers. The best temperature for sowing sunflowers is between 18 and 25 degrees, and they will bloom about 50 to 80 days after planting.
Sunflowers could clearly get by on looks alone, yet they insist on relying on substance, and everyone surely loves them dearly. In fact, growing sunflowers is very simple, and beginners can easily grow them at home.
When to sow sunflowers? An introduction to sunflower sowing times
Sunflowers can be planted in all four seasons, usually with summer and winter as the main seasons, and the blooming period can last more than two weeks. Besides their sun-like appearance, their bright and generous flowers are very suitable for ornamental display, and the seeds have even greater economic value: they can be made into the much-loved sunflower seeds, and can also be pressed into low-cholesterol, premium edible sunflower oil. Let us take a look below at when to sow sunflowers!
Sunflower sowing time
The sowing time for sunflowers is March to April, the suitable temperature for sowing is 18 to 25°C, and they sprout about 5 to 7 days after sowing. The basic principle for choosing the sowing period is to sow appropriately early or late according to the patterns of salinization, so that the seedlings avoid salt and alkali damage. Spring or summer sowing is carried out according to the growth period of the variety. Adjust the sowing period according to the patterns of disease occurrence, so that it avoids the season when diseases are frequent. Adjust the sowing period according to growth characteristics, so that the flowering and grain-filling period avoids high temperatures above 28°C. The sowing method is dibbling, with about 1 cm of soil covering the seeds, and flowers appear about 50 to 80 days after sowing, with slight differences in each aspect depending on the variety.
The growing environment of sunflowers
1. Temperature: Sunflowers are a crop that likes warmth and tolerates cold, with strong adaptability to temperature. The seeds have very strong low-temperature tolerance: once the soil temperature is stable above 2°C, the seeds begin to stir, at 4 to 5°C they can germinate and take root, and when the soil temperature reaches 8 to 10°C it can meet the needs of seed germination and emergence. Throughout the entire growth process, sunflowers can grow normally as long as the temperature is not below 10°C.
2. Water: Sunflowers are a crop that consumes a lot of water, with tall plants and many dense leaves, and their water uptake is 1.74 times that of corn. However, because their growth and development mostly coincide with local rain and heat, the contradiction between water supply and demand is not prominent, and the water requirements differ greatly at different growth stages. From sowing to budding, they need little water; from budding to flowering is the peak water-demand period; and from flowering to maturity, the water requirement is also relatively high.
3. Light: Sunflowers are a short-day crop and are not very sensitive to day length. They like ample sunlight, and their seedlings, leaves and flower discs all have strong phototropism. With ample sunlight, the seedlings are robust and can be prevented from growing leggy. Ample sunlight in the mid-growth period can promote vigorous stem and leaf growth, normal flowering and pollination, and a higher seed-setting rate. Ample sunlight in the late growth period makes the seeds plump and full.
4. Soil: Sunflowers have low soil requirements and can grow in all kinds of soil, from fertile soil to dry land, poor soil and saline-alkali land. They not only have strong salt-alkali tolerance but also have salt-absorbing properties. At the same time, sunflowers have well-developed root systems and strong drought resistance. Moreover, the roots and stems of sunflowers have well-developed aeration tissue, making them very tolerant of waterlogging.
The growth cycle of sunflowers
1. Seedling stage: From emergence to budding is called the seedling stage for sunflowers, generally requiring 35 to 50 days, or 28 to 35 days for summer sowing. This period is the stage when leaves and flower primordia form and the florets differentiate. The seedling stage is the stage when sunflowers have the strongest drought resistance; the aboveground part grows slowly while the underground root system grows quickly, soon forming a strong root system.
2. Budding stage: From budding to flowering, sunflowers generally need about 20 days. This is a period when vegetative growth and reproductive growth proceed together, and it is also the most vigorous stage of their life. This period has the greatest demand for fertilizer and water, accounting for about 40 to 50% of the total fertilizer and water demand. If the need for water and fertilizer cannot be met in time, the yield will be seriously affected.
3. Flowering stage: For a single flower disc of a sunflower, from the opening of the ray florets to the completion of the opening of the tubular florets generally takes 6 to 9 days. From the second to the fifth day is the full-bloom period. The flowers mostly open between 4 and 6 in the morning, and are pollinated the next morning. Unpollinated stigmas can remain viable for 7 to 10 days, but the seed-setting rate from self-pollination is only about 3%, while the seed-setting rate from cross-pollination is high.
4. Maturity stage: The maturity stage of sunflowers refers to the stage from flowering to maturity, 25 to 55 days for spring sowing and 25 to 40 days for summer sowing, with differences among varieties. About 15 days after flowering and pollination is the seed formation stage. The maturity stage of sunflowers requires clear weather, a relatively large day-night temperature difference, and suitable soil moisture.
When is the best time to plant sunflowers? The planting time and methods for sunflowers
Speaking of sunflowers, everyone is surely familiar with them. Sunflowers are an annual herbaceous plant of the genus Helianthus in the Asteraceae family. They not only have high ornamental value but are also an important oil crop in our country, with high planting value, and have attracted many farmers to grow them. So, when is the best time to plant sunflowers? How should they be planted? Below, we will introduce the planting time and methods for sunflowers, so take a look.
Image: Sunflower
I. Sunflower planting time
The sowing time for sunflowers is March to April, the suitable temperature for sowing is 18 to 25°C, and they sprout about 5 to 7 days after sowing. The basic principle for choosing the sowing period is to sow appropriately early or late according to the patterns of salinization, so that the seedlings avoid salt and alkali damage. Spring or summer sowing is carried out according to the growth period of the variety. Adjust the sowing period according to the patterns of disease occurrence, so that it avoids the season when diseases are frequent. Adjust the sowing period according to growth characteristics, so that the flowering and grain-filling period avoids high temperatures above 28°C. The sowing method is dibbling, with about 1 cm of soil covering the seeds, and flowers appear about 50 to 80 days after sowing, with slight differences in each aspect depending on the variety.
Image: Sunflower
II. Sunflower planting methods
1. Land selection and preparation:For sunflower cultivation, choose a plot with level land, medium fertility, convenient irrigation and drainage, and relatively low soil clay content, and it should not be planted in continuous cropping. They reproduce by seed, and peat soil is suitable for sowing. Before sowing, mix the seeds with XIN GAO ZHI MO (a new high-fat film), which can repel underground pests, isolate viral infection, and increase the seed germination rate.
2. Timely sowing:The sowing time for sunflowers is generally March to April, the suitable temperature for sowing is 18 to 25°C, and they usually sprout about 5 to 7 days after sowing. The basic principle for choosing the sowing period is to sow appropriately early or late according to the patterns of salinization, so that the seedlings avoid salt and alkali damage. Spring or summer sowing is carried out according to the growth period of the variety.
3. Checking the field and filling in missing seedlings:Sunflowers are a dicotyledonous crop, and pushing through the soil to emerge is rather laborious. In addition, poor land preparation or sowing quality, surface soil crusting after rain following sowing, or damage from diseases, insects, rodents and birds can all easily cause missing seedlings and gaps in the rows. To ensure full emergence after sowing, you must check field by field and row by row during the emergence period, and replant in time where seedlings are missing in patches or rows.
4. Thinning and final singling of seedlings:In sunflower cultivation, thin the seedlings early to prevent seedlings from crowding each other, which affects the cultivation of strong seedlings and even later yield. As for saline-alkali land and plots with severe pest damage, the time for final singling can be appropriately delayed. At the same time, sunflowers should also be singled early, which helps cultivate strong seedlings and also helps the flower disc develop. Final singling should be carried out when there are 2 pairs of true leaves.
Image: Sunflower
5. Cultivation and weeding:Sunflowers are generally cultivated 2 to 3 times, which serves to weed and loosen the soil, break up crusting, conserve water, reduce evaporation, and lessen salt and alkali damage. The first cultivation is carried out at the 1 to 2 pairs of true leaves stage together with thinning and final singling, the second cultivation is carried out 1 week after final singling, and the third cultivation is completed before the rows close, together with ditching, earthing up and fertilizing.
6. Ditching and topdressing:Sunflowers rather like fertilizer. Ditching and topdressing is usually carried out at the third cultivation, mainly with nitrogen and phosphorus fertilizer: 5 kg of diammonium phosphate and 10 kg of urea per mu, mixed evenly and applied to the soil. Ditching and earthing up can effectively ensure the growth and development of secondary roots, prevent lodging, and reduce branching on the base part below the cotyledon node.
7. Timely irrigation:Sunflower irrigation uses the furrow irrigation method. Generally, for varieties with a plant height of 1.5 m, the first watering should be carried out at the bud stage, the second at the early flowering stage, and the third at the grain-filling stage. For varieties with a plant height of about 2 m, the first watering is carried out 4 to 5 days before flowering (in severe drought, irrigation is earlier), the second 6 to 7 days after the first watering, and the third at the grain-filling stage.
8. Pollination management:Sunflowers have a low seed-setting rate from self-pollination and a high seed-setting rate from cross-pollination. During cultivation, artificial supplementary pollination should be carried out in time, using methods such as matching flower discs, powder puffs, and cotton gloves to transfer pollen, or collecting pollen from the father parent and gently dabbing it on the stigma of the mother parent with a small brush. Pollination is carried out 3 to 4 times during the full-bloom period.
[Editor's concluding remarks]Sunflowers are cultivated in all parts of our country and have high cultivation value. Above, we have introduced the planting time and methods for sunflowers, and we hope this will be helpful to everyone!