How to plant dwarf large-head oilseed sunflowers? A detailed guide to growing techniques

Prepare a plot of sunny, sandy soil, deep-plough it and apply plenty of base fertiliser, then level it and make field beds. Select some high-quality, high-yielding, strongly disease-resistant mid-to-late-maturing seeds and sow them into the soil, cover with soil and water lightly. After the seedlings emerge, carry out the basic management tasks of thinning and gap-filling, watering and fertilising, earthing up and weeding. In late September, when the stems and the backs of the flower heads turn yellow, they can be harvested.

High-yield field management and growing techniques for dwarf large-head oilseed sunflowers:

1. Check the seedlings and fill gaps promptly

To ensure a full stand, when sowing in hills you can sow spare seedlings between the rows, and when seedlings are missing, transplant promptly to fill the gaps; when transplanting, plant with water or transplant promptly after rain.

2. Inter-row cultivation, weeding and earthing up

Oilseed sunflowers need to be cultivated 3 times during the growing period: the first cultivation after the seedlings appear, to a depth of 5-8 cm; the second cultivation after thinning is finished, to a depth of 8-12 cm; and the third cultivation before budding, to a depth of 12-15 cm.

Chemical weeding:

Besides manual weeding, chemical weeding techniques can be used, preferably as a soil treatment after sowing and before emergence. The following chemicals can be chosen: 33% cactril at 150 g per mu or 48% trifluralin at 100 g per mu, which give good weed control. Foliar treatment can also be used, with the following chemicals: 10.8% haloxyfop at 30 g per mu or 8.8% quizalofop-p-ethyl at 30 g per mu.

3. Fertiliser and water management

Oilseed sunflowers are relatively drought-tolerant and generally do not need irrigation, but under severe drought with access to irrigation water, water 1-3 times. Apply 10 kg of diammonium phosphate and 200 g of Youli boron-zinc per mu as base fertiliser; top-dress with 15 kg of urea and 100 g of Youli boron-zinc; spray twice with 10 g of Ruipelle at 3000 times dilution and 60 g of Ciba monopotassium phosphate at 500 times dilution, once every 7 d.

Weed promptly at the seedling stage; in the early growth period, unless there is exceptional drought, water as little as possible to encourage deep rooting; water promptly according to soil conditions at the early budding stage; and when drought occurs at the grain-filling stage, plots with irrigation access should be watered promptly. Oilseed sunflowers dislike waterlogging, so when sowing you should consider timing flowering, pollination and the mature harvest period to avoid the rainy season. Fertiliser rates are generally: per mu, apply 10-15 kg of urea, 10-15 kg of diammonium phosphate and 10-15 kg of potassium sulphate as base fertiliser, or 30-40 kg per mu of a three-element compound fertiliser. Top-dress with 5-10 kg from budding to flowering; the amount and method of fertiliser application can also be arranged separately according to local conditions.

4. Removing branches

This means removing the extra flower buds below the branches, leaving only one flower bud per plant, to ensure the sunflower grows normally and to prevent oilseed sunflowers from developing multiple flower heads on a single plant as they grow, which would rob the main flower head of the nutrients its seeds need.

The principle to follow when removing branches: “remove only branches, not leaves”.

When removing branches, handle them gently and do not damage the stem or leaves of the main stem. The leaves carry out photosynthesis and supply nutrients to the flower head, so generally do not remove leaves, to prevent a reduction in yield.

5. Artificial supplementary pollination

Because sunflowers are cross-pollinated, this means that when pollinating by hand we must use flowers from different plants to pollinate each other.

You can keep bees near the oilseed sunflower plot and use the bees for natural pollination. The best number of hives to set up is 4-5 hives per mu. At the same time, when bee sources are insufficient, carry out artificial supplementary pollination promptly.

Timing of artificial supplementary pollination: carry it out once every 3-5 days, for a total of 2-3 pollinations, choosing times preferably between 9-11 am and 4-6 pm. Do not pollinate by hand on cloudy or rainy days; this can reduce the rate of empty sunflower seeds.

6. Regular patrols

Pay special attention to birds and livestock eating the oilseed sunflower seeds, and patrol the sunflower field regularly every day, solving problems as soon as they are found.

The above is an introduction to dwarf large-head oilseed sunflower growing techniques, and we hope it is helpful to everyone.