All about growing sunflower
Sunflower in the shape of its inflorescence resembles a sun disk, for which many peoples call it a flower of the sun. In the early morning, it opens towards the rising sun and follows its movement until sunset. Sunflower, having come to the end of its life, freezes in one position, but always its flower hat is turned to the east. For this property, sunflower in many nations is a symbol of devotion. Today, sunflower confidently occupied its niche in summer cottages, not only as a food, but also as a decorative culture. It is used as a decor for the landscape, as a hedge, solitary landings, when decorating leisure corners, for compositions in floristry.
Sunflower in the plant system belongs to the aster family, the specific name is annual sunflower (Helianthus annuus) The homeland is the warm regions of North America, where wild-growing forms occupy significant areas in the prairies, coniferous forests, and lowlands. Of the 108 species of sunflower, more than 50 are cultivated in the Americas. In Europe, culture appeared in the 17th century. While in Holland, Peter the Great sent sunflower seeds to Russia. Gradually, sunflower, initially as an ornamental crop, and later as a technical and food crop, occupied vast areas in the warm Eurasian regions. At present, varieties and hybrids have been bred, the cultivation of which is possible in colder regions.
Annual sunflower - a single-stem plant up to 3-5 m in height. The culture has a very interesting root system that can withstand long dry periods of the summer season. In the cotyledon phase, the sunflower root grows rapidly and is up to 6-10 cm long, and by the phase of 3-4 leaves it lengthens up to 1 m. The root system is branched. The central core root of an adult plant grows in depth up to 3-4 meters, it is well resistant to soil drought. Lateral 2-3 orders depart from the central root. They are located parallel to the soil in a layer of 10-45 cm and extend from the central root to a distance of 2 m. The lateral sunflower roots are surrounded by a dense network of tiny roots that absorb water and nutrients. Root growth stops at the inflorescence phase.
The leaves and stem of the sunflower are rough to the touch, densely covered with bristle-like hard hairs. The leaves are simple, large, petiolate, dark green in color, cover the stem to the apex, which ends with an inflorescence (basket), consisting of 2 types of flowers: reed and tubular.
Sunflower yellow flowers of different shades. Varieties with yellow-brown flowers are found. After pollination, tubular bisexual flowers form fruits. Sunflower is a cross-pollinated crop. Some bred varieties may have several basket inflorescences on long peduncles growing from leaf sinuses.
Sunflower fruits - achenes. Elongated, wedge-shaped, top covered with a leathery pericarp with 2 well-developed cotyledons inside. It is in the cotyledons that accumulate reserve substances in the form of oil and proteins.
According to the size and weight of the fruit, sunflower is divided into 2 types:
- oilseed sunflower, it is distinguished by a thin black peel, high oil content in cotyledons (40-50% or more) and a small achene;
- food sunflower has a denser and thicker peel of the achene; the fruits are distinguished by size and reduced oil content in achenes (up to 25-30%).
Achenes are arranged in a circle. Their size varies from the edge to the center of the basket. The post-harvest period of rest of achenes is 1.5-2.0 months.
Varieties and hybrids of sunflower for growing in the country
Varieties and hybrids of sunflower by maturity are divided into early, middle and late. In suburban areas, it is more practical to grow early and medium grades. The cleaning period in this case allows you to qualitatively prepare the site for the next crop.
From early varieties of sunflower can be recommended for cultivating varieties SUR and Spring. They differ in a short growing season - 77-83 days, high oil content. Sowing in the southern regions with a long warm period can be carried out in 2 terms: May spring and repeated until July 20 to obtain a full crop. Rodnik is drought tolerant, tolerates hot, dry summers.
Early ripening sunflower varieties: Yenisei, Cruise, Buzuluk form a crop in 80-90 days. The low oil content of the Yenisei pays off with the highest, among early ripening varieties, yield of a clean core.
Early ripe sunflower varieties: VNIIMK-8883 improved, Cossack, Berezansky, Donskoy-60 with a growing season within 80-86 days. VNIIMK-8883 has been zoned since 1972 and has been successfully grown to date in the Volga region. Resistant to adverse weather conditions.
Middle early sunflower varieties: Flagship, SEC, Favorite, Master, Gourmet. The last variety is distinguished by very large seeds, and the taste of the kernel. Gourmet and SEC are confectionery varieties. They are used as nuts for cakes and other baked goods.
From mid-season sunflower varieties stand out Donskoy large-fruitedforming a large achene with a high quality core.
It is believed that the variety is more stable in the transmission of maternal traits. And this is the main mistake of gardeners in their relation to sunflower. Sunflower varieties, due to cross-pollination, form genetically heterogeneous seed material in which degradation processes predominate. Therefore, for propagation of sunflower varieties always acquire only the seed material of the first reproduction. All the following will be clearly heterogeneous: different heights, the size of flower baskets, extended ripening period of achenes, etc.
Unlike varieties, sunflower hybrids are characterized by high genetic uniformity, which contributes to the simultaneous passage of development phases (seedling, mass flowering, formation, ripening of the crop, etc.). Hybrids are more resistant to stressful weather conditions, diseases and pests, and form higher yields.
Currently, breeders are conducting focused work on the development of hybrid varieties of sunflower. For successful cultivation in the dachas of the southern regions and the middle zone of Russia and the CIS, we can recommend:
Early hybrids: Jupiter, Donskoy-22, Triumph.
Early ripening hybrids: PR64A86 / PR64A86, PR64A89 / PR64A89, Kuban-930, Pace, Hidalgo, Tremia, Leopard, with a growing season of 86 to 97 days. Resistant to fungal and bacterial diseases and plant parasite broomrape. They are characterized by cold and drought tolerance, which makes it possible to grow these hybrids almost everywhere. The Tremia hybrid is adapted to the northern regions. Forms high yields in 90 days.
Medium Early: Signal, Prestige, Arol, Forward with a growing season of 100-108 days. Forward is characterized by rapid development in the initial stages, which significantly reduces the dependence on high spring temperatures and lack of moisture.
Mid-season: Donskoy 1448, Guarantee.
When purchasing varietal and hybrid seeds for propagation, it is necessary to choose zoned, which will significantly reduce the size of crop losses from pests and diseases.
Environmental requirements for sunflower
Sunflower is a plant of regions with a long hot period, a sufficient number of sunny days, it is demanding for heat, lighting, soil fertility and providing moisture. The growing season of sunflower lasts from 80 to 140 days, depending on the variety. Therefore, sunflower normally grows and forms crops in open ground only in certain regions where climatic and agronomic conditions correspond to its requirements.
If, in general, the climate in the region is suitable for growing sunflower, but spring frosts are repeated annually up to -4 ..- 6 ° С, then agricultural experts do not recommend cultivating this food crop, especially medium-late and late varieties. For a long growing season (100-140 days), the crop will still not be full and will not ripen.
Sunflower temperature requirements
The best areas for sunflower are places without shading and constant winds. When shaded, the plants stretch, bend towards the sun, form small baskets of inflorescences and chopped achenes.
For the normal growth and development of sunflower, the required temperature is + 20 ... + 27 ° C. Seedlings are cold-resistant and can withstand air temperatures up to -5 ..- 6 ° С, but for germination they need soil warmed up to +8 .. + 12 ° С.
Sunflower Lighting Requirements
In relation to the length of sunlight, sunflower belongs to the group of neutral plants, but has a positive reaction to the length of the day during flowering. If the lighting intensity is high during this period, the sunflower earlier passes to the generative phase of development; in cold foggy-rainy weather, the process of entering the next phase is delayed. Harvest is formed and ripens at a later date. Therefore, it is advisable to sow sunflower in lighted areas, avoiding even temporary shading, and protected from the wind.
Sunflower moisture requirements
To form a vegetative mass that provides the plant’s generative organs with necessary nutrients, sunflower requires a lot of water, especially in the initial period of development, when the roots are in the upper soil layer, most often suffering from dry weather. However, sunflower is drought tolerant. In adulthood, he is not afraid of heat, since a powerful root system is able to extract water from the lower soil horizons (3-4 m). Sunflower needs regular watering before the flowering phase, and then their number is reduced. Watering is carried out on demand of weather conditions (long hot period, withering winds, etc.).
Sunflower soil requirements
Soil conditions with timely application of fertilizers do not play a radical role for sunflower. However, the culture prefers black soil, sandy loam, floodplain and loess soils. (Loess soils are macroporous soils containing calcium carbonates and exhibiting subsidence when soaked with water under load). Sunflower grows well on humus and deciduous soils. The optimal soil acidity is pH = 6.5-7.0-7.2. It does not tolerate heavy clay soils, acidified and saline.
Sunflower growing technology
When placing sunflower in garden crop rotation, it is necessary to provide for its return to its former place no earlier than 6-8-10 years. The longest break (up to 10 years) is necessary if there is a broomrape in the garden. Sunflower is best placed on predecessors with a shallow root system, so as not to drain the deep layers of the soil, the water of which is necessary for sunflower.
Undesirable precursors of sunflower from this point of view are alfalfa, sugar beets, perennial herbs. When selecting precursors, pay attention to crops that have common pests and diseases (soy, peas, canola, tomatoes, onions, beans).
The best neighbors and predecessors of sunflower are potatoes, sweet corn and others, which allow for the autumn preparation of soil for sunflower. An excellent neighbor are tall herbs when growing them outside the cultural revolution (near the hedge, in the wasteland).
Soil preparation for sunflower
The sunflower plot is prepared depending on the type of soil, the condition of the plot and its fertility. On all types of soil during autumn preparation, the site is cleared of weeds and tops of predecessors.
- The cleared area in regions with long warm autumn is usually dug up by 15-20 cm. Heavy soils are also subject to digging. Before digging, it is necessary to add loosening materials: humus, compost, peat.
- Light (deciduous, sandy) soils can not be dug. Cultivate or deep hoeing at 8-10 cm, sow autumn green manure and, when receiving a green mass of 6-8 cm in height, plant them in the soil. Siderata can be left until spring. In the spring, mow and plant in the soil or immediately dig it no deeper than 10-15 cm.
- If the garden bed of cultivation in previous years did not receive organic fertilizers, then humus or mature compost (0.5-1.0 bucket / m²) is introduced in the fall.
- If necessary, mineral nitrogen-phosphoric or only phosphoric tuks, respectively 30 and 40 g / m, are brought under digging with or without organic matter.
- On chernozems, you can not use organic matter, but make a full mineral fertilizer (nitrophosphate, azophosphate, phosphorus-potassium), approximately 50-70 g / m². When applying potash fertilizers, it is necessary to use potassium sulfate, since sunflower negatively relates to chlorides.
Preparation of sunflower seeds for sowing
For sowing, seeds of the first reproduction in varieties and the first generation in hybrids are always used. Given that sunflower is a cross-pollinated crop, an ordinary specimen that has nothing to do with the mother plant can grow from the collected home material. Therefore, it is better to use purchased planting material for sowing.
- For sowing, one fraction of sunflower seeds is selected, which contributes to high simultaneous germination of plants (not extended over time).
- If the seed was purchased at the store, then it does not need preparation for sowing, since all the procedures have already been carried out by the corresponding company.
- If sunflower seeds are harvested on their own, then it is necessary to etch off fungal and bacterial diseases. Of the protectants, you can use the preparations Vincit, Scarlet, Winner, TMTD. To protect sunflower crops from wireworm, Gaucho is added to the solution.
- At home, it is safer to disinfect sunflower seeds in a solution of potassium permanganate or bactofite and, after drying, treat it in any growth stimulator - immunocytophyte, root, etc.
The timing of sunflower sowing depends on the climatic conditions of the region, so the binding of sowing seeds is best determined by the temperature of the soil in the sowing layer. The soil temperature in the 5-7 cm layer during the week should be at least 8 ° C. The optimum is +10 .. + 12 ° C.
Sown sunflower seeds germinate at an ambient temperature of +16 .. + 25 ° C. If the temperature goes beyond the specified limits, you can not get shoots. The second indispensable condition for obtaining friendly seedlings of sunflower is sufficient soil moisture. However, when waterlogged, the seeds undergo putrefactive processes and lose their germination.
Interesting! In the soil, sunflower seeds retain their germination up to 12 years.
It is better to use a nesting scheme for sunflower sowing at home, observing a distance between nests of 35-45 cm, and between rows of 0.7-1.0 m, depending on the variety or hybrid. Thickened plantings chop the size of inflorescences and seeds. The depth of planting of sunflower seeds is 3-4-5 cm. 2-3 seeds are placed in each nest. When deploying the 2nd pair of leaves, the crops are thinned, leaving the strongest seedling. Weak seedlings cut. Do not pull out so as not to damage the root system of a neighboring plant.
Sunflower seedlings appear on the 8-15th day.With in-depth sowing, seedlings can appear on 20-25 days. When sowing, you can add 10-15 g of ammonium nitrate directly to the hole, which will accelerate the appearance of sunflower seedlings.
A long pre-emergence period of sunflower and slow growth in the first phases of development, wide aisles, provided for by the sowing scheme, contribute to the development of weeds that inhibit the crop, especially immediately after germination. Therefore, systematic loosening of the soil is necessary in order to destroy weeds. They are carried out:
- in the phase of sunflower seedlings;
- after 2 weeks, more precisely - with the formation of 2 pairs of leaves;
- when the 3rd pair of leaves appears, the loosening of the row-spacings is deepened to 10 cm; during this period, you need to huddle the plants to better strengthen the root system;
- the next cultivation is carried out in the phase of 5-6 leaves; by this time, plants reach a height of 30-40 cm; loosening is stopped when the growth of sunflower reaches 70-80 cm or when the rows are closed.
- During the flowering period, it is necessary to re-earthing up or establish supports under the tall bushes of sunflower.
Sunflower top dressing
Sunflower top dressing begins with the development phase of the 3rd pair of leaves. In the first top dressing, 20-30 g of superphosphate and 5-10 g / m² of ammonium nitrate are introduced between rows.
The second is carried out at the beginning of the formation of baskets. Considering that sunflower uses large amounts of nutrients for crop formation, it is necessary to add 2 cups of wood ash and 30-40 g of azofoska or mullein infusion diluted with 1:10 water in this phase per m². On a bucket of working mullein solution, 20-30 g of potassium sulfate is added. It is during the formation of flower baskets that sunflower needs increased amounts of potassium.
The third top dressing with potassium sulfate is carried out in the ripening phase of sunflower seeds.
Some experienced gardeners advise when planting sunflower seeds to provide plants with nutrition immediately for the entire growing season. This technique is best used on soils with medium to sufficient nutrients. Prepare a nutrient mixture by mixing compost, wood ash and azofoska at the rate of 0, 5 buckets of compost a glass of ash and 2 tablespoons of azofoska per m². The mixture should be applied directly for sunflower sowing or distributed over the planting holes.
On depleted soils, it is more advisable to use the above or other feeding scheme, stretched over time.
Sunflower is a heat-and drought-resistant crop; it does not require constant watering. They start watering when the top soil layer dries by 2-4 cm. At the same time, during periods of growth of 2 to 4 pairs of leaves, the formation of a basket of sunflowers, budding, mass flowering and seed filling, abundant irrigation with a fairly high rate is required. Irrigation water should moisten the soil to the depth of the main roots. Frequent watering with small norms will not provide the desired effect. With a lack of moisture, accompanied by rapid aging of the leaves, the oil content in sunflower seeds significantly decreases.
Sunflower protection against diseases and pests
Sunflower is a favorite pest culture. The sweetish taste of young achenes, stems and leaves with a pleasant smell attract more than 35 types of pests. About 20 types of fungal and bacterial infections attack plants from the time of germination and accompany them until harvest. In small areas, it is impractical to treat the culture with chemicals, especially in the later stages of development. In this case, it is better to use biologics that are harmless to humans: biofungicides and bioinsecticides.
The main diseases of sunflower are fungal, bacterial and viral diseases, including white, gray, coal, root and other types of rot, downy mildew, phomopsis, rust, verticillosis wilting, alternaria or dark brown spotting, mosaic leaves. Diseases harm all parts of the plant, which causes its death over time.
The main measures to protect sunflower from diseases when grown in the country is the observance of culture. When grown separately, spatial isolation from other crops with similar diseases plays a significant role.
In the early stages of the manifestation of diseases, sunflower can be treated with chemical preparations, but they are dangerous for humans and domestic animals. It is better to use biological products that are harmless to humans at home. Processing with these preparations is possible until harvesting.
Biofungicides are well combined in tank mixtures with bioinsecticides. Of the biological products against diseases, Phytosporin can be recommended, of various modifications (golden autumn, Olympic nano-gel, universal, anti-rot, extra, universal, reanimator and others). All modifications are directed against a fungal-bacterial infection. Some are able to save a plant with an advanced form of disease damage (phytosporin resuscitator).
Products treated with phytosporin-antigun can immediately be used as food. For other biological products, the waiting period does not exceed 3-7 days. Processed products are stored 2 times longer. All modifications of phytosporin increase the immunity of plants to reinfestation, stimulate growth and development, and are capable of destroying not individual species, but a number of fungal and bacterial diseases. In addition to phytosporin, biofungicides Haupsin double action, trichodermin, glyocladin, etc. can be used.
The most common sunflower pests are meadow moth, moth (moth), sunflower tenon, aphids, nutcrackers, scoops, crickets, weevils, spider mites, bedbugs. The roots damage the wireworm (the nutcracker beetle larva), the bears, the May beetle larvae.
Use at home more practical tank mixtures of biological products from diseases and pests. First you need to check for drug compatibility. When used in accordance with the recommendations, bicol, boverin, nemabact, antonem-F, actofit, avertin, aversectin-C, bitoxibacillin and others provide a good effect.
The main method of protection, when growing any crop, not only sunflower, compliance with agrochemical requirements for growing, which significantly reduces the number of pests and the level of infectious background of the garden plot. The saying is always true: it is more successful to prevent a fire than to put out a fire.
To save the harvest from birds, a long gauze bag is pulled on the sunflower hat. Long hanging edges will not allow birds to get to the achenes. There are other ways to protect.
On the 35-40th day after flowering in the sunflower seeds, the process of accumulation of oil is completed. There is an evaporation of moisture from achenes, they reach wax ripeness. The period of harvesting of sunflower comes when the inflorescence freezes in one position, tipping the basket with seeds to the east. At this time, the sunflower leaves dry out, changing color from green to dark brown. Shrunken, they hang on the same dark brown stalk.
Baskets of sunflower seeds are left to dry on stems if the weather is dry and sunny. In the raw, they are carefully cut and laid out in the shade for additional drying. When delayed with the harvest, to reduce losses, the seeds are shaken out in a substituted bucket. Dry under a canopy. They must be checked against debris, laid out on paper bags or bags made of natural fabric and stored in a dry place. Some gardeners rinse the seeds from dust and dirt before drying.