Winter barley: Cultivation, harvest and yields
Barley is generally considered to be a rather undemanding plant in crop production that grows in various soils and tolerates even harsh weather conditions. Nevertheless, some special features of cultivation should be taken into account in the case of barley, and especially winter barley:
Location: Overall, barley does not make high demands on the soil and thrives on ground with a soil quality of >30. Barley does not have a very strong root system, so it reacts sensitively to unfavourable soil conditions such as soil compaction. On the other hand, it likes deep, well-moistened, slightly acidic to neutral (pH 6.0–7.0) soils that dry quickly and absorb warmth in the spring. Good water availability in the tilling stage is important for barley. The winter hardiness of barley is less pronounced. Locations with frequent frosts tend to be unsuitable as a result.
Tilling: Winter barley requires well-prepared soil for sowing. The seed bed should be fine and dense to avoid uneven emergence and ensure that the seed grains can receive sufficient moisture for germination. In addition, it is advantageous for the soil to be well loosened.
Crop rotation: Barley is not very self-tolerant, so that breaks in cultivation of one to two years are recommended. Suitable previous crops are potatoes, as well as legumes and maize for winter barley.
Sowing: In the case of winter barley, sowing is carried out in early autumn, from late August until the end of September, so that the formation of secondary shoots (tillers) is completed before winter. Ideally, an accumulated temperature of 800°C should not be exceeded between sowing and the winter solstice. For this reason, drilling should not be carried out too early at locations with warmer autumns and milder winters. In order to develop before winter, winter barley requires 50–55 days to form well-stocked plants with four to six tillers. Winter barley is well able to tolerate temperatures as low as ‑15°C during the winter months. The seed density is 400 germinable grains/m2 for 2‑row varieties, or 350 germinable grains/m2 for 6‑row varieties. The seed density should be selected so as to achieve an optimal ear density of 500–600 ears/m2 for multi-row and 700–800 ears/m2 for 2‑row winter barley. The seed depth should be 2–4 cm at a row spacing of 8–16 cm. When sowing, barley is husked and has a thousand-grain weight of about 40–50 g. The germination capacity is more than 90%. Rolling the seed is recommended to improve the contact of seed with the soil, as this promotes germination and field emergence.
Fertilisation: Since barley does not have a strong root system, its nutrient acquisition capacity is not very pronounced. Therefore, a good nutrient supply is important, so a basic fertilisation with phosphorus and potassium should be carried out before sowing, since larger quantities of nutrients are needed in the autumn and potassium improves the winter hardiness. In the autumn, a fertilisation of approximately 30 kg N/ha is necessary.
Plant protection: With barley, mechanical weed control is carried out by harrowing; after sowing and before emergence through so-called blind harrowing. Plant losses from the 3–4‑leaf stage are balanced out by increased tillering, with a 10% higher sowing density. In addition, the choice of variety can influence the plant protection measures. For example, hybrid barley varieties can reduce the risk of crops being affected by localised, soil-related fungal diseases, such as Fusarium. In addition, barley can suppress undesirable weeds such as black grass. The green barley leaf absorbs the red light which is necessary for the germination of black grass, leading to suppression.
Harvest: The barley is harvested when it is fully or overripe. During combining, attention must be paid to the weight (wind adjustment) and the activation of the de-awner. Barley is then stored with its husks on.
Yields: The yields of winter barley are between 50–90 dt/ha.