How to manage strawberries in autumn? Master these technical key points
1. Apply sufficient autumn fertilizer. Strawberry roots are relatively shallow and quite sensitive to fertilizer, so fertilizers such as ammonium bicarbonate and ammonium sulfate should not be applied; urea and compound fertilizer should be the main types. After the Autumn Equinox, apply 25 kg of compound fertilizer per mu as a top dressing to promote flower bud differentiation. Winter fertilizer can be applied in furrows in late autumn, mainly using thoroughly decomposed human manure and urine, to improve the plants' overwintering ability.
2. Foliar top dressing. Foliar top dressing can increase the photosynthetic intensity of strawberry leaves, promote root development, and increase fruit yield. Usually combined with pesticide spraying, foliar sprays can be applied with 0.3%-0.5% urea, 0.3%-0.5% potassium dihydrogen phosphate, 0.03% manganese sulfate, 0.01% ammonium molybdate, plant nutrient solutions such as Zhibaosu, and other organic nutrient solutions.
3. Irrigate sparingly to prevent waterlogging. In autumn, water should be applied sparingly to prevent strawberry runners from growing vigorously and consuming large amounts of nutrients, which would affect soil fertility. At the same time, clear ditches and drain water to reduce soil moisture and prevent waterlogging damage.
4. Hill up soil and cultivate. The emergence of new strawberry roots has the characteristic of moving upward year by year. Therefore, after 1 year of strawberry growth, attention should be paid to hilling soil around the base, mainly before new roots emerge, and the thickness of the hilled soil should preferably leave the crown exposed. Cultivation can be carried out together with top dressing and hilling, and cultivation can be appropriately deepened when root growth is vigorous and before growth.
5. Prevent and remove weeds. Field weeding can be carried out through comprehensive measures such as manual weeding, mulching film to suppress weeds, and crop rotation. To reduce labor, herbicides such as 48% trifluralin emulsifiable concentrate, 40% simazine suspension concentrate, or 10% haloxyfop emulsifiable concentrate should be the main method.
6. Prevent and control diseases and pests. If there is a lot of autumn rain and high field humidity, strawberries are prone to diseases. The main ones include gray mold, leaf spot, verticillium wilt, viral disease, bud blight, powdery mildew, etc., which can be controlled by spraying 200-fold Bordeaux mixture or 600-fold 50% carbendazim solution or 500-fold 65% zineb wettable powder. Viral disease is mainly caused by aphids carrying and transmitting the virus, and can be controlled by spraying 1000-fold 10% imidacloprid solution to kill aphids. For pests such as cutworms, white grubs, and mole crickets, 1000-1300-fold phoxim solution can be poured for control, or 2000-fold trichlorfon solution can be sprayed for control.
7. Cover with rice straw. Protecting old strawberry leaves in late autumn is beneficial to the plant's nutrient accumulation and inflorescence differentiation. Generally, after irrigating once in early to mid-October, cover with rice straw about 30-50 cm in late October. When the average temperature stabilizes at about 10°C the following year, begin removing the overwintering cold-protection cover, and remove all of it by late March. During operation, do not break the strawberry flower buds; a bamboo pole or similar tool can be used along the strawberry ridge furrows to gently lift the cover open.
Jia Youjiang, Agriculture Bureau of Juancheng County, Shandong Province