How to apply microbial fertilizers to autumn potatoes, and what are the benefits of using them?

　　Potatoes are one of China’s major food crops and require supplemental fertilization during their growth cycle. So, how should microbial fertilizers be applied to autumn‑planted potatoes? What are the benefits of using microbial fertilizers for autumn potatoes? Let’s take a look.

　　How to apply microbial fertilizer to autumn potatoes

　　Autumn potatoes have a short growing season and limited growth time, so it is essential to select early-maturing varieties with a brief dormancy period. Moreover, pre‑plant sprouting is a critical step in cultivating autumn potatoes. For seed potatoes, it is preferable to sow whole small tubers; if using larger tubers, they should be treated with thiophanate‑methyl or coated with wood ash, then allowed to dry before initiating sprouting.

　　During sprouting, dilute the microbial fertilizer with water at a ratio of 3 to 4 times, then immerse the potato tubers in the solution. After soaking, remove the tubers and spread them on a sand bed mixed with the microbial fertilizer (use 200–300 grams of this fertilizer per square meter of seedbed soil, thoroughly blended with sand). Arrange the tubers in a layer about 20 centimeters thick, then cover them and the surrounding area with a 5-centimeter‑thick layer of moist sand. When the sprouts reach approximately 2 centimeters in length, rake them out and transfer them to a cool, shaded location with diffused light for green-up. Two to three days later, plant the sprouted tubers on a clear morning or evening.

　　For autumn potato cultivation, the typical planting density is 5,000 to 6,000 plants per mu, with a seed rate of 150 to 180 kg per mu. A wide‑row, narrow‑plant spacing facilitates hilling; maintain a row width of 40 cm and a hill spacing of 25 cm, placing the sprouts downward and covering them with about 5 cm of soil. When the seedlings reach approximately 15 cm in height, perform hilling to improve soil aeration, enhance diurnal temperature variation, and promote high quality and yield.

　　Before planting autumn potatoes, apply a sufficient base fertilizer: apply 1–2 kg of microbial fertilizer per mu, thoroughly mixing it with farmyard manure, chemical fertilizer, or fine soil before broadcasting. After emergence, combine this with inter-row cultivation and soil loosening, applying another 1–2 kg of microbial fertilizer per mu—either alone or mixed with urea—to promote rapid seedling growth. In the mid- to late stages, foliar spray a mixture of microbial fertilizer and potassium dihydrogen phosphate to stimulate tuber enlargement in autumn potatoes.

　　Benefits of Applying Microbial Fertilizer to Autumn Potatoes

　　The planting area of autumn potatoes has been steadily expanding; however, the lack of widespread adoption of scientifically sound cultivation practices has resulted in a situation where acreage has increased but yields have remained stagnant. Applying microbial fertilizers appropriately during the sprouting stage and the late growth phase can effectively address this issue.

　　When cultivating potatoes, incorporating bio‑fertilizers into the seed treatment, as a base fertilizer, and as a top dressing promotes rapid germination, high germination rates, uniform sprouting, robust seedlings, and vigorous stems with lush green foliage. It also protects the plants from damage caused by root‑knot nematodes, late blight, soft rot, and wilt diseases, resulting in early and abundant tuber formation, well‑developed young tubers that remain free of deformities, neat tuber shapes, rapid enlargement, substantial starch accumulation, larger tubers, and delayed plant senescence. Consequently, both yield and quality are significantly enhanced.