How to Grow Chinese Yam with the Suspended-Hole Method? A Detailed Guide Anyone Can Follow at a Glance

AbstractDigging holes for suspended planting means making holes of a suitable size according to the tuber length of the Chinese yam. The hole-digging tool can be a ring-shaped soil shovel. Choose a field with high, dry terrain, a low groundwater table, and convenient drainage and irrigation. Dig the holes in late autumn or early winter, disinfect the cut Chinese yam segments, place them in a seedbed to sprout, and after budding put them at the hole openings. Apply an appropriate amount of cake fertilizer, urea, and diammonium phosphate per mu, cover with plastic film, and let them grow naturally. Later, build tripods and prune side branches in time.

1. Choosing the Hole-Digging Tool

1. Suspended-hole planting is a cultivation method in which, according to the length that the Chinese yam tuber extends into the ground, a hole of suitable size is dug so that the tuber hangs suspended in the hole. The hole-digging tool can be a ring-shaped soil shovel. The shovel head is made from thin steel plate bent into a semicircle with a diameter of 8-10cm, and the bottom of the semicircle is cut with 3 small triangular notches. The shovel head is 20cm long.

2. Attach a wooden handle to the shovel head, with a handle length of 180-200cm. Then, according to the plant spacing and row spacing of different varieties, dig holes in the field. Generally, for small plots during the slack farming season in winter and spring, manual hole digging can be used, while for large plots, mechanized tools are needed to dig the holes.

2. Soil Requirements

Hole planting can be done in fields with high, dry terrain, a low groundwater table, and convenient drainage and irrigation, but sand dune land and overly hard soil are not suitable for hole planting Chinese yams, because the clay component is less than 5%, while 95% of the composition is fine sand and coarse sand. After digging, collapse is likely to occur, and the cost of digging holes is also relatively high.

3. Digging Holes and Fertilizing

Choose late autumn or early winter, apply 10000 jin of decomposed barnyard manure per mu as base fertilizer, then plow the soil, and dig holes during the slack farming season from winter to the following spring. Before digging, lay out lines at a row spacing of 70cm, dig shallow furrows 6-8cm deep along the lines, then use the hole-digging tool within the shallow furrows to dig holes at a plant spacing of 25-30cm.

Generally, a hole diameter of 8cm and a hole depth of 100-150cm are suitable. The specific specifications are chosen according to the thickness and length of the selected Chinese yam variety. If it is Taigu Chinese yam, the hole depth can be about 80cm, but it must not be less than 60cm.

4. Selecting Segments and Disinfection

1. Selecting segments: For Chinese yam segments, healthy tubers with a diameter of more than 3cm can be used. The weight of Chinese yam segments varies from place to place, with small ones at 20-40g and large ones at 80-120g. Then cut the seed tubers into segments according to the standard length of 10cm, with each piece weighing 30-40g.

2. Disinfection: During the cutting of the segments, disinfection and sterilization should be carried out to avoid damage to the cortical layer on the Chinese yam segments, which helps increase the budding rate. Generally, cut the segments about 30 days before planting. The cut surfaces can be dipped in a layer of plant ash, or the seeds can be soaked for 15 minutes in a 300-fold solution of 40% carbendazim suspension concentrate, then removed and dried, which helps reduce infection by pathogens.

5. Sprouting and Planting

For the sprouting seedbed soil, wet sand and fine soil can be used. The suitable temperature for the seedbed is about 25°C, and buds will emerge after waiting 14 days. When the soil temperature reaches 10°C, planting can begin. When planting, first cover the hole opening with plastic film, press the surrounding edges firmly with soil, then place the seed tubers on the plastic film with the young buds aligned with the hole opening, which helps the tubers enter the hole and grow.

After placing them into the holes, cultivate soil into ridges 40cm wide and 15-20cm high. Combined with ridging, apply 200 jin of cake fertilizer, 20 jin of urea, and 30 jin of diammonium phosphate per mu, and mix them evenly with the soil. Because the seed tubers have geotropism, there is no need to cut or break the film on the plastic film. Generally, the Chinese yam tubers can pierce through the plastic film on their own and enter the holes to grow.

6. Later Management

When the seedlings grow to about 30cm, tripods can be built with trellis materials. During the vigorous growth stage of the plants, when many side branches appear, the basal side branches need to be removed in time, which helps reduce nutrient consumption and allows the plants to ventilate and receive light, improving photosynthetic efficiency.

7. Advantages of Hole Planting Chinese Yams

1. Hole planting Chinese yams can significantly increase planting density, by about 1/3, allowing 3500-4000 plants per mu, and the single-plant weight of the Chinese yam tubers will not decrease. Therefore, compared with traditional cultivation techniques, it can increase yield by more than 30%.

2. Hole planting Chinese yams saves labor compared with traditional conventional planting, avoiding the heavy work of digging deep trenches, and one hole digging can be used continuously for 3-5 years.