Growth Characteristics of Watermelon Red Sweet Potato
Among various sweet potato varieties, the watermelon red sweet potato is highly favored for its unique sweetness and nutritional value, but many growers report difficulties in the cultivation process. The growth characteristics of this new sweet potato variety differ significantly from traditional ones, and only by accurately grasping its growth patterns can high-quality and high-yield be achieved.
Temperature Sensitivity and Countermeasures
Seedling Temperature Control
Experimental data show that when the soil temperature is stable at 22-28°C, the seed potatoes germinate the fastest. It is recommended to use black plastic mulch in spring cultivation, which can increase the soil temperature by 3-5°C. In the northern regions, using small arch sheds for seedling raising can shorten the seedling emergence period by 7-10 days.
Critical Growth Temperature
When the air temperature remains below 12°C for three consecutive days, the tuber expansion will completely stop. By establishing a temperature monitoring system and spraying cold-resistant foliar fertilizer 15 days before the low-temperature period, the growing period can be effectively extended by about 20 days.
Key Points of Light Regulation Technology
Photoperiod Management
During the tuber formation period (60-80 days after transplanting), maintaining 8-10 hours of light per day can increase the starch conversion rate. When using intercropping patterns, it is recommended to combine with short-stemmed crops (such as peanuts) to ensure 3 hours of direct sunlight at noon.
Light Intensity Demand Curve
Seedlings require a light intensity of 20,000-30,000 lux, which should be increased to 40,000 lux during the tuber expansion period. By detecting the leaf transmittance rate, adjust the plant spacing in time to maintain a light intensity of not less than 15,000 lux for the middle layer of leaves.
Water and Fertilizer协同 Management Strategies
Precision Irrigation Plan
Using a drip irrigation system to control soil moisture within the range of 60-70%, supply 15mm of water every 7 days during the tuber expansion period. In the rainy season, establish a three-level drainage ditch to ensure that waterlogging is removed within 24 hours after rain.
Nutrient Element Ratio
Apply high-nitrogen fertilizer (N-P-K=20-5-5) 30 days after transplanting, switch to balanced fertilizer (15-15-15) in the middle stage, and use high-potassium fertilizer (5-10-25) 40 days before harvest. Combined with humic acid fertilizer, the yield per plant can be increased by 18%.
By establishing a management system that integrates temperature, light, and water-fertilizer, the yield of watermelon red sweet potatoes can stably reach over 3000 kilograms per mu. Focus on controlling the day-night temperature difference (optimal 10-12°C) and potassium element (G-Y) during the tuber expansion period, combined with regular field inspections, can significantly improve the commodity potato rate. Choosing sandy loam soil and implementing a three-year crop rotation system can effectively prevent continuous cropping obstacles.