A Detailed Guide to Winter Storage Methods for Grapevine Cuttings
After the cuttings are collected, they should be put into trenches for storage promptly. Before being placed in the trenches, they should be soaked in a 100-fold dilution of Xin Gaozhi Mo (New High-Fat Film). This prevents the cuttings from becoming moldy and deteriorating during storage, prevents moisture evaporation, protects against pathogen infection, resists freezing and preserves warmth, and improves sprouting ability.
The storage trench should be chosen on high ground with good drainage, a relatively low groundwater table, and in a shaded spot. The trench should be 1 m deep and 1 to 1.5 m wide; its length depends on how many cuttings there are, usually 10 m. After the trench is dug, first spread a layer of clean, wet river sand 10 cm thick on the bottom, then lay the cuttings in bundles in order, separating each bundle from the next with fine sand. After placing one layer of cuttings, spread another layer of wet sand 10 cm thick, and at the same time fill the gaps between the cuttings thoroughly to prevent freeze-drying. Usually 2 to 3 layers are enough. Another method is to place the cuttings into the trench at an angle, likewise filling the spaces between them firmly with wet sand. Finally, cover the cuttings with 20 to 30 cm of soil, and spray a 800-fold dilution of Xin Gaozhi Mo (New High-Fat Film) to preserve soil moisture, prevent water evaporation, protect against sun and drought, preserve warmth and prevent freezing, prevent the soil layer from crusting, and smother and isolate sources of pests and diseases. The top of the trench should be ridge-shaped to help protect against the cold.
The temperature inside the trench should be kept at around 1°C, and must not be higher than 5°C or lower than -1°C. The sand and soil around the cuttings should maintain 70%-80% humidity, that is, it should form a ball when squeezed in the hand and crumble apart when the hand is opened. When the trench temperature approaches 7-8°C and the cuttings show signs of heating up, the trench should be turned promptly and the covering soil reduced. If it is too dry, an appropriate amount of clean water can be sprayed in.