Hay can be stored under cover for several months to even years, depending on the type of cover used and the storage conditions. High-quality tarps or specialized hay covers that effectively block moisture and sunlight can keep hay in good condition for extended periods.
Generally, well-covered hay can be stored for up to a year without significant degradation, provided the cover is maintained and there are no issues with ventilation or moisture buildup. However, the actual storage duration may vary based on factors such as climate, the quality of the cover, and how well the hay is stacked and secured.