Storing Hay by the Bale
Proper hay storage preserves nutrients and prevents contamination and mold.
Your storage area should be:
Free of rodents
Off the ground (provide adequate air circulation)
Hay must be kept dry. Excess moisture can encourage the growth of molds that are damaging to your pigs' health. Putting hay in plastic bags is only safe and/or practical if the moisture content of the hay is extremely low. Ideally, choose a place free of mice, out of the sunlight and off the ground.
Exterior Hay Storage: Leaving hay exposed to the air (but not rain), allows the moisture content to be affected by the atmospheric humidity. You can tell if exterior humidity is a problem by noticing if mold grows in shady areas of your house and yard. Certain times of the year the humidity levels may be more acceptable (winter). Outside storage increases the risk of contamination from nesting mice.
Closed Container Storage: In order to store hay outside in an enclosed container, it must be thoroughly dried. This can be accomplished by keeping it in an air-conditioned, dehumidified space until the moisture content has dropped significantly. An air-tight container will slow the outside humid air from reaching it if it is not accessed too frequently. The small packages of hay sold in pet stores stored in plastic bags do not have mold problems due to the extremely low moisture content.
Storage in a climate controlled space is the most effective way to keep hay dry. See if there isn't a closet, porch or room corner you can spare. The author's hay is stored in a small enclosed front porch, on a wire rack that keeps the bales several inches off the ground. As you use hay, examine it to remove stray weeds and thistles.
Keep your bale in its compacted state as well as possible. Breaking open a bale and loosening the contents exposes the hay to air which will affect quality and dissipate the wonderful smells of fresh hay your guinea pig will enjoy. Some people break off a "flake" as needed to minimize air exposure, gradually using the whole bale piece by piece. The baled hay pictured at right is stored vertically to allow easy removal of a thin flake of hay while maintaining the compactness and integrity of the bale.
Whatever you do, don't forget about fresh grass which contains much higher amounts of vitamin C. Fresh clean grass is a treat for your guinea pigs. Choose grass from an area not frequented by dogs or livestock and away from heavily trafficked roads. Some owners describe ill pigs who will eat fresh grass while turning down other foods. Read about forages for more suggestions.
Interior Hay Storage
In a conditioned interior space, you may find a storage bin handy for day-to-day use. WEAVER uses a laundry bin sorter on wheels with the interior cloth partitions removed, creating one large storage bin:
She also uses a wicker laundry hamper with a cotton lining for bermuda grass:
Link to original thread: Tired of hay everywhere?
Thanks to WEAVER for sharing her hay storage ideas and contributing photos!