How to keep your yarn safe, stored and ultimately used. Whether you have a lot of yarn or a little yarn storing it properly will keep it in new condition until you are ready to use it in a project. Yarn is subject to some environmental factors whether you have a stash of acrylic or man-made fiber yarns or a stash of natural fibers.
Both types of yarn are vulnerable to sunlight, dust and humidity. In addition wool and wool blends are also sensitive to moths. Purchasing yarn is one of the simple pleasures of knitting, when you purchase yarn and bring it home all the possibilities are still there; it is a hopeful time. Therefore there is nothing more discouraging than finding the yarn you purchased last month or last year has faded or become infested with moths.
Prevention is much better and often the only way to go, because once a yarn is faded there is no restoring it to its original color or colors. Having your yarn on display is a lovely idea and can make a beautiful display, but you have to weigh the joy of display against the cons of exposure to the sun and elements.
A few obvious tips, buy some plastic tubs that are not see through, and if you want to know what is inside without opening them up label them and attach the label or list to the outside. Store these tubs in a cool dark place if possible, but definitely out of direct sunlight. The tubs serve another purpose in that they also generally have close fitting tops and keep moths out.
For yarn I absolutely have to have out to look at, touch, and just plain hang out with, I keep it in a basket, out of direct sunlight and shake it every now and again over a white paper towel to make sure moths have not gotten into it. The white paper towel will show the little bitty moth larvae.
If you have the unfortunate experience of having moths in your yarn, put the yarn in a plastic bag and freeze it for at least a week. Take it out of the freezer, thaw it out, shake it out again, and refreeze. If you are really afraid that moths will attack other yarn you can take the additional step when first purchasing the yarn of putting each batch into its own ziplock bag and then into the plastic storage bin. Or after freezing and refreezing, put the infected yarn into ziplock bags at this time before putting it back in your stash.
Again, you have to look at your space requirements, your environments moth population, how much direct sunlight your stash is exposed to and decide if you want to protect your yarn against these threats. The biggest deterrent to storing yarn in opaque bins is that it does become out of sight and therefore out of mind and then never used up. So it is, as with much of life, a balance issue.