It is important to keep the food fresh because finches can be picky eaters. Nyjer has a thin shell and is vulnerable to spoilage while in the tube. Once seed starts to get moldy or becomes stale, finches will look for fresher forage.
Replace Nyjer in feeders every three to four weeks if it is not being eaten actively. Store your Nyjer cool dry spot for a longer shelf life, and buy in quantities that will be used up in a few weeks.
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