As spring arrives, many homeowners are eagerly anticipating the opportunity to get their hands dirty in the garden. As you look for new flower or vegetable seeds you want to plant this year, take a moment to also look at the seeds you may still have from previous years as those may still be viable. Fortunately, there's a simple solution – the seed roll test.

Here's how it works: take 10 seeds from the packet in question, place them on a moistened paper towel, roll it up, and put it in a partially sealed ziplock bag. Check the seeds periodically, ensuring the paper towel remains moist. After the designated germination period (as indicated on the seed packet), unroll the paper towel to see how many seeds have germinated. By extrapolating from the 10 seeds, you can determine the germination percentage.

According to Extension Horticulture Specialist Lisa Johnson, the germination percentage is a key factor to consider when deciding whether to use leftover seeds or purchase new ones. While some seeds may remain viable for up to five years, others, like onions, have a shorter shelf life of about a year. Additionally, gardeners should also consider factors such as improved varieties or disease resistance when choosing seeds.