Your thrifty Planet Natural blogger has had good luck storing leftover seed (PDF) he’s purchased from year to year … except when he didn’t. Not too many years ago, we stocked up on spinach seed for all the repeated planting we’d planned. There was plenty left over — that summer was cool and damp, so our first crop took longer than we expected and our second crop barely leafed out before the first frost arrived. We stored our leftover seed as we usually do: inside its packet in a tightly sealed glass jar down in our cool basement.
When spring came around, we planted the seed we bought the year before, just as we’ve often done with the previous season’s extras. And even under near ideal growing conditions — we know because we kept track in our journal — we were rewarded with poor germination. The seed that did germinate didn’t do well, its leaves small and stunted. We wondered if we had too much nitrogen in the soil. Too much nitrogen often inhibits early germination of greens. But the lettuce we planted nearby, some of it from saved seed, did just fine. Could it be that spinach seed doesn’t keep as long as lettuce? (more…)