In fact, some seeds, if properly stored, can be viable even after ten years. Some varieties of tomato seeds have even been known to germinate after as long as 16 years! Storing unused vegetable or flower seeds does require some care. To remain viable, seeds must not be exposed to any moisture or extreme temperature fluctuations.
Palmer amaranth seed is thought to remain viable for 3 to 5 years depending on soil moisture and climate. As previously noted, this species pro- duces large quantities of seed, thus every effort should be tak- en to ensure that any plants are found and destroyed before they set seed.
How long are seeds viable?
Many seeds have been viable for much longer, while some a bit shorter. It’s best practice to do a quick viability test to check your germination rate prior to planting when using older seed. (As a general rule, most annual flower seeds are viable for 1-3 years and perennial seed for 2-4 years.).
When I was researching we ran into the question “How long does it take for seeds to grow?”.
(As a general rule, most annual flower seeds are viable for 1-3 years and perennial seed for 2-4 years.) Ageratum – 4 years Alyssum – 4 years Amaranth – 4 years.
How long do pelleted seeds last?
Pelleted seed is best used within one year, as the pelleting process can reduce the seed’s longevity. Storage — Now this is key! Saving your seed properly is the first step towards your best germination success for next growing season. Unused seeds should be stored in a cool, dry location (ideal temperature of 50ºF at 50 percent humidity).
Properly stored seed can outlive their estimated viability by many, many years. A quick note: when taking your seed jars out of the refrigerator, allow them to come to room temperature before opening. This helps keep any potential condensation from forming.
Depending on the type of seed and its quality, you may be able to store them and use them next year or the year after. In fact, some seeds, if properly stored, can be viable even after ten years. Some varieties of tomato seeds have even been known to germinate after as long as 16 years!