If you’re like me, every year around this time you start thinking about all those seeds that have been packed away since their moment of glory in the height of the growing season. Tucked away, perhaps not as neatly as you would like, and forgotten until the brighter days of winter ring that annual garden alarm clock. If you’re like me, you often let seed shopping get the best of you and can’t possibly find room for all those new tomato varieties you’ve found or dedicate an entire bed to the very beautiful but inedible flower varieties that were just too pretty to pass up. You may or may not have an elaborate collection of half used seed packets that has grown exponentially over the years.
This year, instead of giving your mish mashed jars of seeds a sideways skeptical look and ignoring the bulk of them once again, we are going to get proactive. Out of gratitude and respect for those hardworking farmers who have brought us all this good seed, nothing goes in the trash. Not until we definitely determine that some of our beloved seeds have truly gone past their prime.
- Paper Towels
- Plastic Bags
- Clear tape
Pick out your seeds that have been in storage long enough to have decreased in viability. For personal use, I generally don’t worry about anything within three years of purchase and will test seeds going into their fourth season. Onions, many herbs, corn and other seeds with a particularly short storage life would be the exception.
Tear off a piece of paper towel for each variety and wet them completely with water. Ring out the paper towel so it is damp but not soaked.
Count out how many seeds you would like to test of each variety. This is somewhat determined by the number of seeds available and what the seeds will be used for. When we test seeds for sale, we always test at least 100. For seeds that will be used for farm produce, I don’t need to be as precise and will test between 20-50 depending on the variety. When I am testing homegrown seed that may be smaller in quantity, rarer, and inevitably more precious, I will test 10 seeds just to see if they are viable. It is your choice but obviously the more you test, the more accurate your germination rate will be. Place the seeds on half of the damp paper towel in a grid pattern.
Fold over the rest of the paper towel so all the seeds are covered. Gently press down.
- Number of seeds being tested
- Date of germination test
If you have the original packaging available, include:
- The source of the seeds
- Company lot #
- Original germination rate
- How many days they claim for germination
This information is great to include in a garden journal and records. You will determine over time what companies are growing and selling strong seed that doesn’t degrade quickly. Adhere your label to the outside of the plastic bag.
Gently place the paper towels with seeds into their respective bags with the fold towards the back. Do not seal bags. Place them in a warm, safe place that will be accessible.
Check your seeds daily by seeing if the paper towel is still damp and if seeds have germinated. If it has dried out, lightly dampen it with a spray bottle or pouring a small amount of water on the edges and center of the paper towel. Check daily to see how many seeds have sprouted. If unsprouted seeds looks swollen with water, continue the germination test. Some seeds such as carrots, parsnips, and specialty flowers can take up to 3 weeks to germinate in soil but may be faster indoors.
Write down the number of sprouted seeds out of total seeds tested to determine the germination rate.
You’ve done it! Now you can clear out space in your seed collection and start the season fresh. Depending on the seeds, it is usually possible to subsequently plant your sprouted seeds after testing. With or without planting the seeds, testing old seeds will reduce wasted space in seed trays and garden beds alike. You can rest assured that your garden is set-up for success with vibrant seeds in every corner.