Testing Old Seed

[crmauch]

Thought I'd post a little about testing some old seed I'd found I had from 2007, with one seed variety from 2006, and a few varieties of saved seed that somehow I didn't note the year.

I thought almost all the seed would be dead, or just a low percentage on a few. I was actually pleasantly surprised how viable some of the seed was. To test the seed I wet a paper towel, wrung it out folded it and placed the seed inside the folded area and put the paper towel in a ziplock sandwich bag. Also (and I should know this from past experience), a 'germination test' ends up me rescuing the new seedlings and planting them up into pots or trays.

Some of my results:
Blacktail Mountain Watermelon (2007) [20 seeds]: 100%!

Royal Golden Watermelon (2007) [17 seeds]]: 59%

Orangeglo Watermelon (yr?): 0%

Baker Creek Wonderberry (2007)[20 seeds]: 50%

Birdhouse Gourd (yr?) [20 seeds]: 25%

Scarlet Runner Beans (2011?) [8 seeds]: 100%

Golden Hubbard Squash (2006) [16 seeds]: ~15%

So, I'd say if you have older seeds and time, it may pay you to try the seeds out to see if they're viable.

[ScottinAtlanta]

Good to know. Can you do that method with okra seed as well?

[Tormato]

Did you go beyond the germination, and see if they make it to viable plants? I'm trialing some older beans (~2007/2008). They geminate OK , but many are "headless".

Gary

[crmauch]

Originally Posted by ScottinAtlanta

Good to know. Can you do that method with okra seed as well?

Don't know, I've never grown okra. It works with most seeds. I did do one test many years ago comparing average germination in soil vs. paper towels vs. other substances using rose seeds. Some varieties of rose seeds weren't affected by soil vs paper towel and some germinated better in soil (all were in baggies so getting seedlings out was much more difficult in the soil.)

[crmauch]

Originally Posted by Tormato

Did you go beyond the germination, and see if they make it to viable plants? I'm trialing some older beans (~2007/2008). They geminate OK , but many are "headless".

Most of the seedlings I 'rescued' and planted successfully. Only a few that germnated didn't make it - less than 10%? (a guess, as I didn't track that information). As to why they're headless -- are the cotyledons getting ripped off when they try to thrust out of the soil?

Scarlet Runner beans don't bring their seed leaves out of the soil (like peas), and I usually transplant them not long after I see a root leaving the seed coat (sometimes the root is up to 1 inch long, but usually sooner).

I did have some trouble with some brand new seed of Hyacinth bean (though not in same genus, the seedlings grow much like garden beans). The packet only came with 6 seeds, and I started 4 directly in pots (presoaked seed). Only one germinated and the other three rotted). Wanted at least two plants, so I tried a second batch with the two seeds w/ the baggie method. One worked beautifully, but the other came up but hadn't lost it's seed coat. Tried to pry coat off (and I may have gotten a little off (memory not clear)), but most of it stayed on almost like the helmet head you get sometimes with pepper. Eventually the plant managed to get its true leaves out, but because of the struggle to get them out and the fact that the seed leaves didn't get to photosynthesize (this is my conjecture), the leaves and plant are much smaller.

[Tormato]

The cotyledons are fine. There's just nothing between them, on some of these older "seedlings".

Gary

[Master_Gardener]

I've been studying seed storage. I am convinced that you can safely store most seed for decades. In my recent Master Propagators class we successfully germinated and potted seed that was 15 years old.

For most (Orthodox) seed, the enemy is heat and humidity. You should be able to store viable seed in your refrigerator for a very long time. Stored on a shelf in your garage, the shelf life may not be even one year.

Russel

[Master_Gardener]

Want to store seeds for over 50 years?

Seed Storage

[crmauch]

Originally Posted by Tormato

The cotyledons are fine. There's just nothing between them, on some of these older "seedlings".

I don't know that I've ever seen that. I've had seedlings come up that had no chlorophyll, and I've had 'weird'/deformed seedlings, but I don't recall any with normal cotyledons and no leaves.

[Tormato]

No first set of leaves, on these "headless" ones. If I wait awhile, sometimes the first set of true leaves will emerge and the plant will struggle, but make it. It's usually about a 50/50 chance, likely depending on good weather. On my oldest seed, it's probably about 3-4 out of 100 seedlings that are headless.

I'm wondering if one reason I see headless seedlings is because most of my bean trials are not yet stable varieties (F3's-F6's).

Gary

[crmauch]

Originally Posted by Tormato

No first set of leaves, on these "headless" ones. If I wait awhile, sometimes the first set of true leaves will emerge and the plant will struggle, but make it. It's usually about a 50/50 chance

Now that you said this, I may have seen this phenomenon, but with Golden Hubbard Squash -- two of 3 seeds came up and did not progress beyond the seed leaves for a long time. 1 of the two (which was planted earlier, did not make true leave growth for a long time. the 2nd died when I tried planting all three outside.