how old is too old for cucurbit seed?

[habitat-gardener]

I still have squash, cucumber, and melon seeds from 2006 (and later)! I seem to buy one variety or another every year, grow it once, and then grow something else the next year. Many of these are varieties I'd grow again, and finally I have a bigger garden space!

Should I compost the older seeds? How old is the oldest cucurbit seed you've successfully grown to harvest? Any tips for germinating old seed? Is the baggie method useful for checking germination, and if so, how long should I wait before giving up on them?

[Shule]

Melon seeds should last longer than tomatoes, according to seed stores, but I really don't know. However, some poorly stored melon seeds, which I saved myself as a teenager, were no longer viable when I tried them after about twenty years.

If you keep squash seeds in a clay ball in a cave, they might last over a thousand years.

Good question. I haven't seen many reports from regular gardeners on really old cucurbit seed. I've seen plenty on tomato seeds, however.

[eyegrotom]

I have some melon seeds that are 6 or 7 years old that I started on April 15, so far 6 out of 8 are up.

[pepperhead212]

Funny that you mentioned 2006 - two years ago, while doing an experiment on the effects that GA-3 had on various seeds, I tested some 2006 seeds that I saved from Seminole Pumpkins, and every single seed (well over a dozen) germinated! So they were 12 years old, and still viable. And I found that cucurbits definitely benefited from the GA-3, and it has speeded up some of the notoriously slow Asian gourds I grow. And I had some old cucumber seeds, that were free, but all I can grow is County Fair, due to bacterial wilt. So those were the cukes I tried, one batch soaked in water, one in a H2O2 solution (1 oz of 3% to a qt solution), and the other batch in GA-3, 500ppm solution. The H2O2 helped slightly, but the GA-3 was the best, speeding them up, plus higher %.

[Gardadore]

Pepperhead, would you explain how you prepared your GA-3 solution? This is new to me and I did find it on Amazon plus googled more info. I see it doesn’t mix with water unless one adds a small amount of 70% alcohol. 500 ppm doesn’t help me that much as I have no idea how to get that concentration! Thanks!

[pepperhead212]

@Gardadore I got my GA-3 on ebay, cheaper than I could find anywhere else. I use a few drops of isopropyl alcohol to dissolve it, as you noted, before adding filtered water. I have a small scale that weighs to .1 g, and adding this to 200 g of water makes 500 ppm, or 1/2 g to a liter of water. What I actually did was mix it at 1,000 ppm, so that I could also dilute that for the 500 and 250 ppm solutions.

[Gardadore]

Have to adjust to working with grams and check my scale. So if I understand correctly you weigh out .1 gram of GA-3, add a few drops of alcohol and put that in 200 grams of water or use .5 g and add to a liter. Or does the .1 g or .5 g GA-3 include the alcohol?
Thanks for the clarification! Sounds like a good chemistry experiment!

[pepperhead212]

The alcohol is added as part of the liquid - after zeroing out (tare), the alcohol drops are added, to dissolve the crystals, then the water is added to 200 g, or whatever you would be making.

[pepperhead212]

The alcohol is added as part of the liquid - after zeroing out (tare), the alcohol drops are added, to dissolve the crystals, then the water is added to 200 g, or whatever you would be making.

[GardenGuy00]

I've successfully germinated decade-old cucumber seeds before, so I say give them a try!

[zeedman]

The WI 5207 cucumber seed I planted this year was from 2009, and still had 96% germination. And that was seed stored in a freezer bag, in a file cabinet, at room temperature (the house has AC over the summer).

Small-seeded cucurbits don't seem to last as long. West Indian Gherkins & Melothria scabra were both dead after 8 years. Presumably they would have fared better if refrigerated or frozen, but I presently don't have enough freezer room to store more than a few of the most important seeds.