We've been discussing this a bit on another thread(darned if I know where!) In my experience, it does help older seeds... but (obviously) it won't change anything if the seeds are completely dead. There is no way of knowing, though until you try.
Stanb999 suggests using a 1/3 household bleach solution (1 measure bleach to 2 water). Soak the seed for 30 minutes, then dump into a seive and rinse. Plant in a sterile seed starting medium. I haven't tried it, but I will.
One other tip.. if you arent sure of your seed viability, pre-sprout them in damp paper towels. I soak a triple thickness of paper towel with room temp water, then squeeze it out so it's verybdamp, but not dripping. I scatter seeds on it, cover with another single layer of damp paper towel, then roll up loosely and place in a plastic bag. LEAVE THE BAG OPEN, and put it in a warmish place (on top of the fridge is good.. not in direct sunlight, or anywhere that might heat the seed above 95 degrees). Check every other day from about day 3-4. When the seeds start showing roots and sprouts, plant.
I use this technique for planting several hundred vine plants... assorted melons, squashes, pumpkins and cukes. It saves me about 80% in seed costs, compared to the traditional method of planting 5 seeds in a hill and then thinning out all but 1 or 2. And it gives me a crop about a week earlier, especially if trying to plant earlier than optimum.
Summerthyme
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