I used all the known other methods, but I got some rare seeds that couldn't be replaced and I figured the absolute safest way to do it without any chance for human error was to plant them straight out of the refrigerator dry right into the very saturated soil which will be kept very moist till I see a sprout. And Even then I turn a 6 inch terra cotta pot with a hole upside down over the seed until it sprouts. My germ rate was already ridicuously high just soaking a seed for 24 hours, but I lost three (always soak seeds in seperate cups) due to stpid mistake. Now I plnat my normal seeds the same way. Germ rate is just exactly the same minus dropped seeds (one less trip to make wit a seed in yiur hand) and it seems like it takes longer but when you figure how long a seed sits in a paper twowel or how long it sits in a cup and then germs they are all about the same. It's just taking the no transplant to extreme. I won't even transplant a seed anymore. But to answer your question, wait 8 days. That's the longest I ever went. And then after 8 days I planted another seed in the exact same spot and sure enough, 3 days later I got a sprout, and the next day I got another sprout.