I nver soaked mine and they sprouted in a vey short time. Mine wintered over without any protection and we did have quite a few cool spells almost to the point of frost and they look fine but still waiting to see if or when they bloom. I got the seed from my sister-in-law from Colorado and just stuck them in soil and let them take care of themselves.

Hi, I hear your pain! If your referring to the climbing moonflower that smells like heaven and has very large seeds, I've been working with them for many years, and spent a lot of money on the seeds.

The shell has to be scored so it can absorb the water and sprout. I've tried many different ways, and this year finally had some success. I used a toenail clipper to clip off the tip of the seed. Then soaked in water a day or so, and planted in coir. I actually got 50% germination!!

They're really hard to impossible to find in any greenhouse, I got one once really early in the spring from a grocery store greenhouse, went back the next year and was told the grower they got them from had a flop of a crop.

Good Luck!
Karen