Hi,
I planted my morning glories around March this year and transplanted them outside after the danger of a last sring frost has passed. I never knew you can sow them at first frost, because my
seed packet said to sow them in
spring after the ground warms.
If I were you, I would wait until next
spring to
plant them. Unless you have very mild, frost-free winter in your area, your August-sown morning glories will have a very limited time to grow before frost comes and kills them. MG's are annuals, so they can't survive winters (@least not here).
You should soak them for 24 hours, yes. Then either
plant directly outside or in pots. I planted mine in little pots and then transplanted...it worked...but that was just my experience. MG's are not too picky about soil, just some potting soil or topsoil would work. Put them in full sun! They love the sun! Don't water them too much either, they like fairly dry soil.
I have mine
growing on a fence and on this metal trellis thing (whatever you call it). You can use some wooden sticks or bamboo poles, stick it in the ground, and let them climb. They climb on everything...including
trees!
MG's are not picky
plants. They really quite tough and easy to care for. Any more questions, feel free to ask!
Good luck!