I always find Ipomoea pandurata and many other Ipomoes infected with wevils....but there is always some good seed... I just throw way he infected ones. Ipomoea platensis produced some seed for me this year...did not have them in the ground as usual. Planted the seed upon harvest and have one seedling under lights. I leeve them in the seedling pots for a year at least a year the seeds will gernimate over a long period. Here in Illinois the best growth is with them planted out for the summer in rich soil. The tubers get really large then. Theis is not a caudiciform at all. but mearly a tuberous plant like any other sweet potato.