Hi Don and WELCOME
I have only grown portulaca from seed. I direct sow as the seeds are so tiny and it germinates well and grows well in the hot sun. I love Swallowtail nursery and have gotten seeds from them. I buy portulaca seed sort of everywhere. At the local box stores, from places like Swallowtail, etc. It always does really well for me.
I have never seen purslane seed. Only the plant and Lowes starts carrying here I "think" late April or into May..
I have no preference but for those like Becky that lives in AZ, she can pretty much keep purslane alive year round. Purslane is beautiful in hanging baskets for the way it grows.
I'll see if I can find some of my photo's for you.
