Your vincas could well bloom longer than those mums.

The pink/white vincas are considered annuals by the way. The scientific name is Catharanthus roseus, not the same as Vinca that we see as a purple flowering ground cover. It is one of my favorite and most dependable annuals for our hot summers.

I've seen them blooming even after a hard frost has fried their leaves, so even though they are a tropical plant they are pretty tough.

I've heard of them self sowing and coming up the next year, the problem is that they tend to come up way late in the year (like August).

That's true,John. I've had some self sow mid-season and expanded my bed of them with the newbies. I don't think all the color varieties are self-sowers but the whites were.