For those not familiar with the plant, here's my source image.
I wish I had a better answer for the length of the blooming season, as
@Murky asked. At a guess, in any one location, maybe a couple of weeks. Maybe more.
I found a pretty good description of it from a grower's/gardener's perspective here:
https://plants.ces.ncsu.edu/pl...
There's basic info on it in the NGA database page for it,
Perennial Sweet Pea (Lathyrus latifolius), but flashing alert about one piece of info there. The plant spread is NOT 3-6 inches. Because this is a vine-like perennial (to answer
@EscondidoCal's question), its 'spread' can be anywhere from the width of the vine, if it is climbing, to the length of the vine, if it is spread out on the ground. I've read that vines can reach 10 feet in length, but I believe 6-8 feet is more common. Since I see it mostly as a ground cover, it's hard to tell where one plant ends and another begins.