Lathyrus latifoliés
Everlasting Pea, Perennial Sweet Pea
You’ve seen this plant before! In sunny spaces, both in back yards and open fields, Perennial Sweet Pea, or Everlasting Pea, is a staple of summer. You can’t deny its gorgeous allure…sometimes pink, sometimes white, and sometimes so dark in color that it looks magenta, this member of the legume family can be a knockout—especially when its leaves and flowers are glistening after a rain.
I grew up in Philadelphia and I had Sweet Peas in my backyard. I always thought that my Mom planted it every year, but now that I’m reading about it, it probably just volunteered. It turns out that this flower started out as an introduction from Europe and was planted frequently in American gardens. Eventually it “escaped” into the wild and became a weed. Once it gets started, it can stay for a long time.
Everlasting Pea is a perennial plant in the Pea Family. It has a sprawling growth habit. Some sources call it climbing, or trailing, but you get the idea…the plant crawls across other plants, or sometimes up fences, using delicate tendrils to reach for new heights. It prefers sunny, moist locations but can tolerate dry soils, just like the ones you’d find in open fields and “waste places”.
This legume has showy, bilaterally symmetrical flowers that are borne on a short raceme. It also has winged stems–an important feature to look for when you are trying to separate it from other species. The bluish-green, alternate leaves are compound, with 2 leaflets per stem. The leaf margins are smooth, or entire. The flowers will eventually be replaced by long, flat seed pods that are similar to snow peas (see the photos below).
Despite the name sweet pea, this flower has no flower fragrance. My guess is that the person who named it just thought it was the sweetest little flower! And it is!
VIRGINIA WILDFLOWERS 
Sweet and charming these pea flowers. They grow and bloom very much like garden peas but, instead of producing edible peas, they just climb up a trellis and look pretty. I used to have vines growing up the wall in my herb garden but they eventually died out — or greedy robins stole the seeds.