Peach blossoms
Tricolored
Motif
What we commonly call plum blossoms in Japan are actually Japanese apricot trees (ume). Their flowers bloom in a range of colors, from pure white to vivid pink. Sometimes, you might see the three colours onto a single tree, just like the beautiful gradation seen on this obi. In such cases, it could actually be a peach tree, whose blossoms have a similar shape.
The flowers are matte, made of silk, and the background contains golden lamé which makes it highly reflecting the light. If you compare the photo above with the one below you can imagine the different aspects as the fabric is moving in the light.