Cobaea scandens, or Cup and Saucer Vine, is a spectacular flowering vine, and when I see one in a garden, as I did recently, I wonder why we don’t see it in gardens more often. The common name comes from the shape of the flower, which is unusual in that when it opens it is a light green color and in a few days turns to purple.
Cup and saucer vine is a very vigorous and fast growing summer vine and would be an ideal choice to quickly cover a fence or trellis. It is easy to grow from seed and should be started indoors in the spring and then set outside when the weather warms. Black Gold Seedling Mix will give the seeds a great start. It is technically a perennial but should be treated as an annual here in the Pacific Northwest and anywhere else where winters are cold. The one drawback that I can think of is that it does not bloom until later in the summer, the last part of August/first part of September. However, I think the flowers are so striking that they are worth the wait. Even better, they are pollinated by bats in the evening hours.