I love herbaceous perennial climbers as I can grow them over other plants getting double value for the one spot. By their very nature they can only get so big in one growing season and then will die back again.
This South American species grows throughout the summer flowering as it goes well into the autumn with its tiny yellow Nasturtium flowers with fine red veining. Its small bright green Oxalis like leaves are also entertaining! People will think you have a climbing weed!
At this point I must mention that this plant needs to be controlled if you can’t allow it its head as it suckers quite vigorously. It will grow to about 3 or 4 metres tall in any growing season so a fair sized shrub will make the best host or grow it though some other climber up a fence. In mild climates it can in fact be evergreen but I prefer to lop it off in the late autumn even if it doesn’t do it itself for tidiness.
I have plants in 15cm. pots at $18.50 for the brave amongst you!