I have two wisteria pre-bonsai in containers. One is a American wisteria that I grew from a cutting and "recollected" from my friend's yard in late 2011. It has many flower buds and should put on an amazing show in the next few weeks. The other is a mystery wisteria that I collected from a ditch this time last year. I suspect that it is another Am. Wisteria based on the areas collected it and the smaller blooms. This is invasive Chinese wisteria country...the size and color of both plants' flowers tell me that they are the same native species.
Here's the problem: the plant I collected last year is already fully leafed out and sending out new vines, with not a single flower. Both plants are growing in similar containers, with the same turface mix, overwintered side by side in an unheated greenhouse, and had the same slow-release fertilizer regimen last year. I've read that too much N will cause wisteria to leaf without flowers, but I doubt that has happened here.
Is this the result of the newer plant establishing itself in a container? What else might cause it to skip flowering and leaf out so soon? I had hoped to have a pair of wisteria in bloom this spring before cutting back for styling.