during the coming growing season the Wisteria will produce long shoots which can be trained if wanted for extension growth...if however flowers are wanted these new shoots should be shortened to about a metre long after the end of june...the very first gardening activity of the following new year your friend should undertake is to shorten those by now leafless shoots still further so that just two buds remain on each...the Wisteria should then flower its head off...do this each year .