This is my first year planting Lupins, I have had good growth with singular major stems now being followed by further stems. Q As the flowers turn brown and wilt, is it okay to prune back the bare stem?
Prune out any old/unwanted stems. Do this sooner rather than later and a second flush will develop. This will not be as tall as the first flush, but better than nothing. Keep a look out for Wooly Aphids. They totally cover the stems of lupins.