By Johnmw
Dorset,
United Kingdom 
Hello again everyone - I really love Perennial Wallflowers (Erysimum Bowles Mauve) for their prolific flowering; I regularly deadhead and also give a good trim at the end of flowering but am always nervous about cutting too far down and ruining the next season's flowers - so I always end up with a very woody lower half.
I do realise they are not long-lived plants, probably about 3 - 4 years, but just wondered if anyone had any tips on maintaining bushiness down to the ground and if cutting into the thick stems produces flowering shoots or just kills them off.
16 Feb, 2013
Answers
Never given them a hard prune but I always take cuttings 2 or 3 times a year. they are really easy. chose a 3" non flowering shoot and cut/snap it off. remove all the leaves except for the top 4/6 and push the bare stem into gritty compost. I tend to put 6-8 around the edge of a small plant pot and then keep them in a coolish spot. about 6-8 weeks later most have rooted.
16 Feb, 2013
I binned my two year old one recently, having taken cuttings last year. It got very leggy and woody, but never stopped flowering throughout its entire life, even in the snow. They don't respond well to hard cutting back.
17 Feb, 2013
Very many thanks everyone - I'll give the cuttings a go.
17 Feb, 2013
They are prolific flowerer. I've had one in flower constantly for 2 years.
There's also a nice variegated leaved version which takes just as easily from cuttings
Just google (images) "variegated perennial wallflower" to see lots of photos
17 Feb, 2013
Why not try cutting back on one plant and see what happens, I understood you can't cut lavender back into the wood, but I cut one bit where it didnt show, and it did shoot again.
16 Feb, 2013