One of the easiest ways of controlling the spread of suckering shrubs is root pruning. That involves using a sharp garden spade to sever the connection of the root suckers to the mother plant. Just use the spade to cut down vertically at the desired distance all the way around the perimeter of the shrub. You can then remove the severed shoots and discard or replant elsewhere or share with friends.

Just cutting back the shoots will not stop them growing.....you have to physically remove them. And the plant will replace them over time.

You can do this any time you like although there is less chance of having the severed shoots 'take' or reestablish as a new plant if done too late in the season.

Thank you gardengal, I will try doing that. I will not be replanting the severed shoots so I will do it now.

thanks again,

One quick note on the shovel. Take it easy when you push it in. I went ~all in~ on a shovel with one heavy foot push - unbeknownst there was a large rock underneath. The vibration went through the shovel up my leg, etc. My knee got hurt somehow and I was hurting/limping for like 3 months straight. It literally took about 3 years, as between the original event till almost 36 months later, for whatever reason, every now and then, the pain that knee would come back. Learned my lesson for sure