I'm currently in the middle of converting our back yard into a densely planted, mostly perennial garden. My neighbor who prefers a 'weed' free green lawn has planted a young cedar hedge along their side of the property, whereas I have planted bushing/clumping perennials like sea berry and black berry. However, I know these plants can/do send off suckers, some of which might make it into my neighbor's property and upset them or risk them using chemical control on the edge of their property. Trying to be a good neighbor about it, does any one have any creative ways to help block/reduce the amount of suckers that might make their way to unwanted areas? Will their cedar hedge be enough? Will densely planting a row of comfrey help block suckers from making it through? Do I need some sort of underground solid barrier, if so, how deep do suckers tend to go?