I visited Clarks farm last weekend. His heirloom strain of blackberrys are impressive. They set a ton of sweet juicy berrys. They they have incredable root systems sending lots of new canes, sometimes 10’ or farther from this years canes. They thrive with almost zero maintenance other then occasanaly mowing over dead areas and to control growth. They are the best example of working permaculture I have seen locally.