What should be done to heavily matted roots before transplanting?

To effectively prepare heavily matted roots for transplanting, slicing the soil mass vertically is crucial. This technique helps to loosen the compacted roots, allowing them to spread more freely once transplanted. When roots become matted, they can become girdled or spiral, which restricts their ability to take up water and nutrients after being moved. By making vertical cuts, you create openings in the root mass, encouraging healthier growth and reducing transplant shock as the plant adapts to its new environment.

Other methods, such as soaking the roots in water, may temporarily hydrate them but do not address the underlying issue of compaction. Pruning all roots entirely can cause significant stress and shock to the plant, potentially leading to its decline. Leaving the roots as they are, without any intervention, could hinder the plant's establishment in a new location due to continued root entanglement. Thus, slicing the soil mass vertically stands out as the most effective strategy for ensuring a successful transplant.