Firstly, wicking beds are best suited to veggies. Most veggies do better in wicking beds because of the low stress, constant moisture. Some root crops, like garlic, might be prone to rot in these conditions, however, we’ve not had problems! And your daikon radish might not develop to full size due to the shallow (generally 35cm or less) soil layer. They aren’t generally used for trees and other perennial plants although you might have a few strawberries and other shallow-rooted perennials in there and in saying that we have seen small fruit trees grow quite well in wicking beds, but as trees have extensive root systems and can create significant shade, their success may come at the expense of other plants in the same bed. The best thing is to learn about the types of conditions your plants like and maybe have a little fun experimenting. What works well for some may not work as well for other and vice versa.