I've been doing hugelkultur beds for 10 years. Im assuming you read that in the incorrectly titled thread that is spreading misinformation and confusing the subject.
If you properly build your hugelkultur bed by filling in every single last gap with compost, soil, leaves etc and then let it rest the proper amount(about 2 years) there is very little settling. If you go back and read the literature from the 60s when the term hugelkultur was coined you will see that it's common practice to put perennials in hugelkultur garden beds. Most of the early graphics actually show bushes/trees on most hugelkultur beds.
I've grown blueberry bushes, strawberry plants, and sage in hugelkulture beds for years with great success.