my goodness, you're in Bilzen? I would LOVE to be in your part of the world right now! I'm a cycling fan and will be awake watching Amstel Gold at like 5:30 my time tomorrow morning.
I really like your beds and honestly the exposed clay I see in your picture reminds me a lot of what I have in my yard here in Tennessee. I think you should focus on top-dressing the bed with compost over time...because feeding the plants will give them the vigor necessary to spread roots and succeed in that environment. If at all possible try to encourage earthworms to come in and break up that soil as well. I would be concerned about harming the integrity of your beds if you started digging around inside.
