Risk to (waste) water pipes from tree/shrub roots

Alternating with shrubs or hydrangeas, I could definitely imagine that.

I plan to plant holly as a hedge. However, not in the endangered area but along the street and a bit up the driveway, about 40 linear meters. I was thinking of female holly - Alaska (red berries in autumn) and would place a male holly as a standard tree near the terrace for pollination.

Hydrangeas are not really my thing. Besides, our property is too sunny for most species.

I need suggestions for a stone or gravel bed/shade bed. It is located between the house and carport, belongs to the endangered area regarding [Leitungen] and should contribute to breaking up the paved area. I can gladly post a picture tomorrow. I want to place exclusively three to four containers. I was thinking of seasonal planting. What do you think?
The paving will be in the color Muschelkalk.

As I said, everyone has their likes and dislikes. I really like hydrangeas. For ideas, I always search the internet .. google and then look at pictures. I can definitely imagine a gravel bed with occasional breaks using a piece of your paving, such "repetitions" create a coherent picture. You can also "underplant" the containers seasonally, a standard tree with seasonal flowers underneath.

I tried planting small shrubs underneath last year. At first it looked great but towards the end.... I just need to gather a few more ideas. At the moment I am mentally a bit exhausted when it comes to ideas and house construction. ops:

Summer flowers sometimes don't look as nice at the end. I have had good experiences with lobelias; they still look nice towards the end of the summer.

Thank you for the tip. I haven't thought about lobelias at all yet.