We have a very tall conifer that has gotten it's roots into our septic system, we're going to have to get it taken down soon but it provides shade and privacy for our yard and I'd like to plant something next to it that can replicate a little bit of that, tall fences are not allowed by our HOA. So I need something with a shallow, fibrous root system that is not especially water seeking or far spreading, around 4-5 feet around or so. I am working on a cottage garden aesthetic so have been thinking about lilac but now am leaning more towards a purple smoke bush. Anyone have experience in a situation like this or ideas of what would work?

https://inspectapedia.com/sept...

Sorry but I don't recommend any tree planted near the septic system, roots can cause a lot of damage!!

Copper sulfate in the drains periodically will keep roots out.

well what do you mean as far as distance? Is it like 5 feet away? 10ft? Also what do you mean by septic system? Do you mean a leech/drain field? Or just the pipe that carries the waste to the tank? If you are in a HOA there is a good chance you are on public sewer system so no leech field. (?)

We had a drain pipe that got clogged with roots. Dug it up to find that it was too shallow, had been cracked and they used that thin worthless pipe, not schedule 40 I guess they saved a whopping 10 bucks at the time So we replaced it with 40 and no roots are going to get into that stuff. We had a HUGE elm tree 10 ft from our tank and we cut that down of course. Now if you are talking about a drain field, that is a different matter.