Question
Hi Marc,
 Could you tell me how close to septic tank lines I can safely plant a Pink Japanese Magnolia without the roots creating a problem?   Thanks--Don

Answer
Don -
Your M. soulangiana has the potential for getting quite large (30-40 ft. ht. & about 20 feet wide - depending on your climate & other factors).  Tthankfully, the roots are not invasive...actually quite shallow (about 2 feet) and rope-like.  

This is bad if you have sidewalk, curb, or lawn, but good if you have a septic system.  All-in-all, a good choice for planting near a septic system.


That said, I'd keep it back at a minimum of 10 feet from the lines...not so much to avoid root issues, but because there are things in the septic line that are not good for a tree, in concentration.   You can probably get it closer to the septic tank, if needed.

Hope it helps.  -Marc