I live in a condo in New Westminster and we have 5 ornamental cherry trees planted in front of the ground floor patios. The trunks of two of these trees are within 5 or 6 feet of my concrete patio. 5 feet to the other side of these trees is a 7 foot cedar hedge. These trees are probably original to the landscaping of this building which would make them about 25 years old. The main trunks of the cherries are quite large being about 6 or 7 feet in diameter and the big roots are 8 to 10 inches above the soil level. The top of the canopy reaches up to the third floor. Underneath the concrete of my patio lies the roof of the underground parkade. Question 1... I would like to plant a shade garden underneath the canopy. I will need to bring in quite a bit of soil as it is nearly impossible to make a space to plant anything because of the extensive roots from the cherries and the cedars. Will covering the roots only encourage the cherries to sprout more suckers? Question 2 ....are the roots from ornamental cherries likely to cause damage to our parkade roof membrane or building. There is currently quite a bit of moisture leaking down the walls of the parking garage. Can't help but wonder if the roots are responsible and if over time as the trees continue to grow things will get worse. I would appreciate any advice on the matter. Thanks
I'm guessing that the cherries are grafted and that the rootstock is Prunus avium (mazzard). If this is the case, any root disturbance will probably cause further suckering, but increasing soil depth won't necessarily do this. The situation doesn't sound ideal. With respect to your water leaks. It would be mighty dangerous for anyone who hasn't investigated the problem thoroughly and in person, to suggest that the cherry roots are the cause of the leakage. It's certainly possible, but membrane technology twenty-five years ago (to say nothing of the quality of the installation) may not have been what it is today.
Thank you Douglas for your reply. To investigate the problem to whom do we turn to? An arborist, or an engineer?
I suspect you'd have to consult an engineer. If you're in a strata, you might first check with the strata management company.
