Q: Six years ago a landscaper planted three ‘Little Gem’ magnolia trees six feet away from our house. She told us that the maximum height would be six feet. Since then they have grown much larger. We’re concerned that roots might invade our foundation.
A: ‘Little Gem’ magnolia certainly grows smaller than the traditional Southern magnolia. I would consider its mature height closer to twenty feet, not six feet. It is true that the roots will spread beyond the drip line but I don’t think that necessarily means they will damage your foundation. The roots have little to gain by growing into or under the foundation. It might be possible to keep the trees small with yearly pruning but considering the long-term labor involved, I’d think about removing them.