J.D. 1 Report post Posted August 15, 2017 Hello everyone, We recently rebuilt our garage including a second floor rec room, one foot from the property line with our neighbor. (That location is essentially where the old garage was, and is consistent with zoning regulations and our building permit.) The neighbor now wants to plant 4 king palm trees, with starting heights of 10-12 feet, on his side of the garage, possibly as close as a foot away from the garage. (The garage is only 20 feet from end to end on his side, so I don't know how he thinks that 4 king palm trees of that size will grow and flourish in such a small space, but whatever.) I'm wondering whether the king palm trees will have a negative impact on the concrete foundation of our garage over time. The foundation is 2 feet deep. I've read generally that king palm tree roots don't typically damage concrete very much, due to their thin diameter and tendency to grow in the path of least resistance. Our landscaper has recommended that we put a 3-foot deep root barrier (made of vinyl or plastic) underground to protect the foundation, and we're going to try to do that. I think that the people in this forum are probably very knowledgeable about this sort of issue, so I would greatly appreciate your thoughts and suggestions. Thanks very much. J.D. 1 Quote Share this post Link to post Share on other sites
TexasColdHardyPalms 3,009 Report post Posted August 15, 2017 You see a lot of palms right next to the pools all the time because of their noninvasive roots. Those palms will have zero effect on your 24" footer and installing a rhizome barrier will be a waste of money on your part. 5 Quote Share this post Link to post Share on other sites
DoomsDave 8,045 Report post Posted August 15, 2017 JD! Welcome! Texas cold Hardy is correct. I have lots of palms near my concrete, nary a problem. If you have other questions, feel free to send me a PM (Private Message.) 2 Quote Share this post Link to post Share on other sites
Pando 4,541 Report post Posted August 15, 2017 No problem with kings for a foundation that deep. However, a root barrier wouldn't hurt in case your neighbor wants to plant a ficus tree next. 2 Quote Share this post Link to post Share on other sites
DoomsDave 8,045 Report post Posted August 15, 2017 31 minutes ago, Pando said: No problem with kings for a foundation that deep. However, a root barrier wouldn't hurt in case your neighbor wants to plant a ficus tree next. Or the dreaded RUNNING BAMBOO . . . . 2 Quote Share this post Link to post Share on other sites
Phoenikakias 1,651 Report post Posted August 15, 2017 How about Rhapis, is it also harmless? Quote Share this post Link to post Share on other sites
TexasColdHardyPalms 3,009 Report post Posted August 15, 2017 Yea, Rhapis is less than harmless. 1 Quote Share this post Link to post Share on other sites
J.D. 1 Report post Posted August 15, 2017 Thank you so much to everyone who responded so far. I really appreciate it, and your comments provide a lot of peace of mind. I would welcome any additional comments, so please continue to respond if you have any thoughts! Quote Share this post Link to post Share on other sites
sonoranfans 1,578 Report post Posted August 15, 2017 Ive planted many palms and seen many old ones planted near concrete, and I planted a number near pavers which should be easier to lift. Palms just dont damage concrete. You will not have any problems with your garage foundation. Those kings will grow up and soon there will just be trunks and the crowns will be well overhead. 1 Quote Share this post Link to post Share on other sites
Pando 4,541 Report post Posted August 15, 2017 1 hour ago, sonoranfans said: Palms just dont damage concrete. You will not have any problems with your garage foundation. Those kings will grow up and soon there will just be trunks and the crowns will be well overhead. They don't damage the concrete, but they can move the slabs over time. In my case I have clear evidence of concrete walkways tilted by the roots of older king palms and by one queen as well. They don't have the destructive power of ficus roots, but palm roots still have to go somewhere as the palm grows large, and a slab that doesn't have rebar or reinforcement wire will start to move. Note that vehicle driveways and foundations are usually built very strong so palms won't have an effect on them. But it's a different story for unreinforced 4" walkway or loose pavers. Give it 15-20 years and the ground will rise up near the base of the palm trunk lifting all the pavers and walkways with it. Quote Share this post Link to post Share on other sites
Josh-O 2,614 Report post Posted August 16, 2017 my next door neighbor has a monster growing on top of a sewer clean out line, irrigation pipes and a stack block wall. so far so good with no damage being caused to either. 1 Quote Share this post Link to post Share on other sites
Jim in Los Altos 2,224 Report post Posted August 16, 2017 (edited) Absolutely harmless. These have been in the ground about fifteen years and there is no intrusion even in the nearby pavers. The roots conform to any hard surfaces. Edited August 16, 2017 by Jim in Los Altos 4 Quote Share this post Link to post Share on other sites
Phoenikakias 1,651 Report post Posted August 16, 2017 Washingtonias, which are warm temperate palms - adapted to dry summer, only devour concrete, when planted to closely, through extension of root zone above ground. But still no lifting of the slab after 30 years... Quote Share this post Link to post Share on other sites
Phoenikakias 1,651 Report post Posted August 16, 2017 Washingtonia nr 1 Washingtonia nr 2 Livistona mariae All three plants are way robuster than a king palm, yet no lifting of the concrete. 3 Quote Share this post Link to post Share on other sites
