I've always had big dogs, my neighborhood "requires" it. When they are pups they want to chew, and more than once they discovered chewing on plastic pots. Eventually I learned. My success usually involved a couple steps.
1.) when a new dog arrives, I use one of the bitter apple sprays that are labeled as dog repellent. Ones labeled to help prevent chewing on furniture have worked well. They are sprays that taste bad to dogs. I spray all pots on the outside edge of my stands. I try to avoid trunks and foliage, just spray the pots. Over time re-apply as per directions. Especially if we had a lot of rain I would re-apply every week until I was comfortable the dog had learned to ignore the trees and orchids.
2.) make sure you have an abundance of chew toys, rawhide, Nyla bones, what ever your dog likes that is good for them to be chewing on. If the dog has free run to where the trees are - make sure there are chew toys in that area.
3.) until a dog is 2 or so years old, or for an older dog adoptee, until they have been around 6 months or so. Keep an eye on them. If they start to grab, or explore too closely to the trees, tell them NO. And then hand them a chew toy, to give them something to chew on. "No!", alone is not good enough, you need to re-direct them into an appropriate behavior.
4.) Make sure you spend enough time exercising your dogs. A bored dog is a destructive dog. Play with them.
I almost never had any problems with my dogs once they were past the puppy stage. When I adopted a 6 year old husky it did not take much time at all, maybe a week or two and I was able to trust her around the trees and orchids. Plants in pots are generally not something dogs are into.
* caveat - I did loose several hundred dollars worth of orchids in one afternoon, to a lab-st bernard mix, and a number of years later lost a few early in training trees to a rottweiler mix pup, nothing super valuable. Accidents do happen, but it was the first episode with the orchids & lab mix that forced me to think about how to help the dogs be good.