If you have a Home Owners Association, you most likely signed a Covenant when you moved in.
Most HOA's charge a fee for maintaining and looking after the outside of buildings and the landscaping.
This means that the fee that you pay every year goes towards painting, fixing fencing, mowing lawns and so on.
In many cases, the HOA has signed a contract with a local landscaping company who owns the equipment used to maintain the gardens and lawns.
Agreements like that are generally worded to be unbreakable, and the inertia created by this carries along with it the lack of will to change.
Sometimes, it's necessary to be a little bit discreet. This is not
to say that you need to be subversive. Getting any bureaucracy to
change is a bit like getting the Titanic to change course. It takes a
lot of effort, and more time than you think.
Here is one way to get things moving, without getting kicked out of your residence;
When you see the guys show up with the mowers to mow the acres of pristine (water guzzling) lawn, run out to the parking lot and jot down the name of their employer from the side of their truck.
Most likely, it will also have the phone number.
Armed with that, go to the nearest phone (out of sight) and call the company, and pretending total ignorance, ask to speak to someone who will give you a quote.
When that person (usually one of the partners, if it's a larger company) comes on, introduce yourself and say that you're a member of your HOA. If they exclaim that they do the maintenance at the very HOA that you are a member of, express surprise.
Ask them if they do any xeriscaping, and if they ask you why, just explain that you're doing some research for a potential client.
If they say that they do xeriscaping, ask if they would mind giving you addresses of local clients (or ask to see their portfolio on their website, which saves you a trip).
In the off chance that they don't have any experience in this type of landscaping, ask them to refer you to some other contractors that do. Chat for a bit, then tell them you'll get back to them.
Rinse and repeat, until you find some good quality landscapers that actually know what you're talking about.
Visit the gardens they have xeriscaped, take lots of pictures, with the garden owners permission, and tell them what you're doing - trying to get your HOA to see the light.
Now you have the ammunition you need; not only do these companies actually build and maintain beautiful xeriscapes, you have the pictures to prove it.