Saving Your Plants Without Slaying the Dragon
It is said that beauty is in the eye of the beholder-so while I enjoy having this unique, dragon-like visitor to my garden, others might shriek and consider the scaly clawed Mexican iguanas a nuisance. True, they are herbivores that are particularly fond of eating tropical plants, flowers, stems, leaves, and fruit. Therefore, any garden is very attractive, rather like a restaurant, for iguanas. If you want to make nice, hold out a hibiscus flower. (It is equivalent to offering a dog a bone.) I am comfortable sharing space with these prehistoric looking critters because they are not venomous and are not likely to bite people: I don’t mind if they consume a branch or two of my plants…. but my neighbors and a couple of readers, however, are highly annoyed with marauding iguanas that decimate entire prized plants in 15 minutes’ time.
Although most people find these animals fascinating, iguanas do sometimes create challenges for residents of the Riviera Nayarit coast. The two common species that live in our area are the Green Iguana, (photo above) whose color varies according to its primary habitat, and the fierce looking Black Spiny- tailed Iguana. 
(photo below) The Black Iguana is the fastest running of all the iguana species. The typical mature length of both of these terrestrial iguanas is 3-6 feet (90-180 cm) but I have personally seen wild iguanas in the remote jungles of Jalisco and Nayarit that were easily SEVEN FEET long! I thought I had been transported back to southern Florida and was face to face with an American alligator… they had to weigh 60 pounds apiece. It was not an isolated sighting: on every hike I stood in awe when I encountered these giants. 
Iguanas live about 15 years and seem territorial: they do dig to lay their eggs and tend to return to feed within a particular area. All iguanas share the characteristic of communicating via body language and head bobs, and all are excellent swimmers.
The downside to having your yard become iguana territory is that in addition to destroying landscaping efforts, iguanas also cause problems by digging nesting burrows that can undermine sidewalks, sea wells and foundations. Iguana feces are stinky, unsightly, and may harbor Salmonella bacteria. Because iguanas often prefer to defecate in or around water, it is not uncommon for an iguana to use a private pool as a bathroom area. Large adults may be aggressive towards people and pets if they feel threatened or cornered.
Plants that Iguanas love to dine on: If you have hibiscus, orchids, impatiens, nasturtiums, broccoli, beets, lettuce, squash or melons in your yard, the iguanas will come. I have found that growing these types of plants in clay pots to be less appealing to iguanas than when the plant is in the ground.
Plants that iguanas don’t like:
If you want to discourage iguanas from your landscape, try planting some oleander, citrus, or crotons. Iguanas also avoid toxic and thick-leaf plants such as bromeliads (aloe). Other measures that you can try to protect your plants are to enclose the plant with wire mesh or if you want to discourage iguanas from climbing fruit trees, wrap thin sheets of metal, such as aluminum flashing, around its base. You may also have luck with a spray mixture of 4 cloves of garlic and 4 hot peppers chopped and mixed with a bucket of water. Spray a couple of times a week around your plants to deter iguanas. I am unaware of any commercial poison that is effective except coyote pee that is available NOB. I have friends that reasoned that since the iguanas have keen eyesight, hanging an artificial owl bouncing around in the ocean breezes would make the iguanas too nervous to eat. It hasn’t worked but it looks good!
Even if the iguanas persist in dining on your plants, there is a certain cache to telling your NOTB friends and family: “Oh, I lost another rosebush to the three foot iguana that lives in our yard.” Exotic reptiles are just another unique perk to living in the Mexican tropics.