What bushes or hedges do I plant to keep iguanas away ?
Because our location in New York City is too cold to allow iguanas to survive on their own for much of the year, they aren’t a common problem for us here, as they are in South Florida. Consequently, we do not have a large database of experiential information on this subject, and our research into your question has found only plants they don’t care to eat and none that will keep them off your property.
Our sources agree that you are doing the right thing by trying to keep them away to begin with. Fencing can help. One thing is certain, however: shrubs and dense landscaping plants will attract iguanas, as they like to hide among them. There seem to be no plants that will truly keep them away.
The Institute of Food and Agricultural Sciences at the University of Florida (UFIFAS) has done some research on iguanas and their control, which is summarized here: http://edis.ifas.ufl.edu/pdffiles/IN/IN52800.pdf
The UFIFAS has also compiled a list of plants that either attract or are of no interest to Iguanas. Please note, that “ignore” in this case does not mean “repel.” It only means they won’t eat it. If your yard or garden contains many of the “attractive” plants, they may try even harder to get into it, so you may wish to rethink some of your plantings. The only thing this list notes as an iguana deterrent is dog hair. http://monroe.ifas.ufl.edu/pdf/Hort/Plants_that_Iguanas_and_Key_Deer_ignore_or_eat.PDF
As a response to a question from another Fort Lauderdale resident, the National Gardening Association wrote a brief piece on iguana control that may also be of interest to you. https://garden.org/frogs/view/55359/
Thanks for contacting us with this question, and good luck with keeping these unwelcome visitors away!