OK, I’ll admit that 40 degrees isn’t exactly what most would consider frigid. But if you were an iguana it’s probably more than you could stand. The reason I am talking about iguanas and 40 degrees is I thought you might enjoy a report from the tropics for a change.

This comes from Boot Key Harbor at Marathon in the Florida Keys where the coconut palm trees sway and the bougainvillea blooms with lush abandon. I’m down here for a few weeks aboard our boat Old Salt. It is also where iguanas have set up shop to the dismay of local gardeners. But an unusual prediction of 40 degree nights means a heavy shower of iguanas falling from the trees can also be expected.

Exotic and flourishing beyond all reason, iguanas ordinarily thrive too well in the southern portions of the Sunshine State. Iguanas are cold-blooded lizards (is that redundant?) and when the temperature plummets like it is predicted to do for the next couple of nights, the iguanas’ systems shut down and they lose their grip and begin falling out of the trees to the delight of area residents. Folks here may not like the cold, but they like the iguanas less.

Reports from gardeners here seem to agree that the iguana situation got much worse soon after Hurricane Andrew hit the state more than a decade ago. Either escaped or released, the big lizards began multiplying, and if you think groundhogs and deer are problems, think again when it comes to iguanas. Now the slithering critters are everywhere, and when it comes to diet, anything goes.

They strip plants, eat flowers and birds’ eggs, have nasty dispositions, hiss menacingly, and generally make themselves unwelcome. Also consider that iguanas usually grow to 6 feet or longer, can take off your finger with one nasty bite and not only climb trees with ease, but are also excellent swimmers with lung capacities that are the envy of pearl divers.

One of the hottest gardening products down here now is “Iguana Be Gone,” a reported pesticide-free, 100 percent waterproof and environmentally friendly safe iguana repellent. The spray-on concoction comes in half- to four-gallon size jugs. Applied to plants and “holes where iguanas may live,” the “Iguana Be Gone” is reported to keep the scaly lizards away. Plus it is also reported to keep those pesky little Key deer from gardens.

Despite the iguana glut in these parts, the local gardens are in their winter glory. Bougainvillea is in bloom now and the colors are spectacular. This is one plant that seems to thrive on adversity. The thorny, woody vines grow in coral rock, are extremely drought and heat tolerant, and excel in the searing sunshine.

Palms of all varieties grow here, but the handsome coconut palm has to be the premiere tree that simply says “tropics.” These and other palms also shrug off adversity, being drought and salt tolerant, bending to tropical summer storms with ease.

One of my very favorite tropical plants is silver buttonwood, which is another oft-used plant here in the Keys. Silvery, velvety foliage distinguishes this plant, which can be used as a shrub for hedges or allowed to form a nice and compact small tree.

The golden chalice vine commands attention with large golden-yellow blooms that are about 6 inches across. Plumeria or frangipani also is in bloom now with flowers in a range of colors. Mahogany trees have finished their blooming period, and have now produced sturdy pods that split open to reveal leaf-like layers of seeds that are spread by tropical breezes.

In addition to iguanas, gardeners here have to contend with poor soil. In fact most gardens here have solid coral rock just a few inches below the surface. Water is a precious — and expensive — commodity here, being piped all the way from South Florida down the line of keys. A cistern or water barrel is almost a necessity and of course there are the summer storms and occasional hurricanes that can strip leaves off trees if not blow them away entirely. Fortunately the normal warm weather year-round means that things don’t take long to grow. Most times of the year there is something in bloom.

In fact just about everywhere one looks there are flowers and color, and even though we are facing a frigid Arctic cold snap and a certain “iguana rain,” it is a pretty nice place to be this time of the year. So that’s all from the tropics for now. Wish you were here.

Lynette L. Walther is the recipient of the National Garden Bureau’s Exemplary Journalism Award and the Florida Magazine Association’s Silver Award of Writing Excellence. She is a member of the Garden Writers Association. She gardens in Camden (and Florida).