A Taste of the Tropics
- Judith Paul
- 6 days ago
- 5 min read
Updated: 2 days ago
Over the last few years, I have noticed an increasing demand for plants that have a tropical ‘look’. Many are meant for gardens around pools, but there is also an increasing number of homeowners who prefer this style regardless of whether they have a pool. The problem is that many regions within the USA are definitely not in the tropics. Happily, there is a way of achieving a tropical vibe without having to relocate nearer the equator!
The beautiful tropical hibiscus and Mandevilla plants that box stores and nurseries sell in the thousands won't survive outside through any winter in an area with winter temperatures that get below 50°F (10°C). You might be lucky to find a uniquely hardy specimen and plant it in a spot which – by a stroke of good luck or gardening genius – has its own little microclimate, but that’s the exception rather than the rule.
Bringing tropical plants inside to over-winter is possible, but it involves a lot of work re-arranging the house, moving containers, controlling insects from the potting soil, and – for plants that need it – setting up grow lights with the right spectrum. Some plants can cope with being brought into an unheated, uninsulated garage or porch for the winter, but this is riskier. Plants with tubers, rhizomes, and bulbs can be dug, cleaned, and stored in tubs or baskets with some sort of filler like peat moss, but this is an incredible amount of work that many busy homeowners simply do not have the time or energy to accomplish.
Greenhouses, conservatories, and lanais are options, but there is a cost to getting them set up, and in most colder regions (including NC), many truly tropical plants will probably also need a heat source, which requires management throughout winter. If there is a power outage or a storm damages the structure, you risk losing everything inside your greenhouse. There are ways and means of storm-proofing a greenhouse so that plants are safer, but all of these require research, time, money, and effort to install and use effectively.
First of all, what is a tropical growing zone? Well, back in 1927, a taxonomist at The Arnold Arboretum called Alfred Rehder created the first hardiness zone map for the continental USA. That map is now maintained by the US Department of Agriculture. Other countries have their own version, so if you are in the UK, Sweden, South Africa, or New Zealand, you should be able to do an internet search to find and use a hardiness map prepared and maintained by a credible (usually agricultural) organization for your area. Here’s a link to the US version - https://planthardiness.ars.usda.gov/. It has a handy-dandy function that you put your ZIP code into to find out what your exact growing zone is.
In the US, tropical zones are generally considered to be Zone 10 and up. There are very few areas within the US that fall within a ‘true’ tropical climate (with high humidity), but there are plenty that are hot. There is a difference! Southern Florida, the Florida Keys, and Hawaii are some examples of a ‘true’ tropical climate. Texas, New Mexico, and Arizona also have hot climates but – depending on where you are – it may not have the humidity levels to grow plants like orchids that prefer humid climates. Despite the difference, it is possible to achieve a garden with a tropical ‘feel’ to it even if you’re not in a strictly tropical climate.
Where I live in North Carolina, our growing Zone is 8a. Before 2023, it was 7b. With high humidity and a long growing season, I can grow some tropical-ish plants outside, but that doesn’t include orchids. In comparison, when we were living in South Auckland, NZ (Hardiness Zone 10b), I had Cymbidium orchids growing in the ground. Summers there were not quite as hot as NC but just as humid – possibly even more so. However, winter temperatures rarely got to or dropped below 4°C (39°F), whereas they can get to – and below – 35°F (1-2°C) here in NC. In-ground orchids here would be ‘gonners’ for sure (darn it).
So, what do you do if you live in an area that gets colder than 50°F (10°C), and you want a tropical garden theme? Simple! You get lookalikes that are hardy for your area, and tropical plants with a winter hardiness zone range that includes your area. For people who live in Zones 6 and 7, there are many options. For Zone 6 and colder, it becomes more of a challenge, but it’s still a possibility. An example of lookalikes is shown in the photos below. Hibiscus syriacus ‘Collie Mullens’ is a member of the hibiscus family and hardy to Zone 5. Its lookalike cousin, the tropical hibiscus, won’t survive outside below Zone 10.
A tropical garden is characterized by lush, layered planting with large, bold foliage and blooms in diverse textures and vibrant colors. The objective is to create a sense of jungle-like abundance. Key elements may include water features for sound and light, organic, informal designs, and the use of natural materials like bamboo and stone. Focal points may include large containers with spectacular displays, which, if they happened to include ‘true’ tropical plants, could be relocated into a more suitable environment to over-winter with the help of a hand cart. The goal is to create an immersive, exotic paradise that engages the senses through scent, touch, and sight, even when adapted for climates that are not at all tropical.
I don’t know why, but in my view, a tropical garden needs some garden art. It could be contemporary, religious, whimsical, or homemade. There is just something about all that lush growth that needs the hard, clean lines of an object to bring the whole effect together. An arbor, pool, or patio achieves the same effect.
But what do I mean about look-alike tropicals? Is it really possible?
Let me show you what I mean …
Indian Shot/ Arrowroot (Canna) – winter hardy to Zone 7.
Elephant Ears (Colocasia) – most cultivars winter hardy in Zones 7 and up. ‘Pink China’ hardy in Zone 6.
Daylily (Hemerocallis) – winter hardy from Zone 3.
Scarlet Rosemellow (Hibiscus coccineus ‘Texas Red Star’) – winter hardy Zone 5.
Coral Bells (Heuchera) – winter hardy to Zone 4.
Hosta – winter hardy to Zones 3-4.
… and there are many, many more plants that collectively can produce the same effect as a lush, tropical paradise in an area that is under snow for months of the year. Weird but true!
Article by
Judith Paul
Hi, I'm Judith Paul, with a gardening style best described as “Oooo, there’s a gap over here!” My work history is equally unpredictable (possibly even quirky) and ranges from pulling eel-infested cow carcasses out of creeks to managing multi-million-dollar projects across various industries. I’m a Kiwi (referring to the iconic flightless bird of NZ, not the fruit) who has also lived in Australia. Currently, I run a licensed and inspected plant propagation nursery in North Carolina (USA) when I’m not teaching, writing, or editing.
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