One reason the verdict is still out on mosquito plants is that there are at least two plants that are called by that name. Who said life was easy?
And, in a broader sense, many plants might qualify; tea tree plant horsemint, rosemary, catnip, and even marigolds are reputed to have mosquito repellant properties. So, how you decide? First, let’s look at the two primary candidates for the term.
The first is Pelargonium citrosa, a member of the geranium family. Whatever repellant properties it may have, it is questionable to call it natural. It was genetically engineered to “incorporate” the repellant properties of the citronella plant.
Again, many people extol its virtues, and others insist it does nothing to repel mosquitoes. If you can stand the idea of a genetically engineered plant in your yard (or if you think genetic engineering is a good thing), then it is, at least, a very attractive ornamental. It has serrated gray green leaves, and a strong, pungent “geranium” type scent. At the very least, it looks nice in any landscape setting.
The second type of mosquito plant is agastache cana. Its common name includes Texas hummingbird mint, bubblegum mint, giant hyssop, or giant hummingbird mint. As you might guess, hummingbirds are quite attracted to it.
It is a New Mexico native, also found in parts of Texas. It is, in fact, a member of the mint family and its leaves do have a pungent aroma when crushed. In its native habitat, it is perennial, and is usually hardy in USDA Zones 5a-9a.
It blooms late summer to early fall, so it catches hummingbirds on their annual migration. The long, medium pink flowers reel in butterflies as well.
When the leaves are crushed and rubbed on the skin, it then serves as a natural mosquito repellant. The scent has been described as a cross between bubblegum and camphor (whether that is alluring or repulsive must depend on whether you are a hummingbird or a mosquito.)
As far as mosquito plants go, the only way to know if they work for you is to try them. Since they are attractive plants, little harm can come from at least seeing if they work for you.
It is clear, for both of these plants that simply having them in the landscape will not repel mosquitoes. The leaves of all repellant plants must be crushed to release the aromatic oils, and then rubbed on the skin.
It is easy to get caught up in what science can, or can’t prove. The real question is whether you can find things that let you be comfortable outdoors without playing the lead role in a mosquito feeding frenzy. Just think about those Aborigines in Australia who used tea tree leaves as a remedy long centuries before Westerners even found them. They didn’t care how the leaves worked, only that they did. Now, hundreds of years later, science is validating what they took for granted.
You are the only person who knows what works for you. So, experiment, and decide for yourself.
If you do decide to try either of these mosquito plants, crush them, rub a bit on, and see what happens. As always, try a bit on a small area first to see if you develop a reaction. Otherwise, just enjoy them as a nice landscape touch.