Mini-monstera (Rhaphidophora tetrasperma). Photo: greeneryunlimited.co
Yes, it’s being called mini-monstera, but it really isn’t a monstera, that is, a member of the genus Monstera, best known for the Swiss cheese plant (M. deliciosa). It also sold for a few years under the name Philodendron ‘Ginny’, but it’s not a philodendron either.
It’s actually Rhaphidophora tetrasperma, an aroid (member of the Araceae family) like both monsteras and philodendrons, but native to Malaysia and Thailand. (Monsteras and philodendrons are native to the New World tropics.) It’s much more closely related to another common houseplant, the pothos (Epipremnum spp.), which is likewise native to Asia as well as Oceania.
The name Rhapidophora means “needle bearing”, a reference to the needle-shaped crystals of calcium oxalate called raphides that make all plant parts unpalatable and somewhat toxic.
From Shingle-leaf to Pinnate
Like most rhaphidiphoras, R. tetrasperma grows as shingle plant in its youth. It sprouts on the rainforest floor and begins to climb a host tree, bearing small, heart-shaped leaves with no visible petiole that press flat against the bark, each leaf partly covering its neighbor, like a shingle. Eventually, it may sever its ties with the roots below and thus grow as a hemiepiphyte, rooted into tree trunks and branches. It is said to reach up to 16 feet (5 m) tall in the wild, but I’ll bet it can grow much higher than that, although having no jungle to grow it in, that’s something I can’t test myself.
As it grows higher and higher, receiving more and more light, the leaves get larger, eventually producing petioles and growing away from the tree’s bark. As it climbs further and receives even more light, the new leaves start to produce cut edges and fenestrations much like a Swiss cheese plant. Eventually, at least in the wild, they can reach almost 14 inches (35 cm) in length, by which time they are actually pinnate, like a fern. However, the specimens we’re being sold as mini-monsteras are subadults, with just a few cuts and are rarely more than 5 inches (13 cm) long.
It’s unlikely your mini-monstera will ever bloom indoors and if it did, the blossoms wouldn’t be much to look at: a sort of cone-shaped green inflorescence with a greenish spathe.
There is a variegated version, still very expensive. So, buy one, propagate it (so easy to do), sell your surplus plants and pay your mortgage!
Easy to Grow
If this plant is catching on so rapidly, it’s not only because of its unusual and attractive leaves, but also because it’s easy to grow. Just pot it up into any well-drained potting mix (some gardeners use orchid mix, but it also grows perfectly well in commercial houseplant soil) and give it medium to good light with some direct sun, although full sun would be too much. It’s the kind of plant you can grow well back from the window in most rooms. Being so fast-growing, it might need annual repotting.
Water it when the soil is dry to the touch (it doesn’t tolerate prolonged drought) and keep it at room temperatures. It does not appreciate the cold and will only be fully hardy outdoors in truly tropical climates (USDA zones 10b to 12).
Light fertilizing with the fertilizer of your choice during the spring through summer growing season is fine. It’s best not to fertilize in late fall and winter so as to avoid encouraging rapid growth under very low light.
For a rainforest plant, the mini-monstera s surprisingly resistant to dry air, even as low as 30% relative humidity, but still, will do best if you can maintain 50% or more. 60% is even better. It makes an attractive terrarium plant, but only if you prune it to keep its rampant growth under control.
Ah yes, its rampant growth! You need to know about that!
The mini-monstera can be very fast-growing—and rangy!—under good conditions. Left alone, it will produce a single floor to ceiling stem and that’s rarely very attractive. It’s not given to branching on its own, so you’ll have to help it. Cut it back whenever it starts to look too thin, then root the cuttings (they’re a snap to root under high humidity!) and plant them up into the original pot so the plant can fill in. Plus the cutback stem will soon produce a new stem or two. Soon you’ll have a full, attractive pot.
Your mini-monstera will look best trained up some sort of support like a trellis and will even cling on its own to a bark slab, a moss pole and even the wall of your living room thanks to its aerial roots.
It also looks wonderful in hanging baskets, but as the stems trail, the leaves get smaller and smaller and they lose their perforations, leaving it looking like a puny philodendron. To understand why, read Climbing Plants Like to Climb.
Pests and Diseases
The usual roster of houseplant pests can theoretically attack the mini-monstera (spider mites, mealybugs, scale insects, etc.), but in fact, it’s a pretty sturdy plant and not terribly attractive to pests. Rot caused by consistent overwatering or growing in containers with no drainage hole is one of the rare diseases that seem to affect it.
A Bit Poisonous
Like most aroids, this plant is a bit poisonous and certainly chewing it can lead to a painful burning sensation thanks to the raphides mentioned above. This will quickly dissuade the chewer from every attempting that again, but still, it’s best to keep this plant (and all aroids) out of the reach of children and pets.
Where to Find It?
Just a few years ago, this plant was very expensive, but it is so commonly available today its price is dropping fast … or at least it should be. Some boutiques haven’t heard the news and still sell it at outrageous prices, so shop around.
You’ll now find this plant in most garden centers or, if not, take a look online. I mean, is any online houseplant source not selling it? You should have no trouble finding it, either locally or by mail order.
The mini-monstera: more than just a passing fancy, it can be a long-lived and attractive indoor plant, maybe one you’d be interested in trying.