How to propagate houseplants (aerial roots edition)

Simple propagation for summer 🌱

A while back, J and I were at one of my favourite coffee places. We were sitting in a corner we’d not sat in before, and a gorgeous Rhaphidophora tetrasperma caught my eye. It was tall and bushy and green. The one I have at home is also tall, but more gangly, and while green, it looks just a little sad with its one tall stem with single leaves.

The Rhaphidophora tetrasperma at the Zeeuwse Hemel in Zierikzee (NL)

Since I can never resist getting up-close to other people’s plants, I took a look at it. Why was it so bushy and gorgeous? I soon realised that this plant actually consists of several different plants: each of the stems growing from the pot is a different plant. It also branched out more from the individual stems, and through some clever positioning and tying in, it looked bushy and full.

Some plants, like Pilea peperomioides, Calathea and Alocasia, grow new shoots from their roots. If you own one of these plants and it’s happy, you’ll see new shoots and leaves pop up next in the pot next to the mother plant.

Rhaphidophora tetrasperma doesn’t do that, however. Like Monstera and Epipremnum aureum (devil’s ivy), it doesn’t grow new shoots from its roots. Instead, most of the time they’ll just form really long, stringy stems with leaves on them—that tend to drop from the bottom onwards as time goes on.

If you own one of those plants and want to make it fuller, the easiest thing to do is to add smaller plants of the same species to the pot, which was give a fuller appearance (pruning sometimes helps as well, as I’ll discuss below).

Propagating my Rhaphidophora tetrasperma

The Rhaphidophora tetrasperma is sometimes also called ‘mini-Monstera’, although it’s not a Monstera-species. But like Monstera, it’s a climber that grows aerial roots. These aerial roots play a key role in creating new leaves (new leaves will always appear opposite an aerial roots) and are vital when propagating.

When we got home from our trip, I looked at my Rhaphidophora tetrasperma. I love how it climbs up against the wall in my study, but it’s been butting up against the ceiling and I hadn't figured out a way to support it (our ceiling isn’t all that sturdy).

My Rhaphidophora tetrasperma up against the wall/cupboard in my study

So I did what every good plant parent would do, grabbed my secateurs and cut it down about 20 to 30 centimetres.

Step 1: gather your materials + clean them

Whenever you’re propagating or pruning houseplants, it’s a really good idea to clean the scissors or secateurs you’re using beforehand to prevent transmission of diseases. I clean mine with some alcohol-solution that I got from the pharmacy.

Alcohol, secateurs and paper towel

Step 2: cut your cuttings

When propagating plants with aerial roots, you need to make sure that every cutting you take has at least two of the nubs on it from which aerial roots grow. In water or soil, the cutting will use these to grow new roots from.

This piece of the plant has three little nubs on it from which the aerial roots grow

I cut three one long piece of stem that I divided up into three shorter cuttings. Each had at least three little nubs and a couple of leaves. Plants—including cuttings—need leaves to live, but a cutting with too many leaves will prioritise leaf growth and leaf health over the creation of roots, or at least be slower to do so. I left about three or four leaves on per cutting, as you can see here:

Step 3: put your cuttings in water or soil

You can propagate cuttings in water or soil—my preferred method is water because then I can see what’s actually happening (only for my succulents do I use propagation in soil, also because I worry that otherwise they’d be overwhelmed by the water).

Whether you choose water or soil, put your cuttings in a light place but not in a place where they will get a lot of direct, full sunlight. For me, that means the windows at the back of our house, especially downstairs are perfect, but the windows at the front of the house (which are south-facing) aren’t.

Step 4: wait

It’s now been about five weeks and the cuttings are doing really well! And, what’s more, the plant in the study is also doing well: not only is it creating a leaf at the top near where I pruned it, but also at about two-thirds of the stem—it’s branching out!

Branching out + small roots

I’ll wait a little longer for the roots to get bigger, pinch out the ones that are too near the surface and then I’ll plant the cuttings directly into the pot with the bigger plant, to hopefully create that full look.

It’s been a while and I’d love to know how your houseplants are doing! Which ones are thriving, which ones and struggling and which ones are you propagating this summer? Leave a comment and join the conversation 🌱

Have a really good summer! Until next time—and in the meantime: check out some of my earlier posts to help your plants through the summer: