How to water propagate indoor plants (the simple guide for beginners)
Except I wasn't entirely sure what a node was, let alone where to cut.
If your plant is a good candidate for water propagation (most of our indoor houseplants are), then this step-by-step how to guide is for you. One of the most popular indoor plant fams that propagate really well in water are Aroids, that's plants like Pothos, Epipremnum, Philodendron and Monstera, but there are lots more good candidates this method works well for. There are also other ways to propagate, this is just the simplest way to start with that I've found works a treat for most members of my indoor jungle.
Water Propagation Step 1: Know your plant's bits (and find the nodes)
The main planty parts you'll be looking for are the nodes, which I've marked on my Pothos N'Joy below. You can see the nodes are located at each junction where the petiole and leaf grow from the main stem.
You'll sometimes see little nubby aerial roots coming out near nodes also (or in the case of some plants like Monstera, they can be monster aerial roots). Here's my Neon Pothos below, also showing you those nodes and aerial roots. This girl's going to be our guinea pig for today's tutorial on where to cut...
Water Propagation Step 2: Cut below a node
Using this method, I like to have at least two nodes and two leaves on each cutting, but you can propagate with only one node and one leaf. Once you've located a node, it's time to get the snips out. Make sure you're using sharp, clean snips so you don't pass any fungal disease, pests or other diseases between plants.
TOOL TIP: Scissors for propagating plants
The cheap Crew Mini Snips are a great option on a budget, but I have to admit I'm slightly obsessed with my Japanese Hidehisa House Plant Shears and use them any chance I get (that's if your budget allows you to invest in something really special for you and your plants).
PRO TIP: Cut stems on an angle
I cut the stem on a roughly 45 degree angle, but the exact angle doesn't matter, as long as it's not straight. The idea behind cutting the stem on an angle vs straight is to find a balance between disease, water and roots. Cutting straight reduces disease because cuttings seal faster, but cutting on an angle helps increase water absorption and root development. Of course we're putting roots first, that's sort-of the point, so I always cut on an angle, but there's an easy way to also protect from disease when you cut on an angle, coming up in step 4 below.
Where to cut...
When you're ready, simply snip the stem on an angle just below a node, ideally below a node that already includes an aerial root. You can work your way down a stem and get multiple cuttings by repeating this same step below every node, or below every second node, making sure to include leaves.
Here's where you could cut this one, or you could shift down the stem a bit, and cut below one node further down instead to give you two nodes in the water. The key thing is to cut below a node but still keep a few leaves...
Why include an aerial root?
Aerial roots aren't the same as soil roots, but can absorb water and nutrients, so including an aerial root in your cutting will help the cutting survive while those new roots grow.
Water Propagation Step 3: Remove extra leaves
Keep the top leaves on your cutting - the roots need them for enough photosynthesis to fuel that new root growth - but do remove the bottom leaves near the node that's going in the water, so the leaves don't end up rotting in the water.
You also don't want too many leaves on your cutting, as without roots the plants can't support lots of leaves for long. On most indoor plants, the nodes are where the new roots are going to grow from. This should mean you end up with cuttings that look a bit like this, below, after you've trimmed off the leaves by the bottom node...
Water Propagation Step 4: Dip in rooting hormone
This is an extra step you don't have to do, but I definitely recommend it. If you're going to cut off that lovely growth tip you might as well do everything you can to make sure it actually roots not rots!
There are a few rooting hormone pastes, powders and gels on the market. Two of the more popular ones are IBAdex and Clonex. The one I use most often myself is Clonex. It's in gel form. You just dip the bottom 1.5cms of the stem of your fresh cutting in the gel, so it coats the bottom node. Tap off the extra gel, then pop your cutting in water or soil. If you have more than one node on the stem going in the water, dab a bit of rooting gel on those extra nodes also. Clonex is a source of auxins, which trigger growth, but it's also an anti-fungal, so it helps protect from disease.
Water Propagation Step 5: Put in water
Time to bring out one of your gorgeous propagation vases you've had plans for. Although pretty much any vessel will do that keeps leaves out and the stem submerged in water. As much as I love those adorable test tube propagation stations, I don't love the constant need to top up the water. A few times I've realised the water level's dropped too low, too late, and a cutting's dried out. Oops. I prefer a medium sized vessel for my cuttings, where the water level doesn't drop as fast due to evaporation, and roots have extra room to grow.
Whatever size your vessel, a good tip is to put them in an area you go every day, like by the kitchen sink, so you can keep an eye on that water level. Find a spot that's warm and bright. Both help those new roots grow, but warmth is a biggie for new growth (when propagating in cooler temperatures, a heat pad is almost an essential to trigger growth). Avoid direct sunlight as it can burn the leaves.
TOOL TIP: Those little 3ml or 5ml pipettes are fantastic for easy water top-ups for little vessels (and for watering tiny and delicate plants), as well as getting out floaters easily. Great for measuring out your fertiliser too.
Here's one of our Neon Pothos cuttings from earlier, below. Snipped, dipped, in water and ready to get those roots growing. This cutting ended up with 3 nodes and 2 leaves. You can see one node above the water, and two below (I like having 2 nodes in water when I can as it increases the number of roots)...
Water Propagation Step 6: Feed
There are 12 essential nutrients plants need that they can't get from light and water alone. Nitrogen, phosphorus and potassium are the biggies. They encourage plants to put out strong, new roots. Start feeding as soon as you notice the first root growing. There are lots of fertilisers suitable for water propagation. One of the best I've heard of is CCS, which is made by the same company who formulated Clonex. Until CCS is available in NZ though, I'd look for a fertiliser that says it's suitable for hydro, or for cuttings and seedlings. Three that I've used with success are Foliage Pro, Grow and Plant Runner.
Water Propagation Step 7: Change the water
You want to change the water in your propagation vessel at least once a week. You can top it up as needed to keep up with evaporation, but entirely fresh water is a good idea about once a week to replenish oxygen for the roots. That's also the time to add a drop of fertiliser as well to keep those essential nutrients up for healthy, strong roots. Get yourself a 3ml or 5ml pipette to make it easy to add what you need.
Water Propagation Step 8: Remove from water
Once your cutting has some nice healthy water roots underway, it's time to remove them from water, and pot them up in substrate. You can stay growing in hydro, but if you do plan to move to soil or another substrate at some stage, then don't leave them too long in water. Left too long, those delicate water roots have a harder time transitioning to bigger, tougher soil roots, and you could lose your new plant after all your patience.
An ideal time for your cutting to graduate from water to soil, is when the main root reaches around 3cm to 5cms long, or an even better sign, is when the main root starts to branch and send out side roots. Some don't branch for some time, and the main root just gets longer and longer.
Here are a few below, all ready to pot up. You can see how the roots have grown from the nodes on each one. The cutting on the left has started to branch, the roots on the middle cutting have been left a little longer than you'd need to, so definitely ready to pot up, and on the right you can see roots of an ideal length, and roots growing from two nodes on that cutting.
How long does it take for cuttings to root in water?
A few factors come into play with how long it might take before you start to see roots. Some plants produce roots super fast, within a week or two, some take 4 to 6 weeks or longer. Heat and light both help, warmth being a key factor (which is why propagating in winter is more difficult), and a rooting hormone definitely speeds everything up.
You can also add a growth booster to the water like Groconut, or even soak your fresh cutting in Groconut to give it a head start, but until the first root appears, there's no need to fertilise at first. Give your cuttings the ideal conditions, and a little boost from rooting hormone, and you should have roots in no time. Before you know it you'll be admiring your new baby plant, created by you!
Water propagation toolbox
Here's what I keep on hand for propagating in water...
SHEARS: Small-tip, sharp shears like the Crew Mini Snips, Hidehisa Indoor Plant Shears or fine tip Hidehisa Houseplant Shears (my favourite), are ideal.
ROOTING HORMONE: I prefer a gel formula (like Clonex), to a powder formula (like IBAdex), for water propagation. Clonex is a source of the growth hormone auxin, and also an anti-fungal to reduce losing fresh cuttings to rot.
PROP VASE: Almost any small vase or container will do, or you can get a purpose-made propagation vase, use a bud vase, or even a small glass. I prefer see-through vessels to keep an eye on root growth, the water level, and to know when they're ready to be potted up. I also tend to like ones with narrow necks to keep leaves from falling in the water.
GROWTH BOOSTER: If you have the budget, or just really don't want to lose a cutting, Groconut is my favourite growth booster to have on hand (you can use it to boost growth on your established plants too, not just cuttings). It's an organic, natural growth booster that provides the growth hormones auxin, cytokins and gibberellin. You just mix it with water.
FERTILISER: Once the first root appears, add a drop of NPK fertiliser in the water with each weekly water change, like Dyna-Gro Foliage Pro or Grow, or Plant Runner Indoor Plant Food. Water and light alone are not enough for the best start for your new baby.
MINI POTS: In a few weeks when those roots are looking good, mini pots are a must in my books. If you transfer your new baby with its delicate water roots into a huge pot, the chances are much higher it won't be able to access what it needs and won't survive. Keep that first pot small. I like both the Crew Mini and Elho Mini pots myself.
SUBSTRATE: It does vary depending on the plant, combined with what I have on hand, but I used to start my cuttings off in hydromix, or about half potting soil, half perlite. Although I've recently been experimenting with fern fibre with superb results, so that's my current go-to.
PS: You absolutely can go next level and upgrade to a prop box, grow house or grow tank, with humidifer, heat pad and more, but I thought I'd keep it to the basics for now since this is more of a beginner's guide.
You made it! I hope you feel more confident now about giving it a go yourself, or found out a few tips and tricks to help you through the 10 stages of plant parenthood. If this guide helped you, please pay it forward and help give another planty parent the confidence to get propagating too :)