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A philodendron leaf on its own will sit in water looking healthy for months and never become a plant. Roots and new shoots both come from the node, the slightly swollen band on the stem where a leaf joins and where an aerial root usually emerges. Every trailing type method below is simply a way of persuading a node to root.
The upright self-heading types have their nodes stacked so tightly in a single thick trunk that you cannot take a normal cutting from them. Those are propagated by separating offsets from the base or by air layering the trunk, both covered further down.
| What you have | Method to use | When to do it |
|---|---|---|
| A long bare trailing stem | Cut into node sections and root in soil or water | Late spring to early autumn |
| A trailing plant you want fuller | Root cuttings and plant them back into the same pot | Late spring to midsummer |
| An upright plant with shoots at the base | Separate the offsets with roots attached | Late spring only |
| A tall upright plant with a bare trunk | Air layer below the leaves, then cut | Early to late summer |
Rooting effectively stops below about 68F (20C). Attempted in a cold room, the cut end rots before it can callus, which is why winter cuttings fail so consistently.
Taking a trailing cutting
Choose a healthy vine and cut just below a node with clean, sharp pruners, so the node sits at the bottom of the cutting. Two nodes and two leaves is the ideal size. A long cutting with six leaves loses more water through those leaves than its non-existent roots can replace, and it wilts before it roots.
Strip the lowest leaf so that node is bare, let the cut end dry for an hour, then push it into a free draining mix with the bare node buried about an inch (2 to 3 cm) deep. Keep it warm, bright and out of direct sun, and keep the compost just damp rather than wet.
- Cut below, not above The node must be on the piece you keep. Cutting above a node leaves you with a stem section that has a leaf but no growth point, and it will never do anything.
- Use a clean blade A crushed cut from blunt scissors rots rather than callusing. Wipe the blade with alcohol between plants so you are not moving disease from one to another.
- Keep the humidity up for the first fortnight A clear bag loosely over the pot, or a propagator lid, holds the moisture the leafless cutting cannot draw up. Open it for a few minutes daily so it does not go moldy.
- Test with a gentle tug After two weeks pull very lightly. Resistance means roots have formed. No resistance means wait another week rather than digging it up to look.
Water rooting compared with soil
The same cutting in a jar of water roots a few days faster and lets you watch the whole process, which makes it much easier to judge whether anything is happening. Change the water every three or four days and keep every leaf above the waterline.
| Method | Time to root | Advantage | Drawback |
|---|---|---|---|
| Straight into compost | Three to four weeks | No transplant shock at all | You cannot see progress |
| Jar of water | Two to three weeks | Visible roots, very high success rate | Water roots must adapt to soil later |
| Damp sphagnum moss | Two to three weeks | Roots suit soil from the start | Needs checking so it never dries |
| Perlite kept just damp | Three weeks | Almost never rots | Needs potting up promptly once rooted |
Pot a water rooted cutting up once the roots are two to three inches (5 to 8 cm) long. Left in water for months it stays alive but makes almost no new leaves, and the thick brittle water roots then struggle badly in compost.
Making a thin plant full again
The best use of trailing cuttings is not to make new plants at all, it is to fix the parent. An old heartleaf philodendron with four long bare vines looks poor no matter how well you feed it, because the bareness is permanent: leaves do not regrow from an empty stretch of stem.
Cut every vine back to within four or five inches (10 to 12 cm) of the compost in late spring. The parent branches from the nodes you left. Root the pieces you removed and push three or four of them back into the same pot around the edge, and within one season you have a dense plant instead of a straggling one.
Dividing and layering the upright types
Upright self-heading philodendrons produce shoots from the base as they mature. In late spring, tip the whole plant out and look for a shoot that has its own roots. Separate it with a clean knife, keeping as much of its root as possible, and pot it into a container barely larger than that rootball.
For a tall plant whose trunk has gone bare at the bottom, air layer instead. Wrap a handful of damp sphagnum moss around the trunk just below the lowest leaves, hold it with film and ties, and keep it damp. Roots grow into the moss over six to ten weeks while the top is still supported by the parent. Cut below the root ball and pot the top up, and the stump usually sprouts new shoots as well.
Philodendron sap contains calcium oxalate and irritates skin, eyes and mouths. Wear gloves when cutting, wash your hands afterwards, and keep offcuts away from children and pets.
Why cuttings fail
There are only four common causes and they account for nearly every failure. The piece had no node. It was taken when the room was below 68F (20C). It carried too many large leaves and dried out before it could root. Or it was kept sitting wet rather than merely damp and the cut end rotted.
Check those four before deciding the plant is difficult. Given a node, warmth, one or two leaves and damp rather than soaking compost, a trailing philodendron is among the easiest houseplants there is to root.