Gadenin日本語Get the appA node is not optional
New roots and, crucially, new shoots come from the node, the slightly swollen point on the stem where a pair of leaves joins. A hoya leaf pushed into compost on its own will root and can sit there looking alive for years, but with no node there is no growth point and it will never produce a stem.
So every cutting needs at least one node, and two or three is better. A cutting with more nodes has more chances to shoot and establishes into a bushy plant faster than a single-node piece.
| Material | Roots? | Grows into a plant? |
|---|---|---|
| Tip with two or three nodes and leaves | Yes, readily | Yes. The method to use |
| Bare mid-stem piece with two nodes | Yes, more slowly | Yes, once it shoots |
| Single leaf with no node | Yes | No. It stays a rooted leaf forever |
| Long leafless runner, cut into sections | Slowly | Yes if each piece has a node, but expect losses |
Take cuttings from stems that have hardened slightly rather than from the softest new tip. A very soft tip rots at the cut before it roots.
Timing and conditions
Hoya cuttings root on warmth. Below about 68F (20C) the cut sits there and rots instead of callusing, which is why cuttings taken in the cool half of the year fail so consistently. Late spring through to the end of summer is the window, and the warmer the better within reason.
| Season | Take cuttings? | Rooting time |
|---|---|---|
| Late spring | Best time | Three to five weeks |
| Summer | Very good | Two to four weeks |
| Early autumn | Only if the room stays warm | Five to eight weeks |
| Late autumn to early spring | No | It will rot rather than root |
Taking and rooting the cutting
The method is simple and the failures nearly always come from one of three things: no node, a cold room, or compost kept wet rather than just damp.
- Cut below a node Use clean sharp pruners and cut half an inch (1 cm) below a node, so the node sits at the bottom of the cutting. Take a piece four to six inches (10 to 15 cm) long with two or three nodes.
- Strip the lowest leaves Remove the leaves from the bottom node so they are not buried. Leave two to four leaves at the top. A cutting carrying too much leaf loses more water than its non-existent roots can replace.
- Let the cut dry Stand the cutting in a dry shady spot for an hour or two, or overnight for a thick stem, until the cut end is dry to the touch. Hoya stems bleed a milky sap and pushing a wet cut straight into compost invites rot.
- Insert it into a gritty mix Use half perlite and half fine bark or a free draining seed mix, and bury the lowest node. Water once, then keep the mix barely damp. Somewhere warm, bright and out of direct sun.
- Wait for a shoot, not a root Do not tug at it. Roots appear in two to five weeks but the sign that matters is a new shoot from a node. Until then, resist the urge to check, because every disturbance sets it back.
Hoya sap is milky and irritates skin and eyes. Wash your hands after cutting and keep the sap away from your face.
Water rooting and layering
Two alternatives are worth knowing. Rooting in water lets you watch progress, which makes it the easiest method to judge, but water roots are structurally different from soil roots and a cutting left in the jar for months struggles badly when you finally pot it. Move it into compost as soon as the roots are one to two inches (3 to 5 cm) long.
Layering is the most reliable of all and barely disturbs the parent. Pin a length of trailing stem down onto the surface of a second pot of compost, so a node is in contact with it, and leave it attached to the parent plant. It roots at that node while the parent keeps feeding it, and you cut it free six to ten weeks later.
| Method | Time to a rooted plant | Reliability | Best for |
|---|---|---|---|
| Cutting in a gritty mix | Four to eight weeks | Good | Making several plants at once |
| Rooting in water | Two to four weeks to roots | Good, but pot it up early | Watching what is happening |
| Layering into a second pot | Six to ten weeks | Very high | One reliable plant with no risk |
The wait for flowers, and what to record
A cutting takes two to three years from rooting to its first flowers, and sometimes longer. Nothing hurries that. The one thing you can do to shorten it is to let the young plant run: allow the stems to extend and mature rather than trimming it into a neat ball, because the flower spurs form on that mature growth.
Put three or four cuttings into one pot rather than one each. A single cutting makes a thin, sparse plant that takes years to look like anything, whereas a pot of three fills out in one season and they all flower at the same time later on.
Label each pot with the date you took the cutting and the month it first shot. Compare across a couple of years and you will find the fortnight in your own house when hoya cuttings root fastest, which is more useful than any general advice.