Gadenin日本語Get the appWait until the bracts have faded
Do not cut anything while the plant is still colored. Wait until the bracts have dulled, gone papery at the edges and begun to drop, which is typically two to three months after you got the plant, so somewhere in early to mid spring. From then the plant will start pushing pale new shoots from lower down the stems, and that is your signal that it has come out of its display phase.
Once new growth appears, cut back. Leaving it uncut is the reason most second-year poinsettias look wrong: the old stems keep extending, the plant becomes tall and bare at the base with a few small bracts at the top, and no amount of correct dark treatment will fix the shape.
Make the cut hard
People are far too timid with this cut. The plant regrows vigorously from old wood and a hard cut is what produces the bushy, many-headed shape that carries a good display. Take every stem down to four to six inches (10 to 15 cm) from the compost.
- Cut above a node Find the raised ring on the stem where a leaf was attached and cut a quarter inch (5 mm) above it. New shoots come from the buds just below the cut, so cutting just above a node gives you shoots exactly where you want them.
- Leave three or four nodes on each stem Count the leaf scars up from the base and cut above the third or fourth. That leaves enough buds to break into two or three shoots per stem, which is where the bushiness comes from.
- Use clean sharp pruners Wipe the blades with alcohol before you start. Poinsettia stems are soft and pithy, and a blunt blade crushes rather than cuts, which lets rot into the stub.
- Expect white sap and deal with it Cut stems bleed a milky latex for a minute or two. It irritates skin and stains fabric, so wear gloves, cut over newspaper, and dab the cut ends with a damp cloth once the flow stops. It does not harm the plant.
- Reduce watering for a fortnight A plant with no leaves uses very little water. Keep the compost barely moist until new shoots are an inch long, then go back to normal watering. This is the point where a lot of freshly cut plants get drowned.
Pinch through the summer
The hard spring cut sets the framework. What builds the display is pinching through summer, which doubles the number of shoot tips each time, and every shoot tip is a potential head of bracts.
When a new shoot has made four or five leaves, pinch out the growing tip with your fingernails. Each pinched shoot breaks into two, sometimes three. Repeat on the new shoots when they in turn have four or five leaves. Two rounds of pinching over the summer takes a plant from four stems to twelve or more.
| Stage | When | What to do | Result |
|---|---|---|---|
| Hard cut back | Early to mid spring, once bracts fade | All stems to four to six inches (10 to 15 cm) | Two or three shoots per stem |
| First pinch | Late spring, shoots with four or five leaves | Pinch out each growing tip | Shoot count doubles |
| Second pinch | Midsummer, new shoots with four or five leaves | Pinch out each growing tip again | Doubles again, plant fills out |
| Last possible pinch | Late summer, eight weeks before dark treatment | Final tidy pinch only | Bracts have time to form |
| No pruning at all | Autumn onwards | Leave every tip alone | Each tip carries a head of bracts |
Stop all pinching at least eight weeks before you start the dark treatment. Bracts form on the shoot tips, so a tip pinched in early autumn has nothing left to color.
What not to cut
There are three cuts that cost you the display, and all three are easy to make by accident when you are tidying the plant.
| Do not cut | Why | Do this instead |
|---|---|---|
| Shoot tips in autumn | Bracts form there, a pinched tip stays green | Leave every tip from late summer on |
| Healthy green leaves in winter | They feed the bracts through the display | Remove only yellowed or fallen ones |
| Everything back to the compost | There are no buds below the lowest node | Always leave three or four nodes per stem |
| Stems while in full color | Bleeding and shock while it is displaying | Wait until the bracts fade in spring |
Taking cuttings from the prunings
The stems you remove in the spring cut make good cuttings, and it is a better use for them than the bin. Take pieces three to four inches (8 to 10 cm) long with two or three leaves, cutting just below a node.
Stand the cut ends in tepid water for a few minutes to stop the latex flowing, which otherwise seals the base and prevents rooting. Then dip in rooting hormone, push into moist gritty potting mix, cover with a clear bag to hold humidity, and keep at 70F (21C) in bright indirect light. Expect roots in three to five weeks.
Record the date of the hard cut and the dates of each pinch. Next spring those dates tell you whether you cut early enough to fit two rounds of pinching in, which is the difference between a thin plant and a full one.