Gadenin日本語Get the appWhy propagation is routine maintenance here
A pink is not a long-lived plant, and it is not meant to be treated as one. Growth spreads outward from the center each year while the older stems in the middle turn woody, lose their leaves and stop producing flowers. By the third or fourth summer you are looking at a ring of green with a bare, twiggy middle, and no amount of cutting back will reverse it, because the woody center has no dormant buds left to break from.
The way experienced growers keep the same plants for decades is by continually replacing them. Cuttings taken in summer root easily, grow into full plants by the following season, and are genetically identical to the parent, which matters enormously with pinks because scent varies so much from plant to plant. Once you accept the three-to-four-year cycle and take a few cuttings each summer as a matter of routine, you never lose a plant you value.
Summer is the right season because the current year's shoots are then firm at the base but still soft at the tip, which is the state that roots quickest. Spring cuttings are too soft and rot; autumn ones are too hard and sit without rooting.
Taking cuttings the traditional way
The classic method for pinks does not use a knife at all. A non-flowering side shoot is held near its base and pulled sharply, so it comes away cleanly at a leaf joint, leaving a small heel. The pulled cutting is often called a piping. It works because the joint is where root initials sit, and because the pull leaves a clean break rather than a crushed cut surface that invites rot.
Choose shoots that are four to five inches (10 to 13 cm) long, firm at the base, and carrying no flower bud. Anything with a bud on it will try to flower instead of rooting. Take more than you need, since some will fail, and take them in the cool of the morning while the plant is fully turgid rather than in the afternoon heat.
Root them in a very free-draining mix, half and half potting mix and sharp sand or perlite, in small pots or a tray. Rooting hormone is not required and makes little difference, though it does no harm. Expect roots in three to five weeks at around 65F (18C), signaled by resistance when you tug gently on the cutting and by new growth at the tip.
- Pick non-flowering shoots Look for side shoots four to five inches (10 to 13 cm) long with firm bases and no flower bud. Shoots from the outer, healthy part of the mat root far better than anything from the woody center.
- Pull, do not cut Hold the shoot just above a leaf joint and pull sharply downward so it separates at the node. You should be left with a clean break and a small heel at the base.
- Strip the lower leaves Remove the leaves from the bottom third of the cutting so no foliage will sit below the compost surface. Buried leaves rot and take the cutting with them.
- Insert into gritty mix Push each cutting about an inch (2.5 cm) into a half-and-half mix of compost and sharp sand, firm gently, and space them so leaves do not touch. Water once and let the surface drain.
- Keep bright, shaded and barely moist Stand them out of direct sun in bright light at around 65F (18C). Do not cover them tightly; pinks rot under a sealed propagator lid. Mist occasionally rather than watering heavily.
- Pot up once rooted After three to five weeks, tug gently. Resistance means roots. Pot each rooted cutting into its own small pot of gritty potting mix and grow it on in the open, out of the hottest sun.
Layering, which the plant half does for you
Pinks root along stems that lie against the ground, and on an established mat you will often find shoots that have already done so without any help. Lift the edge of a clump and look: a stem with roots coming from a node can be cut free with a sharp knife, potted up, and grown on exactly like a rooted cutting. This costs nothing and has the highest success rate of any method, since the piece is already rooted before it is separated.
You can also do it deliberately. In summer, choose a long non-flowering stem, nick the underside shallowly at a leaf joint, peg it down against gritty soil with a piece of wire, and leave it. Roots form at the nick within six to eight weeks. Sever it from the parent once you can see new growth at the tip, wait another two weeks, then lift it with a trowel and pot it or move it to its final place.
Layering is the safest option when a clump is precious and you are nervous about cuttings, because the piece stays attached to the parent and keeps being supplied with water while it roots. The drawback is that you get far fewer plants than from a batch of cuttings.
| Method | When to do it | Time to a usable plant | Notes |
|---|---|---|---|
| Pulled cuttings | Summer, after the main flush | Three to five weeks to root, planted out the same season | Best for numbers; identical to the parent including scent |
| Layering | Summer, on long non-flowering stems | Six to eight weeks to root, lifted a fortnight after severing | Highest success rate, but only a few plants per clump |
| Self-layered pieces | Any time you find them | Immediate, already rooted | Free plants; check the edge of every mat each spring |
| Division | Early autumn or early spring | One season to make a full plant | Only works on younger clumps with green growth throughout |
| Seed | Spring under cover | Flowers the following year | Seedlings vary; scent is often lost, so not for keeping a good plant |
Division and seed, and their limits
Division works only while a clump is still young enough to be green all the way through. Lift it in early autumn or early spring, pull it apart into pieces that each carry both leafy shoots and roots, discard anything woody, and replant the pieces at their original depth on gritty soil. On a four-year-old plant there is usually too little live tissue in the middle for this to give a worthwhile piece, which is why cuttings are the standard route.
Seed is a different proposition altogether. It is easy and it gives you plenty of plants, but the seedlings will not match the parent. Color, form and above all scent segregate, and a good proportion of the offspring from a strongly fragrant plant will have little or no fragrance. Grow from seed when you want quantity or want to see what turns up; use cuttings when you want to keep something specific.
Whichever route you take, plant the new stock somewhere fresh rather than back into the exact spot the old clump occupied. Soil that has carried a declining, rust-prone plant for four years is not the best start for its replacement, and rotating the position by a couple of feet costs nothing.
Do not let new cuttings or divisions sit under organic mulch over their first winter. Young plants are more vulnerable to crown rot than established ones, so keep grit around them and the center clear.
What to record so the cycle keeps running
Note the date each clump was planted and the date each batch of cuttings was taken and struck. The planting date tells you which clump is due for replacement this summer, which is otherwise guesswork among a group of mats that all look similar. The cutting date, paired with the date roots appeared, tells you how long rooting actually takes in your conditions so you can judge when to pot on rather than disturbing them too early.
Record the parent plant for every batch as well, including whether it was strongly scented. A tray of rooted cuttings with no record of where they came from is a tray of anonymous pinks, and by the time they flower you will have forgotten. Marking the position of each new plant when you set it out completes the loop, so in three years' time you know exactly which mats are the young ones and which need replacing.