Gadenin日本語Get the appChoosing a method
All three methods work, and they suit different situations. Basal suckers are the fastest and most reliable route to a substantial plant, because you are separating something that already has roots, but they are only available if your plant has produced them. Semi-ripe cuttings are the standard method when you want several plants from one parent, and they are also the way to use the top you removed during a hard spring cut. Seed is the slowest and least predictable, but it is the only method that gives you a large number of plants at once, and it costs nothing if the plant flowers.
One practical point that applies to all three: fatsia leaves are enormous, and a cutting or division carrying full-sized leaves loses water far faster than its roots can supply. Reducing leaf area is not optional. Every method below involves cutting leaves down, and skipping that step is the commonest reason propagation fails on this plant.
| Method | Best season | Time to a usable plant | Success rate |
|---|---|---|---|
| Basal sucker with roots | Spring | One season | Very high |
| Semi-ripe stem cutting | Late summer | Two seasons | Good |
| Stem section from a hard spring cut | Spring | Two seasons | Moderate |
| Air layering | Late spring | One season, rooted on the plant | High |
| Seed from ripe berries | Spring, after the berries blacken | Three to four seasons | Good, but slow |
Semi-ripe cuttings in late summer
Semi-ripe means the current season's growth that has firmed up but has not gone fully woody: it bends without snapping and the bark has started to lose its bright green. In most climates that state arrives in late summer, once the main growth flush has finished. This is the window that gives the highest strike rate.
- Take shoots four to six inches long Cut healthy non-flowering shoots four to six inches (10 to 15 cm) long, taking them early in the morning when the wood is fullest of water. Put them straight into a plastic bag so they do not wilt on the way to the bench.
- Trim to a node and strip the lower leaves Cut cleanly just below a leaf joint and remove all leaves from the bottom half of the cutting. Roots form most readily at the node, and buried leaves rot.
- Cut the remaining leaves in half Reduce the one or two leaves you have left to about half their area with scissors, straight across. This is the step that decides whether the cutting survives. A full-sized fatsia leaf on a rootless cutting will collapse within two days.
- Insert into gritty potting mix Use a mix of equal parts compost and sharp sand or perlite, in pots at least four inches (10 cm) deep. Dip the base in rooting hormone if you have it, then insert to a third of the cutting's length and firm gently.
- Keep humid, shaded and around 65F (18C) Cover with a clear bag held off the leaves by canes, or use a propagator. Keep out of direct sun entirely and keep the compost just damp. Ventilate for a few minutes every couple of days to stop mold.
- Pot up once roots show at the drainage holes Expect six to ten weeks. Resist tugging at cuttings to test them. When white roots appear at the base of the pot, harden off over a fortnight and pot individually into standard compost.
Suckers, division and air layering
A healthy established fatsia throws up shoots from the base, sometimes a few inches from the main clump and sometimes a foot (30 cm) away. These are the easiest new plants you will ever get. In spring, scrape the soil back from the base of a sucker and follow it down until you find where it joins the parent, then cut through that connection with a sharp spade or a knife, keeping as much root as possible on the sucker's side.
Lift the sucker with its root plate intact, cut every leaf back by half to reduce water loss, and either pot it into a container just large enough to hold the roots or plant it straight out in a shaded spot. Water it in well and keep it damp but not wet for the first six weeks. A sucker with a decent root system establishes so fast that it often needs no special care beyond that.
Air layering suits a tall leggy plant you intend to cut back anyway, because it lets you root the good top before you remove it. In late spring, choose a point on a bare stem, cut a shallow ring of bark away about an inch (2.5 cm) wide, dust the wound with rooting hormone, wrap it in a fist-sized ball of damp sphagnum moss, and seal the moss inside clear plastic taped at both ends. Roots show through the plastic in two to four months, at which point you cut the stem off below the ball and pot it up. The stump left behind then shoots as it would after any hard cut, so you get two plants from one.
Growing from seed
The late autumn flowers are followed by clusters of berries that ripen from green through to black by spring. Collect them when they are fully black and soft, squash them in a sieve under running water to separate the seeds from the pulp, and sow immediately. The pulp contains germination inhibitors, and seed sown with it attached will sit and do nothing.
Sow fresh seed on the surface of damp seed-starting mix, cover with a bare sprinkling of grit or sieved compost, and keep at around 60 to 68F (16 to 20C) in bright shade. Germination is usually three to six weeks but is uneven, so do not discard a tray early; late seedlings often appear a full two months after the first ones. Transplant into individual pots once the first true palmate leaf appears, and keep them out of direct sun from the start.
Seedlings take three to four years to look like the plant you took the berries from, and they vary in leaf size and vigor. That variability is a nuisance if you want a matched pair for either side of a doorway, and a genuine advantage if you are planting a shaded boundary and want a group that does not look mechanically identical.
Record the date you took cuttings, the number you set, and the date the first roots appeared. Two seasons of that record tells you exactly which week in your own garden gives the best strike, which is far more useful than any general advice about late summer.