How to Propagate Aucuba From Cuttings, Layers and Seed

Why the method you choose decides the sex

Because aucuba carries male and female flowers on separate plants, propagation is not only about getting more plants; it is about getting the sex you want. A cutting is a piece of the parent and will always be the same sex as the plant it came from. A seedling is a new individual and will be male or female at random, and you will not know which until it flowers three or four years later.

That single fact should decide your method. If you want a berrying plant, take a cutting from a female that berries. If you are filling a shaded boundary and want a pollinator in the middle of a group of females, take a cutting from a known male. Only if you are planting a large group and are relaxed about the outcome does seed make sense, and even then it is worth expecting to end up with roughly half males.

The other practical point common to every method: aucuba leaves are large and thick, and a cutting carrying full-sized leaves loses water far faster than a rootless stem can supply. Reducing the leaf area is not optional. Every method below involves cutting leaves down by half, and skipping that step is the most common reason cuttings fail on this plant.

Semi-ripe cuttings in late summer

Semi-ripe means the current season's growth that has firmed 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 highest-strike-rate window for aucuba and the method most people should use.

1. Take shoots four to six inches long Cut healthy non-flowering shoots four to six inches (10 to 15 cm) long, early in the morning when the wood holds the most water. Put them straight into a plastic bag so they do not wilt before you get to the bench.
2. Trim to a node and strip the lower leaves Cut cleanly just below a leaf joint and remove every leaf from the bottom half of the cutting. Roots form most readily at the node, and any leaf buried in the compost will rot and take the cutting with it.
3. Cut the remaining leaves in half Reduce the one or two leaves left to about half their area with scissors, cutting straight across. This is the step that decides whether the cutting survives. A full-sized aucuba leaf on a rootless stem will collapse within a couple of days.
4. Insert into gritty potting mix Use 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, insert to about a third of the cutting's length, and firm gently around it.
5. Keep humid, shaded and around 65F (18C) Cover with a clear bag held off the leaves by canes, or use a propagator. Keep it out of direct sun entirely and the compost just damp. Ventilate for a few minutes every couple of days so mold does not build up.
6. Pot up once roots show at the drainage holes Expect six to twelve weeks. Do not tug at cuttings to test them. When white roots appear at the base of the pot, harden off over a fortnight and pot up individually into standard compost, keeping them shaded.

Hardwood cuttings and layering

Hardwood cuttings are the low-effort route and suit anyone who wants several plants without a propagator. In late autumn or early winter, once the wood is fully firm, cut pencil-thick lengths of the season's growth about eight to ten inches (20 to 25 cm) long, trimming just below a bud at the base and just above one at the top. Remove all but the top pair of leaves and cut those in half. Push them two thirds of their length into a slit trench of gritty soil in a sheltered shaded corner, firm them in, and leave them alone until the following autumn. Success is lower than with semi-ripe cuttings but the effort is close to zero and you can set twenty at a time.

Layering exploits the fact that aucuba branches often lie close to the ground. In spring, choose a low flexible stem, scrape a shallow wound on the underside about a foot (30 cm) back from the tip, peg it into a shallow depression with a wire staple, cover with two or three inches (5 to 8 cm) of soil and put a stone on top to keep it there. Keep that patch damp through the summer. By the following spring it will usually have rooted, at which point you sever it from the parent, leave it in place for another few weeks, then lift and move it.

Air layering does the same thing on an upright stem and suits a tall leggy plant you intend to cut back anyway, because it lets you root the good top before removing it. In late spring, ring away a shallow strip of bark 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 that inside clear plastic taped at both ends. Roots show through the plastic within two to four months. Cut the stem below the ball, pot it up, and the stump left behind reshoots as it would after any hard cut, so you get two plants from one.

Growing from seed

Seed is only available from a female plant that has been pollinated, which brings the male-female question round again. The berries color scarlet in autumn and hang on the shrub through winter, softening by late winter or early spring. Collect them when soft, squash them in a sieve under running water to separate the seed from the pulp, and sow immediately. The pulp contains germination inhibitors, and seed sown with it still attached will sit and do nothing at all.

Sow fresh seed on the surface of damp seed-starting mix, cover with a bare sprinkling of grit or sieved compost, and keep it at around 60 to 68F (16 to 20C) in bright shade. Germination is slow and uneven, typically over one to three months, so do not throw a tray away early; late seedlings often appear long after you have given up on it. Transplant into individual pots once the first true leaves appear and keep the seedlings out of direct sun from the very beginning, since young aucuba scorches even more readily than a mature plant.

Seedlings take four years or more to reach a size worth planting out, and they vary in leaf size, vigor and, of course, sex. That variability is a nuisance if you want a matched pair for either side of a doorway, and an advantage if you are planting a long shaded boundary and want a group that does not look mechanically identical. If you go this route, plan to grow more than you need and select the best after they flower.

Record the date you took each batch, the parent plant and its sex, and the date the first roots appeared. Two seasons of that record tells you which week in your own garden gives the best strike, and it means every plant you raise has a known sex from the day it is potted.