When to Prune a Lady Banks' Rose (Banksia Rose): Right After Bloom, and Why Winter Pruning Means No Flowers

The opposite schedule from a modern rose

Modern roses are cut back hard in winter and flower on the new shoots that follow; those winter and summer pruning steps are on the Rose page. None of that applies here. Lady Banks' rose blooms once a year on wood that grew the previous summer and set buds in fall. Cut it in winter and you remove every one of those buds.

So the pruning season is right after bloom in late spring, finished by midsummer at the latest. Light tidying is still fine into late summer, but from early fall on, leave it alone or you damage the buds. Pruning in winter out of habit and getting no flowers the next spring is the single most common failure with this plant.

How to do the after-bloom pruning

Start as soon as the flowers fade. You have three goals: shorten the flowered shoots so new ones grow, thin crowded and old canes so air moves through, and rein in anything that has outgrown its space. With almost no thorns you can work bare-handed; just use sharp bypass pruners so cuts do not crush.

1. Cut flowered shoots back by half Shorten each side shoot that bloomed to about half its length, judging the overall balance. New growth breaks below the cut and carries next spring's buds.
2. Remove old and weak canes at the base Take out canes three or four years old that flower poorly, anything thinner than a pencil, and canes growing into the center. Let light and air into the middle of the plant.
3. Decide what to do with long new canes Thick new canes shooting from the base can be kept and tied in if you want to extend the plant, or cut at the base if you want to hold its size. If you keep them, lay them horizontal.
4. Feed lightly when done Scatter a pinch of slow-release fertilizer at the base to support the new growth. Use half or less of what you would give a modern rose; more means leaves instead of flowers.

Why a winter cut means no flowers

The flowers form along the nodes of canes that grew and ripened from early summer into fall. Buds set in fall, overwinter on the cane and open all at once in spring. A bare winter cane looks like a stick, but it is fully booked with next spring's flowers. Cut it and those flowers are gone.

Cut the whole plant back hard in winter and it will barely flower the following spring. Worse, the shocked plant throws long new canes in spring, and those will not bloom until the spring after that. One winter pruning costs you close to two years, so in winter, adjust ties and nothing more.

1. If you must cut in winter, keep it minimal Remove only what blocks a path, plus broken or dead canes. Protect the buds on everything else and save the real cleanup for after bloom.
2. Count the buds below your cut If a cane truly has to be shortened, cut just above a plump bud. The buds you leave are the flowers you will get, so count before you cut.

Bringing an overgrown plant back down

A neglected plant that has reached the second floor, or canes that have crossed into the neighbor's yard, are also handled right after bloom. At that time you can remove thick canes at the base without weakening the plant, and the summer growth that follows secures next year's flowers. Do not try to reach the ideal size in one year; renew the old canes over two or three seasons.

1. Replace a third of the old main canes each year Each year, cut the one or two oldest woody main canes near the base and train the strongest new basal canes as their replacements.
2. Saw thick trunks and seal large cuts Trunks past ten years old can be several inches thick. Use a pruning saw, and on large wounds apply a sealant to keep rain from rotting the cut.
3. Stop at midsummer If you are not finished by midsummer, leave the rest for next year after bloom. Cutting into fall out of impatience costs you the flowers on the canes you kept.

Pruning a potted plant is mostly thinning

In a container the plant's size is capped, so pruning becomes less about extending and more about limiting cane count. Keep three to five thick, ripe canes on the obelisk and remove the rest at the base after bloom. If the tips of the kept canes stick well above the support, shorten them by midsummer.

1. Cut flowered canes to the height of the support Shortening a spent cane to just below the top of the obelisk lets the regrowth be wound back on. In a pot, a tidy fit matters more than the cut-by-half rule.
2. Rub out thin basal shoots early Letting every thin shoot from the base grow crowds a pot. If you already have enough main canes, snap new thin ones off at the base as they appear.
3. Keep pruning and repotting in separate seasons Pruning is early summer after bloom; repotting is the dormant season. Remember them as two different jobs so you are not tempted to cut while you repot.

Rooting the prunings

The shoots you remove after bloom make good cuttings. In early summer, once growth has slowed and the wood has firmed slightly, cut 4 to 6 in (10 to 15 cm) pieces, strip the lower leaves, make a slanted cut, soak in water for an hour or two and stick them into moist perlite or a sterile cutting mix. Keep them in bright shade and never let the mix dry; roots form in about a month.

1. Take cuttings from this year's wood Use shoots that grew after bloom and have just firmed, not the tips that carried flowers. Leave the top two or three leaves and cut large ones in half to reduce water loss.
2. No direct sun until rooted Keep the cutting pot in bright shade and the mix evenly moist. Pot the rooted cuttings up in fall or the following spring once roots fill the container.