In New Zealand, buxus (box) hedges are best trimmed twice a year. The main trim comes once the spring growth has firmed up, usually November to December in Tauranga. The second, lighter trim comes in late summer, around February or March. Choose a dry, overcast day each time. Cutting in humid, damp weather invites box blight, and cutting in hot sun can scorch the fresh cut leaves.

If your buxus needs a hard cut to bring it back into shape, that’s a different job, and it’s done at a different time of year. Here’s how both work.

The two regular trims

Buxus grows in flushes. In spring it pushes out soft, pale-green new shoots. Cut those while they’re still soft and they bruise, brown off and look patchy for weeks. Wait until the new growth has darkened and firmed up, then trim.

First trim: late spring to early summer (November to December). This is the main shaping cut. Take the hedge back to its line, leaving a thin layer of the new growth on so the hedge thickens over time.

Second trim: late summer (February to March). A lighter tidy-up to remove the summer growth and keep the edges crisp through autumn and winter. Don’t leave it much later than March. Growth cut in late autumn doesn’t have time to harden off before winter.

A lot of Tauranga buxus hedges, especially low edging around gardens and paths, look their best with exactly these two cuts a year. Taller or faster-growing hedges sometimes need a third light trim in a warm, wet season. Our hedge trimming in Tauranga page has the timing for other common hedges, like griselinia, pittosporum and photinia.

Pick the right day, not just the right month

The day you cut matters almost as much as the month.

Avoid humid, damp days. Box blight is a fungal disease that spreads through spores and loves warm, still, humid weather. Fresh cuts on a damp day give it an easy way in. Tauranga summers can be very humid, so wait for a drier spell.
Avoid hot, sunny afternoons. Freshly cut buxus has tender leaves exposed for the first time. Strong sun on a hot day can scorch them brown.
An overcast, dry day is ideal. If you can, trim in the morning after any dew has dried, and give the hedge a few dry days afterwards.

How much to cut off

For a regular trim, take off most of the new season’s growth but stop at the previous cut line. Buxus will regrow from old wood, but slowly, and a hedge cut back to bare twigs can look thin for a whole season.

A few habits keep buxus dense and healthy:

Use sharp blades. Blunt shears or hedge trimmers tear the leaves, and torn leaves brown off. Sharp blades leave a clean finish.
Keep the top a little narrower than the base. A slight taper lets light reach the lower leaves, so the hedge stays green all the way to the ground.
Clear the clippings, inside and out. Clippings left on top of or inside the hedge hold moisture and can carry disease. Brush them off and collect what falls underneath.
Clean your tools between hedges. If you have any blight in the garden, wipe the blades with a disinfectant before moving to the next hedge.

Cutting back an overgrown buxus hedge

If a hedge has grown well past where you want it, a light trim won’t fix it. Buxus can be cut back hard, but it’s best done in stages and at the right time.

Do the hard cut in late winter or early spring, before the spring flush starts. The hedge then has the whole growing season to recover. Take it back by about a third at most in one go. If it needs to come back further, do the rest the following year. Expect it to look bare and twiggy for a while; with regular feeding and watering it should fill in over the following months.

A hedge that’s very tall, very long or has gone bare at the base is often easier to hand over. Reducing a hedge in stages, so it recovers properly, is a routine part of hedge trimming and pruning.

Box blight: what to look for

Box blight has been in New Zealand since the late 1990s, and it thrives in humid places like the Bay of Plenty. It’s worth knowing the signs so you can act early.

Brown or straw-coloured patches, often starting on the top or sides of the hedge.
Dark spots on the leaves and thin black streaks on the stems.
Leaves dropping, leaving bare patches inside the hedge.

If you see these, cut out and bin the affected growth (don’t compost it), clear fallen leaves from under the hedge, and disinfect your tools. Thinning a very dense hedge slightly improves air flow, which makes it harder for the disease to take hold. A garden centre can advise on treatments. Sadly, a badly infected hedge sometimes has to be replaced, and many people choose a different plant such as corokia or teucrium rather than replanting buxus in the same spot.

Quick answers

Can I trim buxus in winter? Light tidying is fine, but it’s not the best time for a full trim. Winter is better used for a hard cut-back on an overgrown hedge, just before spring growth starts.

Why has my buxus gone yellow or brown after trimming? The most common causes are cutting soft new growth, cutting on a hot sunny day (scorch), or blunt blades tearing the leaves. If the brown spreads, check for box blight.

How often should buxus be trimmed? Twice a year suits most buxus hedges in Tauranga: once in late spring to early summer, and once in late summer.

How much does hedge trimming cost? It depends on the length, height and access. You’ll find starting prices on our prices page, and we give a fixed price before we start.

When to prune buxus hedges in NZ: a Tauranga guide