Privet hedge trimming in Rochester: the questions we get from almost every front-garden job.

Q. How many times a year does a privet hedge actually need trimming? Mine seems to grow back almost immediately.

A. Two to three times during the growing season is the honest answer, and that surprises a lot of people who expected once-a-year to suffice. Ligustrum ovalifolium, the oval-leaf privet in most Rochester gardens, is one of the faster-growing hedge species, putting on up to 30 centimetres in a good year. If you want it to stay formal and dense rather than leggy, you need a first cut in late May or early June once the spring flush has hardened, a second in late July or early August, and a third light pass in late August if growth has been vigorous. That final cut is the non-negotiable one: trim any later than late August and you push a new flush of soft growth that will not harden before the first frosts, and you spend winter looking at frost-burned shoot tips. If you only do two cuts, make them early June and late July, then leave the hedge to harden through August on its own.

Q. My last contractor said they couldn't touch the privet between March and August because of nesting birds. Is that really the law?

A. The law is real, though it doesn't quite say what you might expect. Section 1 of the Wildlife and Countryside Act 1981 makes it an offence to intentionally damage or destroy an active bird's nest. The nesting season runs roughly 1 March to 31 August, the penalty is an unlimited fine, up to six months in prison, or both, and not checking first leaves you in a weak position to argue the harm was unintended. Privet is a popular nesting site: sparrows, dunnocks, and blackbirds all use dense privet hedges, particularly the mature runs you find on the long-terrace frontages in Borstal, St Margaret's and down towards the Rochester station streets. What a responsible contractor does in that window is a visual check of the whole hedge immediately before cutting. If there is no active nest, a light maintenance trim is legally fine. What we won't do in that window is heavy renovation or a hard reduction back to old wood, because that disturbs too large a volume of growth to be confident we have not missed anything. If you need major work, that conversation normally comes round to January or February.

Q. My privet hedge has lost most of its leaves this winter. I'm worried it has died back from the roots. How do I tell?

A. In most cases this is the plant behaving exactly as it should. Ligustrum ovalifolium is semi-evergreen: in a mild year it holds most of its leaves through winter, but in a cold or exposed garden it can drop a significant portion. Gardens on the northern side of the ridge above Rochester, facing the estuary winds, or in frost pockets at the bottom of sloping plots in Cuxton or Halling, can see privet looking close to bare by February. The test is the stems: scratch the bark lightly with a fingernail or penknife. If the tissue underneath is green and slightly moist, the plant is alive. If it is brown, dry and brittle throughout, that section has died. A living plant that has dropped its leaves for winter will start showing small new buds in April and a full flush by May. The situation that does indicate root stress rather than just cold is if whole sections remain completely static through April and May while the rest of the hedge leafs up. That can point to waterlogged ground over winter, which is worth addressing with drainage or mulching before the following autumn.

Q. The top of my hedge is thick and fast-growing but the bottom third has gone almost bare. The previous owner clearly cut it for years. What went wrong?

A. The same thing goes wrong with most long-tenured privet hedges: it has been trimmed with perfectly vertical sides, year on year, until the top shades out the lower growth completely. The fix is a tapered profile, the base noticeably wider than the top, so light hits the lower face of the hedge. I'd normally aim for about 10 to 15 centimetres of extra width per metre of height. Once you restore the right profile, the lower growth does come back, but give it a full growing season before expecting a visible result. On a lot of the older terrace frontages in Delce and the roads directly behind Rochester High Street, there's a second factor: decades of foot traffic right at the hedge base have compacted the soil hard. In those cases I recommend loosening the surface carefully without cutting roots, then applying a thick bark mulch kept clear of the stems themselves. It improves moisture retention and the hedge responds within a season.

Q. My privet has grown well above fence height and I want to bring it down significantly. Can I cut it hard into old wood without killing it?

A. Yes, and this is one of privet's genuinely useful characteristics compared to the conifers. It regenerates readily from old wood, so a hard reduction in both height and width is workable in a way it simply is not with leylandii. The window for major renovation work is January to mid-February: the plant is dormant and you are still safely inside the legal window before the nesting season opens on 1 March. I normally stage large reductions over two winters rather than doing everything in one go. Take the top and one long side in the first winter, leave the other side and let the plant recover through the growing season, then do the second side the following winter. Hitting everything at once on a severely overgrown hedge risks an uneven recovery and leaves you with a bare skeleton for a year. On the other hand, privet is aggressive when it does come back: in a good growing season after a February cut, you will often see basal shoots within six to eight weeks, and within two full growing seasons a well-staged renovation looks like a properly managed hedge. See our overgrown hedge renovation Q&A for how we approach the staging decisions on different species.

Q. Are privet berries poisonous? I have small children and a dog in the garden.

A. They are toxic, and it is worth being clear about the degree. Privet berries, the small dark clusters that appear on an unclipped hedge in late summer, are mildly toxic to humans and more significantly toxic to dogs, cats and horses. Ingestion in a child causes gastrointestinal upset; in a dog or cat it can cause vomiting, diarrhoea and lethargy, and in larger quantities more serious systemic effects. If a dog eats a significant number, treat it as a call to the vet rather than something to wait on. The practical point for a maintained hedge: a privet that gets two or three formal cuts a year rarely gets the opportunity to flower and set fruit, since the flower buds are removed with the summer growth. The risk is much higher on hedges that have been left uncut for a season or more. The second hazard worth knowing is the sap: privet sap is a skin irritant, and cutting with a powered hedge trimmer creates a fine spray. Gloves are sensible, and long sleeves worthwhile if you are prone to contact dermatitis.