Protecting a newly planted coastal hedge through its first winter.
Late October marks the start of bare-root planting season on the Dover coast, and the months from November through to March are when new hedging is at its most vulnerable. Roots have not had time to spread beyond the planting trench, chalk drains fast even in winter, and the Channel can send sustained gales that rock unsettled plants in the soil. Most first-winter failures on this stretch of coast are preventable with three practical steps: checking and re-firming frost-lifted plants, mulching the root zone properly, and putting up a temporary windbreak on exposed sites.
Exposure for this job
- Clifftop / Bay (most exposed): frost heave and wind desiccation are at their worst here. Temporary netting windbreaks are not optional on a newly planted clifftop row: without one, the combined effect of Channel salt wind and shallow chalk can kill new plants in a single dry, cold week. Tender species such as griselinia and pittosporum need fleece protection during hard frosts at this exposure level.
- Village / inland (moderate): frost heave still occurs and plants need checking and firming through December and January. A temporary windbreak is worth erecting on the seaward side of a new row facing the Channel, though less critical for planting set into the village itself. Standard mulching and a weekly check through the coldest months is usually sufficient.
- Dover town / sheltered (least exposed): the main risk is frost heave lifting roots in hard cold snaps across the CT16 and CT17 postcode area; wind desiccation is much less of a concern. Check new plantings after any sharp frost and firm in anything that has lifted. Mulching is still worthwhile on the chalk-derived soils under Dover town.
Why the first winter is the highest-risk period
New hedging planted in November or December goes into the ground with no established root system. Bare-root plants are held in position by the soil they were planted into, not by roots that have grown out into the surrounding chalk. Until root growth begins properly in spring, each plant relies entirely on that initial soil contact, and anything that breaks it, whether a hard frost, a gale or simple settling of chalk over a wet December, can leave roots suspended in an air gap rather than in firm contact with moisture.
The compounding factor here is chalk. Free-draining chalk does not re-compact around a lifted root the way clay might during the next rainy day. A root that has been lifted by frost heave on chalk stays lifted until someone firms it back in. This is why regular checking through the first winter is the single most important aftercare task for new hedging on this stretch of coast. For the preparation process that sets new planting up for success before winter arrives, including how to break up a chalk pan and what to work into the planting trench, see our chalk-soil hedge establishment guide.
Frost heave: checking and firming
Frost heave happens when water in the soil freezes and expands, pushing the surface upward and lifting anything embedded in it. On shallow chalk with a thin topsoil layer, as is common at clifftop positions and along the Bay frontage, this can push a newly planted bare-root whip 2 to 4 centimetres above its planting level in a single hard frost.
The Royal Horticultural Society advises checking newly planted trees and shrubs after any sharp frost and firming the soil back around the rootball if plants have been lifted. On the chalk soils at St Margaret's at Cliffe and Kingsdown, treat this as a routine check rather than a reactive one: inspect the new planting after any overnight temperature that drops to minus 3 degrees Celsius or lower, and press firmly down around the base of each plant to re-establish soil contact. Do not wait for several frosts to accumulate. A plant that has been lifted and not firmed back in will desiccate from the base up even in cold weather, because the chalk around an air gap dries out quickly.
The firming technique is straightforward. Press down around the root zone with the heel of a boot on larger plants, or with both hands on smaller whips, working around the full circumference rather than pushing from one side. If the soil surface is frozen solid, wait for a mild day rather than pressing into frozen ground, which can shear roots instead of firming them.
Channel wind and desiccation on newly planted hedging
The second risk at clifftop and Bay level is wind desiccation. Cold drying winds off the Channel can draw moisture from shallow chalk soil faster than new plant roots can replace it, particularly when the root zone has not been well mulched. This is not the same as salt scorch on established hedging: it is a slower process that starves new roots of the moisture they need to extend into the surrounding chalk.
Ashridge Trees, the UK bare-root hedging specialist, advises checking and re-firming newly planted hedge lines on mild winter days because Channel wind loosens recently planted roots even in above-freezing temperatures. The risk is greatest on the seaward-facing side of a new row where there is no natural shelter between the plants and the open sea.
The practical response is a temporary netting windbreak on the weather side of the new planting row. Netting is strongly preferable to a solid barrier at this stage. A solid fence or board creates turbulence on its leeward side and can cause buffeting that dislodges roots, whereas woven windbreak netting reduces wind speed without producing a damaging lee-side eddy. The RHS recommends temporary woven hurdles or netting on stout posts as a short-term measure for exposed sites. Use posts driven at least 45 centimetres into the chalk: lighter temporary fencing pulls out in hard gales above the Bay. The netting only needs to stay in place through the first winter and into early spring, until the plants are showing active new growth and have roots extending beyond the original trench.
Mulching the root zone through winter
A mulch layer insulates the chalk around the root zone against frost and freeze-thaw cycles, and holds what little moisture chalk retains in the cold months. On chalk soils, mulching has an additional benefit: it moderates the temperature swings at the surface of the planting strip, reducing the frequency of frost heave events across the row.
If the new planting was mulched at installation, check the depth now and top up if needed. The target for chalk soils on the Dover coast is 7 to 10 centimetres, firmed around the base of each plant but not piled against the stem itself, which can cause rot at the base over a wet winter. For clifftop positions where light bark chip blows off in a gale, fine horticultural grit or shingle is a more wind-stable choice and weathers naturally with the local chalk and flint. The full planting strip preparation guidance is in our autumn bare-root planting guide.
Tender species: fleece and wrapping at clifftop positions
Most salt-wind-tolerant hedging species on this coast, including hawthorn, blackthorn, yew and holm oak, are fully winter-hardy and need nothing beyond mulching and firming checks. However, several species frequently planted in coastal gardens closer to the village or in sheltered positions become genuinely vulnerable in hard winters when sited on the fully exposed clifftop, and first-winter plants are more susceptible than established ones.
Griselinia littoralis is hardier than its appearance suggests, but first-winter plants at exposed clifftop positions can suffer foliage browning in prolonged hard frosts, particularly when combined with the dry east winds that come in off the Straits in January. A wrap of horticultural fleece around new griselinia during any sustained sub-zero period reduces this risk. Remove the fleece as soon as temperatures recover above freezing: leaving it on during milder spells encourages soft growth that is then more vulnerable when the cold returns.
Pittosporum is more marginal at clifftop level in any winter, and a first-winter plant is at greater risk still. Pot-grown pittosporum planted in autumn at clifftop or Bay positions should be considered for fleece protection through December to February as standard. If you are planting pittosporum for the first time at a fully exposed position, the advice is to get it into the ground early enough in autumn to begin some root establishment before hard frost arrives, which means September or early October at the latest on the Bay-facing slope. For escallonia, which is generally hardier than pittosporum at this exposure level, the first-winter risk is wind desiccation rather than cold as such: see our escallonia hedging guide for the species-specific guidance.
Snow load on new plantings
Snow is less frequent on the south Kent coast than further inland, but when it does settle above the White Cliffs it can cause specific problems for young hedging. On an established formal hedge, a tapered top sheds snow rather than holding it; a newly planted row of whips does not have that profile and will hold snow on its stems in a way that can bend or snap flexible first-year growth.
If snow settles on new planting, shake it off gently as it accumulates rather than waiting for it to build up. The RHS advises clearing snow from branches before the weight causes damage. For small whips, gentle tapping of the support stakes is usually enough to dislodge most snow without touching the plants directly and risking frost damage to cold-hardened growth. This is a lower priority than frost firming and windbreak maintenance, but worth attending to in any prolonged cold spell with snowfall.
Watering in winter on chalk
The standard advice that bare-root hedges need no watering in winter is written for heavier soils that retain moisture through the cold months. Chalk is different. Even in November or December, a week of dry easterly wind at clifftop level can dry the surface chalk to the point where new roots in the planting zone are not getting enough moisture to begin extending. Check soil moisture at 10 to 15 centimetres depth every couple of weeks through the first winter: if it is dry to the touch, water slowly around the base of each plant. This will be infrequent in a wet winter, but in dry Novembers or Decembers, which are not unusual on the Kent coast, it is a real and manageable risk.
The nesting-season transition in late winter
The Wildlife and Countryside Act 1981, section 1, makes it a criminal offence to damage or destroy an active wild bird's nest, with the main nesting season running from 1 March to 31 August. All of the first-winter protection tasks described above, including firming, mulching, windbreak maintenance and removing fleece wrapping, fall well outside that window. However, if you are also planning to cut back any overgrown scrub or hedgerow adjacent to the new planting row as part of a spring tidy-up, that clearance work should be completed before 1 March. The removal of temporary netting stakes and protection materials is not cutting work and does not carry legal risk under section 1, but any cutting of live growth alongside the new planting does.
When to take temporary protection down
Keep temporary windbreak netting and any fleece or hessian wrapping in place until the new plants are showing clear signs of active growth in spring, typically from late March through to mid-April on the Dover coast, depending on species and season. Do not remove protection during a mild spell in February: the most damaging late frosts on the Kent coast often arrive in March or early April, and a plant that has been encouraged into early growth by a warm fortnight is more vulnerable to a late frost than one kept slightly cooler behind netting.
Once the netting is down, the plants will have made their first real root extension into the chalk and can begin managing their own wind exposure. From that point, the guidance in our chalk-soil establishment guide on first-summer watering takes over: the remaining vulnerability in year one shifts from winter cold to summer drought on chalk.
Want advice on first-winter protection for new hedging?
Email hello@stmargaretshedges.co.uk or call 07763 100 477 with your postcode and exposure level. We can advise on whether a temporary windbreak is worth putting up for your specific site, which species at your exposure level need extra protection, and give you a fixed price for new hedging supply and installation including first-winter aftercare recommendations.
Sources: RHS, Preventing winter damage; RHS, monthly trees and shrubs advice for December and January, rhs.org.uk; Ashridge Trees, Year-round hedging care guide; Wildlife and Countryside Act 1981, section 1 (nesting season, 1 March to 31 August). Place names verified against Ordnance Survey gazetteer data: St Margaret's at Cliffe (CT15), St Margaret's Bay (CT15), Kingsdown (CT14), Ringwould (CT14), Dover (CT16/CT17).