← All guides · Species & planting · Updated October 2026

The ground matters as much as the species. What each CT14 soil type needs before you plant a new hedge.

Late October is when the bare-root catalogues arrive and most of the planning effort goes into choosing species. That is the right priority, but in fifteen years working the CT14 coast I have seen more new hedges fail from poor ground preparation than from the wrong species choice. On Deal's coastal shingle the problem is organic matter: the ground drains so fast that roots desiccate before they can establish. On the alluvium behind the seafront terraces it is rubble and compacted sub-base from Victorian rebuild work sitting 20 cm below what looks like decent soil. On Kingsdown chalk it is pH and moisture. Get the ground right and a bare-root privet or griselinia will look after itself through its first year. Get it wrong on CT14's fast-draining coastal ground and even the right species choice is not enough.

The table below sets out the five main soil situations I encounter across Deal, Walmer, Kingsdown, Mill Hill and Sholden, with what each position typically needs before planting day. A more detailed discussion of each follows.

Those are the broad categories. Position within a category matters too. A south-facing Walmer terrace garden with a brick wall behind it holds warmth and moisture differently from a north-facing side passage on the same street. The table is a starting point, not a prescription: the best single thing you can do is push a fork down to 40 cm at the planting line before ordering plants and see what you find.

Sandy shingle and first-line seafront positions.

The shingle bank that runs from Kingsdown through Walmer and along the Deal seafront is, from a horticulture standpoint, almost pure drainage material. It holds almost no water and almost no nutrients. A bare-root griselinia or elaeagnus planted directly into unimproved shingle with no further attention will survive a wet autumn and a mild winter, but the first dry spell after bud-break in April will stress it severely. The roots will not have had time to reach beyond the disturbed zone around the planting position, and the shingle around that disturbed zone holds nothing for them.

The practical answer is to work organic matter into the planting trench or individual positions before the plants go in. Not a thin covering: the roots need organic matter at the level they will grow into. I work in roughly two standard barrow-loads (or two buckets) of peat-free compost or well-rotted manure per square metre of planting strip before digging in the individual positions. For a 10-metre single-row hedge at 40 cm spacing that means roughly eight to ten buckets of organic matter incorporated into the trench before planting.

After planting, a 10 cm depth mulch of woodchip or bark along the whole planting strip is the second most important step. On a first-line shingle position the mulch serves two purposes: it reduces moisture loss from the amended planting zone, and it suppresses annual weeds and grass that would otherwise compete directly with the new plants for the small amount of water the organic matter is now holding. Keep the mulch clear of the stems themselves to avoid collar rot in the first winter.

Species choice remains important. Even with well-prepared ground, a privet or a hornbeam on an exposed Walmer Esplanade position will take longer to establish than a griselinia, elaeagnus or tamarisk on the same ground. Soil preparation reduces the cost of the wrong species choice but does not eliminate it. The coastal windbreak guide covers species that are genuinely first-line tolerant.

Coastal alluvium and the terrace back-garden problem.

Deal and Walmer's Victorian and Edwardian terraces sit on coastal alluvium, which on its own is a reasonable growing medium. The problem in practice is what lies below the surface. From about 1900 to the 1970s, broken building material (brick rubble, lime mortar, broken tile, concrete lumps) was commonly used as fill material to bring low-lying back gardens up to level, or simply disposed of in place. On any terrace plot south of Alfred Square or north of Downs Road, I would expect to find brick rubble at 20–40 cm depth on at least part of the plot.

Before planting a new boundary hedge along a terrace back wall, the single most useful thing to do is to push a fork down to 40 cm along the planned planting line and check. If you hit rubble, clear it. You do not need to excavate the whole garden: the planting strip is typically 30–40 cm wide, and clearing a strip of that size to 40 cm depth is a morning's work with a fork and a barrow. What you remove (old mortar, brick fragments, compacted clay sub-fill) will often have a high pH from lime mortar: mixing that soil back into the planting zone is not helpful. Remove it, replace it with the topsoil from the same trench mixed with compost, and then plant into the improved zone.

Old lime-mortar rubble can locally raise pH to 7.5–8.0 in an otherwise neutral alluvium garden. This is rarely a serious problem for the species most commonly used in Deal terrace gardens (privet, laurel, griselinia and privet all tolerate slightly alkaline conditions well), but it is worth knowing if a plant is showing yellowing of new leaves in its first growing season: on alluvium-over-rubble ground that is frequently iron chlorosis caused by alkaline soil locking up iron, rather than a disease or watering problem.

Chalk-influenced ground: Upper Deal and Walmer village.

The alluvium that covers most of the CT14 coastal strip thins out inland: in Upper Deal, along the Sandwich Road corridor, in parts of Walmer village and increasingly as you move toward Ringwould and Kingsdown, you start to encounter shallow alluvium over chalk substrate. The chalk may sit at 30 cm, at 50 cm, or not surface within the rooting zone at all depending on exact location. The key indicator is soil colour: chalk-influenced soil tends to have a pale grey-white cast to the lower profile, and when you dig to 40 cm you may see white chalk fragments or even solid chalk.

Where chalk is within the rooting zone (0–60 cm), pH will typically run between 7.5 and 8.0, sometimes slightly higher. This does not prevent hedges from growing, but it does significantly narrow the species that establish reliably. Yew, hawthorn, blackthorn, privet, holly, field maple and holm oak all handle chalk conditions well and are the obvious choices. Cherry laurel is also tolerant. Griselinia, pittosporum and photinia are less reliable on strongly alkaline chalk soils: they will often show iron chlorosis in the second and third years as the root system reaches the chalk zone.

Ground preparation on chalk-influenced soils is more about organic matter than about pH adjustment. Adding lime or chalk is never needed; adding acidifiers (sulphur chips, ericaceous compost) is rarely worth doing on a hedge planting in a garden context where the chalk profile is extensive: you are fighting the native chemistry on a large scale. The better approach is to choose species that suit the chemistry and to incorporate plenty of peat-free compost to help moisture retention in the shallow, fast-draining chalk profile.

Mill Hill, Sholden and Great Mongeham: heavier ground with variable drainage.

Inland from the immediate coastal strip, the soils around Mill Hill, Sholden, Sutton and Great Mongeham are heavier: more clay content, slower drainage, more prone to waterlogging in a wet winter and to baking hard in summer. This is a different preparation challenge from the coastal shingle. On clay-heavy ground the problem is not lack of moisture retention but lack of drainage and the soil structure that allows roots to penetrate and breathe.

The practical preparation for a heavy ground planting is a fork-over of the planting strip to break up any compacted pan, particularly if the site has been walked on regularly or if there is a layer of compressed soil from where a fence post or old structure stood. If the ground sits in standing water for more than a day or two after heavy rain, some drainage improvement is worth considering before planting: a thin layer of coarse horticultural grit (not builder's sand, which can set) incorporated into the planting positions, or a simple 30 cm drainage run of aggregate in the bottom of the trench, can prevent root die-back in wet winters.

On heavy ground, bare-root planting from November to February is generally preferable to late-season planting in March: the ground is wetter and more workable in winter, roots settle in well during the cold period, and bud-break in spring gives the plant a head start. The species on heavier inland CT14 ground are often more conventional than on the seafront: hawthorn, blackthorn, privet, hornbeam and field maple are all at home here.

Kingsdown clifftop: the hardest preparation challenge on the CT14 coast.

The clifftop and cliff-back gardens above Kingsdown, on the western edge of the Dover to Kingsdown Cliffs SSSI, present the most demanding combination of soil conditions on the whole CT14 coast: very thin soil over chalk and flint, extreme drainage, alkaline pH and unbroken exposure to the south-westerly. An ornamental hedge in this position requires both the right species and the most thorough ground preparation I use anywhere.

I typically work in three to four buckets of peat-free compost or well-rotted manure per planting position here, not the one or two that suffice on most coastal ground. The reason is that there is effectively no native soil moisture reserve: if rain falls it runs off the chalk within hours, and in the dry CT14 summers (which are consistently drier than the UK average) there is no reserve at depth for roots to find. The amended planting position becomes the only moisture reserve the plant has during its first summer, and it needs to be substantial.

Species choices on clifftop Kingsdown ground are strictly limited to chalk-tolerant and wind-hardy plants. Hawthorn, blackthorn, elaeagnus, holm oak and tamarisk are the backbone species. Escallonia, particularly the macrantha type, handles the salt exposure but is less chalk-tolerant than hawthorn or elaeagnus on a very alkaline profile. Griselinia is an unpredictable choice here: it handles the salt well but struggles on shallow chalk.

A temporary windbreak netting on the exposed side during the first winter and spring is worth the effort on a clifftop site. Not a solid windbreak, which increases wind turbulence rather than reducing it, but a permeable netting on the windward side reduces the desiccating effect of the wind on new growth while the root system establishes. Remove it in the second growing season: the hedge will by then be doing its own wind-filtering job.

When you are replacing an old hedge, not planting on bare ground.

If the planting position is an old hedge line where the previous hedge has been removed or died, there are two additional considerations before replanting. The first is replant disease: planting the same or closely related species in soil that has hosted the same species for many years can result in poor establishment because of soil-borne pathogens that built up against the previous species. The practical advice is either to switch species (replace a dead privet line with griselinia or hawthorn, for instance, rather than replanting privet) or to excavate and replace 30 cm of soil from the old root zone before replanting the same species. On most residential CT14 hedges this is straightforward: a half-metre wide trench along the old hedge line, 30 cm deep, with the old soil barrowed out and replaced with topsoil and compost.

The second consideration is root clearance. Old privet, laurel and leylandii roots can sit at a density that prevents new roots from penetrating the soil profile for the first year. Fork out as much of the old root material as you can from the planting trench before filling: this is a slow job, but it pays back in the first year's establishment rate. Holly and yew roots are less of a problem because they decompose more slowly and maintain soil structure rather than creating a compact mass. Leylandii and privet roots are the worst for density and should be cleared as thoroughly as practical.

Timing: prepare in October, plant in November.

The ideal sequence for a new Deal or Walmer boundary hedge is to do the ground preparation in October, as bare-root stock becomes available from mid-October onwards, and to plant in November. Preparing the ground in October means the soil has time to settle around any organic matter you have worked in, and any rubble clearing or trench filling has a few weeks to stabilise before the plants go in. November planting gives the bare-root stock a full winter to establish, with the roots starting to extend before bud-break in spring.

Pot-grown stock can go in later, from November through to March, or even in April on a well-prepared site with reliable watering in place. But bare-root stock has a narrower window: the plants are dormant from mid-October to mid-March, and planting when the ground is frozen or waterlogged does not work. The sweet spot for most CT14 positions is the second half of November, once the first hard frosts have passed but before the winter rains make the ground unworkable on the heavier inland soils.

For a guide to planting technique once the ground is ready, see the bare-root hedge planting guide, and for the care needed in the first two years on CT14's fast-draining ground, the new hedge aftercare guide.

Sources: RHS Advice, “Improving soil structure” and “Planting hedges”; Ashridge Trees, “How to prepare ground for planting hedging”; British Geological Survey, “Geology of the Deal and Walmer 1:50,000 sheet (Sheet 290)”; Wildlife and Countryside Act 1981, section 1 (nesting birds). Checked against current sources.