Hawthorn vs blackthorn: which native hedge is right for you?

If you’re planning a native hedge in the UK, hawthorn (Crataegus monogyna) and blackthorn (Prunus spinosa) are the two species most likely to be on your shortlist. Both are British natives, both make dense thorny hedges that wildlife loves, and both have been planted as field boundaries on this island for hundreds of years. They look similar enough that people regularly mistake one for the other, and the names get used almost interchangeably in casual conversation.

But they’re not the same plant, and for a gardener choosing what to plant, the differences matter. Hawthorn is the better all-rounder for most domestic hedges; blackthorn has its own strong case in specific situations; and a mix of the two — together with a few other native species — produces the richest hedge of all. This guide will help you decide which to plant, and how.

Hawthorn vs blackthorn at a glance

	Hawthorn (Crataegus monogyna)	Blackthorn (Prunus spinosa)
Common names	Quickthorn, May tree, May	Sloe
Bark	Greyish-brown, becoming fissured	Almost black, very dark
Thorns	Moderate, on shorter side branches	Vicious, long, on most stems
Leaves emerge	Before flowering	After flowering
Flowers	May, white, in clusters	March-April, white, before leaves
Fruit	Red haws, autumn	Blue-black sloes, autumn
Growth rate	30-60cm per year	30-50cm per year
Mature hedge height	1.5-4m	1.5-3m
Suckers?	No	Yes, freely
Best for	Most garden hedges	Stock-proof boundaries, wild corners

If you’re trying to identify which is in your garden right now, the shortcut is the flowering/leafing order. Blackthorn flowers on bare wood in March, before any leaves appear — that’s the dramatic snowy display you see in early spring. Hawthorn waits until May, by which time it’s already in leaf, so the flowers appear amongst foliage rather than against bare branches.

How to tell them apart

A quick field guide for when you’re standing in front of a mystery hedge:

Bark colour. Blackthorn is named for a reason — the bark is genuinely close to black, especially on younger wood. Hawthorn is a much paler, warmer grey-brown.

Thorn character. Both have thorns, but they’re different in feel. Blackthorn thorns are long, straight, and brutally sharp. They project at right angles to the stems and they will draw blood. Hawthorn thorns are shorter, often curved, and tend to sit on the side branches rather than projecting from main stems. If you’ve grabbed it without thinking and it really hurt, it was probably blackthorn.

Leaf shape. Hawthorn leaves are deeply lobed, with three to seven distinct fingers — like a small oak leaf in outline. Blackthorn leaves are simple, oval, with a finely toothed edge.

Fruit in autumn. Red berries (haws) are hawthorn. Blue-black, dusty-bloomed berries the size of small marbles are sloes — that’s blackthorn.

Suckers from the roots. Blackthorn sends up shoots from its root system, sometimes a metre or more from the parent plant. This is part of how it forms thickets. Hawthorn doesn’t do this.

Choosing between them for a new hedge

Identification is one thing — buying decisions are another. For a domestic hedge, the question isn’t which is better in the abstract, it’s which is better for your situation.

Speed and density

Both species establish quickly from bare-root whips. In the first three years there’s not much in it — both will put on 30-60cm of growth a year in good conditions, and both will form a useable hedge within four to five seasons.

The difference shows up later. Hawthorn responds beautifully to annual trimming and grows denser the more you cut it. A mature hawthorn hedge that’s been laid or hard-pruned over the years becomes genuinely impenetrable — there’s a reason it’s the species traditionally used for stock-proof field boundaries.

Blackthorn, meanwhile, achieves density through suckering. Left alone it forms thickets that are even harder to push through than hawthorn — but those suckers will travel, sending shoots up two or three metres from where you originally planted. In a wild corner that’s a feature. In a small garden, it’s a nuisance.

Wildlife value

Both species are extraordinary for wildlife — they’re the foundation of the British countryside hedgerow. The Woodland Trust’s hedge research consistently puts both in the top tier for biodiversity.

For pollinators, blackthorn has the edge in early spring: those March flowers are one of the first abundant nectar sources for emerging bumblebee queens and early hoverflies. By the time hawthorn flowers in May, there’s a lot more competition.

For birds, both produce abundant fruit eaten through autumn and winter. Sloes hang on longer than haws, often persisting into January.

For caterpillars and insects, blackthorn is host to a slightly wider range of moth larvae, including the brown hairstreak butterfly which lays its eggs almost exclusively on blackthorn. If conservation is a major motivator and you have space, blackthorn earns its place specifically for the brown hairstreak.

Flowering and visual interest

This is where blackthorn shines. The March display is genuinely spectacular — clouds of pure white flowers on bare black branches, often the brightest thing in the still-bare landscape. There’s a reason “blackthorn winter” is part of British folk weather vocabulary.

Hawthorn flowers later but for longer, and against green leaves rather than bare wood the effect is softer but more sustained. The “May” of “May tree” is no accident — a flowering hawthorn is the unofficial start of summer in southern Britain.

For autumn interest, hawthorn’s red haws are showier than blackthorn’s matt blue-black sloes — though if you make sloe gin, the sloes have a value haws don’t.

Soil and site

Both species are tough. They cope with most UK soils, including clay and chalk, and tolerate exposure that would kill many ornamental shrubs. Hawthorn copes slightly better with drier conditions; blackthorn does well on heavier, damper ground. Both are fully hardy throughout the UK including the Highlands.

In windy coastal sites, both will work, with blackthorn slightly more salt-tolerant.

Maintenance

Hawthorn is the more biddable plant. It tolerates hard pruning, lays well (in the traditional hedge-laying sense), and stays where you put it. A hawthorn hedge clipped twice a year will hold its line indefinitely.

Blackthorn requires more management. The suckering habit means new shoots will keep appearing alongside and beyond the planting line, and unless you’re going for a wild thicket effect you’ll need to cut these out regularly. For a small garden, this is the main argument against pure blackthorn.

Why a mixed hedge is often the best answer

For most UK gardens, the best native hedge isn’t pure hawthorn or pure blackthorn — it’s a mix. A traditional native hedging mix typically contains 60-70% hawthorn (as the structural backbone), 10-20% blackthorn (for early flowering and density at the base), and the remainder split between species like field maple, hazel, dog rose, and dogwood.

The result outperforms any single-species hedge:

• Continuous flowering from March (blackthorn) through May (hawthorn) into June (dog rose).
• Multiple food sources for birds and insects across the seasons.
• Visual interest year-round — autumn colour from field maple, winter stems from dogwood, spring catkins from hazel.
• Genuine resilience: if one species struggles in your specific conditions, the others compensate.

If wildlife is a primary motivator for the hedge, mixed native is almost always the right call. The standard ratio is widely available pre-mixed for bare-root planting through winter.

Planting and care basics

Both species plant identically and follow the same rules as any bare-root native hedging:

• Plant between November and March while the plants are dormant.
• Three plants per metre in a single row for a standard hedge, or five per metre in a double staggered row for a thick stockproof boundary.
• Cut back hard after planting — by about a third for hawthorn, by half for blackthorn. Counter-intuitive, but this forces low branching and gives you a dense base rather than a hedge with bare ankles.
• Water in well, mulch, and protect from rabbits and deer if either is around.

For full planting and aftercare detail — hole prep, root handling, mulching, first-year care — see our bare-root hedging buyer’s guide. The guide covers everything that applies equally to hawthorn, blackthorn, and any other bare-root native species you plant.

If you’re choosing between a single row and a staggered double row, our single or double row hedge guide walks through the trade-offs for both species.

Common questions

Is blackthorn poisonous? The leaves and seeds (inside the sloes) contain trace amounts of cyanide compounds, as do many plums and cherries. The fruit flesh isn’t harmful — sloes are the basis of sloe gin and sloe jelly. Don’t crunch the stones.

Is hawthorn poisonous? No. The haws are edible (though not particularly nice raw) and have a long history of use in hedgerow recipes. Leaves and flowers are also edible — young hawthorn leaves were called “bread and cheese” by country children for their nutty taste.

Are the thorns dangerous? Both can give you a nasty puncture wound and blackthorn in particular is known for causing infections that don’t heal cleanly — old gardeners call it “blackthorn poisoning”. Wear thick gloves when handling either plant, and clean any deep scratches properly.

Can I plant them next to each other? Yes, in a mixed hedge. A 60:40 hawthorn-to-blackthorn ratio gives the best of both, with hawthorn providing the dense main hedge body and blackthorn adding early colour and base density. Just be aware of blackthorn’s suckering habit if you have a tidy lawn or border close by.

Which makes the better stock-proof hedge? Hawthorn — particularly when laid in the traditional way. It’s the species used in proper field hedging across the UK.

Will deer eat them? Both are browsed by deer when young, but neither is a preferred food. Once established above 1m, browsing pressure drops sharply. New plantings should be protected with guards if deer are present.

Where to buy

We grow both species at the nursery and sell them as bare-root whips through the winter season:

• Hawthorn (Crataegus monogyna) bare-root — multiple sizes from 40-60cm whips up to 90-120cm transplants.
• Blackthorn (Prunus spinosa) bare-root — same size range.
• Native hedging mixes for those wanting a traditional mixed hedge with both species and others.

If you’d like specific advice on what would work best for your site — soil type, exposure, length, what wildlife you’d most like to encourage — we’re happy to talk through it. Drop us an email at info@scotplantsdirect.co.uk or call the nursery during opening hours.

Most native hedges started in winter are putting on visible growth by April and forming a credible screen by their second summer. For a hedge that will be there for fifty years, an afternoon of planting in January is a good investment of time.