Corylus Cosford Hazelnut Tree / Cobnut

Cosford Hazelnut Tree / Cobnut

Cosford is a traditional English filbert, hazelnut or cobnut tree grown for sweet edible nuts with a thin shell^{[1] [2]}, excellent flavour, and strong value as a pollinator for other hazelnut varieties. ^{[1] [2]} It produces attractive, elongated filbert-type nuts with a long husk or full beard. The nuts can be eaten green when freshly harvested or dried and stored for winter use. ^[1] Cosford is especially worth considering for flavour, with Kentish Cobnuts Association describing it as one of the best-flavoured varieties. ^[7] Cosford is more of a quality-over-quantity filbert as it is not the heaviest-cropping hazelnut and Trees and Shrubs Online describes the nuts as sweet and medium-sized but borne rather sparingly. ^[5] Sounds like you are not going to be taking on the nut industry from your back garden any time soon.

RHS lists it as Corylus avellana ‘Cosford’, with Cosford Cob, Filbert Cosford, Cosford hazelnut and Cosford cobnut all used as common trade or search names. ^[2]

Cosford also has ornamental value, with bright yellow catkins in winter before the nuts develop later in the year. ^[1] Like other hazels, it can add garden structure, yellow autumn colour, shelter and nuts for wildlife. ^{[8] [9]}

Cosford is not self-fertile, so plant it with a compatible hazelnut, cobnut or filbert nearby if you want reliable nut production. ^[1] The strongest confirmed pollination partners for Cosford are Gunslebert Hazelnut Tree and Halls Giant / Merveille de Bollwiller. ^{[1] [3]}

Cosford is also useful in the other direction because it can pollinate several other hazelnut varieties. RHS lists Cosford as a pollinator for Butler, Gunslebert, Hall’s Giant / Merveille de Bollwiller and Kentish Cob. ^[3] Kentish Cobnuts Association also lists Cosford as a pollinator for Kentish Cob and Merveille de Bollwiller / Hall’s Giant. ^[4] Confusing, we know. Hazel pollination can be a one-way process i.e. just because it is ready to give pollen, doesn't mean it is ready to receive it. This is why hazel pollination can get a bit complicated. Hazels are wind-pollinated, but good nut set still depends on compatible pollen being available at the right time. ^{[2] [3]}

Nearby wild hazel may help with pollination, but named compatible cultivars are the safer choice when planting specifically for nut production.

RHS gives Cosford an ultimate height and spread of around 2.5–4m, usually reached in 5–10 years. ^[2] It can be grown as a natural large shrub or small hazel tree, or kept more controlled with normal cobnut-style pruning. Although it is a smaller tree and therefore more suitable for container growing, as it grows a nut crop, the maintenance requirements are much higher so by all means, give it a go but we suspect good results will be hard to come by.

It can also sit well in a mixed naturalistic planting or informal boundary, although for nut production it is better managed as a productive bush with space and light.

Planting a Cosford Hazelnut Tree

Plant Cosford in full sun or partial shade. For the best nut production, choose a sheltered position with moist but well-drained or well-drained soil. RHS lists chalk, clay, loam and sand as suitable soil types, so Cosford should suit a range of garden soils as long as the site is not waterlogged. ^[2]

Before planting, water the pot well. Dig a generous planting hole, loosen the surrounding soil, and plant the tree at the same depth it was growing in the pot. Firm the soil gently around the roots and water thoroughly after planting.

Keep the tree watered during dry spells while it establishes, especially in the first growing season.

If growing Cosford for nuts, give it enough room to develop and keep a compatible pollination partner nearby. Prune only where needed to remove dead, damaged, crossing or badly placed growth, and to keep the plant open enough for access and air movement.

Like other hazels, Cosford is a fairly tough plant, but for the best nut production it is better planted in a sheltered position rather than an exposed site. It can be kept more controlled with pruning, but for long-term growth and better nut production it is better in the ground than in a container.

Other Interesting Information About Cosford Hazelnut Trees

Cosford is an old English variety. Frank P Matthews says it originated around Ipswich in 1816, while Trees and Shrubs Online describes Cosford / Cosford Cob as an old English selection known by 1829. ^{[1] [5]}

If Frank P Matthews is right, Cosford would have originated around Ipswich in 1816, which puts it in one of the strangest years in modern history. 1816 became known as the “Year Without a Summer”, after the 1815 eruption of Mount Tambora caused major global cooling. Britain was also recovering from the Napoleonic Wars, with post-war economic problems including high food prices, unemployment and unrest. The same miserable summer helped inspire Mary Shelley’s idea for Frankenstein, so Cosford’s early history sits in a year of bad weather, food anxiety, social pressure and accidental Gothic literature.

If it was created, found, discovered, invented or purchased off the ancient version of Amazon in 1829 then the following applies.

By 1829, Cosford belonged to a Britain that was changing fast. The Roman Catholic Relief Act had opened Parliament and public office to Catholics, while the Metropolitan Police Act created London’s first modern police force. The same year, Stephenson’s Rocket helped prove the future of steam railway travel at the Rainhill Trials, and King’s College London was founded by Royal Charter. So when Cosford was already known by 1829, it was not just an old orchard variety; it came from a period of reform, railways, new institutions and a country starting to modernise.

Cosford was already being described to serious fruit growers by 1829. A notice for John Lindley’s Pomological Magazine described “The Cosford Nut” as highly deserving of cultivation, with large oblong nuts, a remarkably thin shell, vigorous growth and upright branches. [11]

A German hazelnut collection records an even earlier paper trail, saying Cosford was first mentioned as Cosford Nut in the Royal Horticultural Society of London’s 1826 Catalogue of Fruits, then described by John Lindley in 1829. That gives Cosford a more solid recorded history than many old nut varieties, which often disappear into vague “traditional variety” wording. [12]

Cosford may take its name from Cosford Hundred in Suffolk, near Ipswich. A Suffolk cobnut note says it was widely planted in East Anglia, Kent and Nottingham, then spread across the English-speaking world as a pollinator. That is useful history because it explains why Cosford is still worth growing today: it was not just kept for its own nuts, but for helping other compatible hazelnuts crop. [13]

By 1915, Cosford had crossed the Atlantic. An American nut-tree catalogue listed it among imported filberts and cobs, describing it as large, oblong, very thin-shelled and often crackable in the fingers. That makes Cosford more than just a local English curiosity; it was a named variety with enough reputation to be sold to nut growers overseas. [14]

Fruit Tree Life Expectancy
Most fruit trees will give you AT LEAST 40 years of fruit. Pears can go to 70. Records of 200 year old trees exist but this is the exception, not the rule.

Do I Need To Stake My Bare Root Fruit Tree?
Most of the time, the answer will be no, especially if under 200cm tall. However our article on Tree Staking should help guide you.

Planting In The Corner Of A Garden
Air and light is reduced in this location which could promote fungus and bacterial issues. Corners of houses and fences can also suffer leeching issues so we advise against it.