Growing Sweet Chestnut Trees In The UK | Comprehensive Care Guide

growing sweet chestnut trees

We’ve been growing Sweet Chestnut trees for years now, and have lately begun reaping the rewards – as my growing waistline will attest to.

They’re beautiful trees to have around the garden, with their waterfalls of golden catkins overflowing throughout the Summer months enough to brighten the murkiest Welsh ‘Summer’.

They also provide plentiful crops of tasty, nutritious food, and as if that wasn’t enough – their bloom provides a rich source of forage for our local pollinators to boot.

I struggle to find anything not to love about this cracking family of trees.


Fancy diving deeper into the wonderful world of Nut Trees? Check out our Comprehensive Walnut Growing Guide here for more.


Thought to have been brought to the UK by the Romans roughly two millennia ago, the Sweet Chestnut tree – along with its cousin the Horse Chestnut – has been a familiar sight to many of us ever since.

In the grander scheme of the Sweet Chestnut’s life however, this two thousand year jump is likely to be but a blink of an eye. Pollen has been discovered showing that this fabulous tree was present around the Central Europe region more than 10,000 years ago. 

Who knows just how long we Humans, as well as our distant ancestors have been roasting Chestnuts around the fire? 

Anyhoo, cultivation of the Sweet Chestnut tree quickly caught on across mainland Europe, with numerous named cultivars slowly developed in an iterative search for more productive, healthier trees. 

Although much of this legacy would have inevitably been lost to the sands of time, we still have a handful of ancient cultivars available to us today, allowing us to take a step back into our horticultural time-machine if only briefly. 

Much like the Walnut, Sweet Chestnut cultivation didn’t quite take off with the same vigour for us Brits. Our climate – although not awful for growing Sweet Chestnut trees – isn’t quite ideal. They generally prefer warmer climates, with less of those pesky late spring frosts. 

However, with the development of new cultivars along with the gradual warming of our climate, growing Sweet Chestnut trees is definitely something to consider for anybody interested in producing more delicious, healthy, homegrown food.

Throughout this guide we’ll take a look at the various uses of the Sweet Chestnut, the difference between some commonly confused species and of course, how to raise a happy, healthy, productive Sweet Chestnut tree of your own.

Let’s take a look.


Horse vs Sweet : What’s the Difference?

Growing sweet chestnut trees difference between horse and sweet chestnut

Conkers. I’ll perhaps be dating myself here by saying that when I was in school – they were all the rage. 

We had a ‘Secret’ tree, my little conker-mafia. We were sure the nuts from this ancient old thing were imbued with some magical ability to be literally ‘hard-as-nails’. We played by all the rules – Aged them in the airing-cupboard, carefully applied nail polish in one, two, sixteen layers. We worked tirelessly on those little beauties until they were ready for war.

The next day when we went to school, expecting to dominate the yard and officially become the coolest kids known to South-West Wales, the new kid wandered in with his chosen weapon – Dipped in concrete. 

Safe to say we lost that battle. Lesson learned. 


Onto the Actual Information


Anyhoo, ramblings aside. The Sweet & Horse Chestnut trees are, believe it or not, unrelated. Sweet Chestnut trees belong to the genus ‘Castanea’, whereas their horsey counterparts belong to ‘Aesculus’, a family known as ‘Buckeyes’ in the US. 

Horse Chestnuts generally grow more vigorously than Sweet Chestnut trees, growing to around 100ft on average in comparison to Sweet Chestnuts average of around 50ft. The two also differ in lifespan. 

Horse Chestnuts are known to live for up to 400 years, which is an impressive old lifespan if you ask me. Sweet Chestnut trees on the other hand go one step further in the immortality stakes, living up to a staggering 700 years of age. Imagine all the things you could get done. 

I’d finally get a chance to sort out the spare room. What a world that would be.

Finally, onto perhaps the most important difference between this often confused pair of Chestnuts. The Sweet Chestnut is, as many of us know, perfectly edible and frankly delicious. It’s healthy, packed with a wide range of essential nutrients and lower in fat than almost any other nut. 

The Horse Chestnut on the other hand is very much poisonous, and should not be eaten or fed to livestock under any circumstances.

All the more reason to dig out the old nail polish and string and get a game of conkers going, perhaps while snacking on some delicious, definitely not poisonous Sweet Chestnuts. 


Sweet Chestnut Uses

growing sweet chestnut trees

Timber


Timber taken from Sweet Chestnut trees is ideal for a wide range of carpentry & joinery work. It’s commonly referred to as a ‘Poor man’s Oak’, given how similarly the two timbers appear when freshly sawn. Once dried however it isn’t usually difficult to tell the two apart, and there is certainly nothing ‘poor’ about Sweet Chestnut timber.

Strength wise – Sweet Chestnut timber falls a little short of being suitable for true structural work. It is however incredibly durable when used for cladding, light structural applications and both internal and external joinery. 

It has a beautiful dense grain, reminiscent of Ash, and works particularly well as a hardwood coppicing tree.  


Food


Of course for your average joe, the timber value & quality of a Sweet Chestnut tree won’t be of much concern. We’re growing these magnificent trees for their beauty, environmental credentials and of course, most importantly – The barrels full of nuts. 

Sweet Chestnuts have been used as a staple food source for millennia by the time this blog post will find its way out into the wild. Regions of Europe in particular are well known for their reliance on these tasty little nuts as a staple crop, substituted in where grain could not easily be cultivated. 

Their suitability as a grain substitute is owed to their high levels of starchy carbohydrates, and corresponding low levels of both fat & protein. A pretty unique macronutrient profile to find in the wonderful world of nuts. 

Due to their high tannin content, Sweet Chestnuts should always be cooked before eating. They are usually roasted, however can also be boiled, baked or ground into a meal.

Thankfully, Sweet Chestnuts are not only delicious but also form an exceptionally healthy part of a balanced diet, containing unsaturated fats, fibre, calcium, zinc, B Vitamins and more. 

Turns out it’s quite a nutritional punch this little nut packs. 


How to Care for your Sweet Chestnut Tree

growing sweet chestnut trees

As with pretty much any nut tree – Growing Sweet Chestnut trees is a long-term endeavour. Considering you will be caring for a tree which could still be feeding somebody hundreds of years from now (I don’t know about you, but that blows my mind), it pays to take a little time to learn how to set it up for a long, healthy, nut-producing life. 


Planting Your Sweet Chestnut Tree

planting chestnuts

When it comes to growing Sweet Chestnut trees, sunshine is your best friend. Sweet Chestnuts love soaking up those rays, and will grow bigger, healthier and produce far heavier yields if afforded a spot in full sun. They’ll also ideally want deep, fertile, free draining soils, to accommodate their extensive root systems. 

Light, quite sandy soil is best, ideally with a pH balance between 5.5 – 6.5 (Anything over 7 will likely become an issue). Check your intended planting site using a Soil pH Testing Tool before breaking ground, ideally making any required amendments prior to planting. 

Once you’re happy that your site is well suited to growing Sweet Chestnuts, dig a hole around twice as large as your root ball, backfilling once you’ve checked your depth and spread your roots out a little. 

Removing this excess soil only to refill the hole might seem a little strange, but the extra aeration surrounding your Sweet Chestnuts roots will allow them to establish themselves more quickly. 

Amendments can be added to the backfill if you prefer. We like to top-dress most of our amendments, adding only Mycorrhizal Fungi to the backfill. There are different schools of thought on this topic and in my humble opinion, it’s mainly down to personal opinion. 

We highly recommend using Mycorrhizal Fungi if at all possible. Without going into too much depth, it’s made up of a microbial mixture found naturally in all soils which is key to any plant’s ability to take in nutrients necessary for survival. 

Adding powder is thought to kickstart this process, and in our anecdotal experience aids greatly in a tree’s ability to establish itself during those early years. It is cheap, easily found both online and in garden stores, and more than worth the 5 seconds or so it takes to apply. 

Sweet Chestnuts should be staked for the first few years of their lives, especially in areas prone to strong winds. Nothing fancy is needed here, we generally use 2inch round fence posts cut into ~1m lengths. 

Easy, cheap, and most importantly – Helps your Sweet Chestnut tree grow big and strong. Lovely.


Pruning Your Sweet Chestnut Tree

pruning sweet chestnut tree

Pruning of your Sweet Chestnut tree should be carried out during its dormancy period (Autumn – Winter). Carrying this out at any other time of the year is not a good idea, as the resulting bleeding can cause stunted growth along with a higher chance of disease introduction.

All tools should be cleaned thoroughly before beginning your pruning session, as well as in between individual trees. This reduces the chances of disease introduction and is particularly important when pruning Sweet Chestnut trees, given the damage caused by Sweet Chestnut blight. 

You should also ensure that your tools are well sharpened before making any cuts. Blunt tools are prone to tearing or ripping areas of bark, creating the perfect entry-point for any lurking diseases to infect your beloved Sweet Chestnut. 

When you’re ready to get started, begin by pruning out any damaged, diseased or crossed branches. Prune for overall health at this stage, rather than yield potential.

Once this is complete you can move on, pruning now for your desired shape, aiming to achieve sufficient light-penetration across and within your canopy, with a balanced profile to your fruiting limbs. 

Always bear in mind what future growth you are encouraging before making any cuts – Growing Sweet Chestnut trees is at the end of the day, a long-term endeavour, and we should always have our eyes set firmly on the future when working with them. 

Pruning is – in my opinion – one of the most interesting aspects of bringing up any kind of tree. It’s somewhere between an art and a science, with different species, cultivars and individuals all requiring unique treatment. While there are some clear do’s and don’ts, how you prune your tree is in the end down to you, and will differ widely depending on your desired end-goal. 

Since this is such an in depth topic I’d advise you Read Up (Highly Recommended) on the basics before diving in. There are also plenty of videos on youtube with species-specific guidance to add to this. 


Feeding & Watering Your Sweet Chestnut Tree

feeding and watering sweet chestnut tree

Sweet Chestnuts should be given a thick dressing of much in early Spring to set it up for the year ahead. This serves the dual-purpose of both feeding and suppressing any surrounding weeds competing for essential nutrients.

We like to use organic wood chips, sourced from around our ramshackle little farm. We mix this with some well rotted manure and lay a thick dressing, ensuring to leave a doughnut of space directly around the trunk.

Nothing too technical here, just use whatever organic mulch you can get your hands on and ensure it isn’t directly walled up against your Sweet Chestnuts trunk and you’re good to go.

One exception to take note of – Fallen Sweet Chestnut leaves should ideally be removed and not used as mulch, due to some common overwintering pests who’d love nothing more than a human-assisted transport right on top of your beloved Sweet Chestnut trees.

Young Sweet Chestnut trees will need watering throughout any dry spells. Once established however they usually won’t require watering in the UK climate, other than during the most protracted droughts. Heavy, infrequent waterings are the way to go if this is the case, rather than little and often. 


Harvesting Your Sweet Chestnuts

sweet chestnut tree yield

Sweet Chestnuts are predominantly harvested between September – November, yielding between 30-100kg per mature tree (Although harvests of up to 300kg have been recorded). 

With the grey squirrel being so widespread in the UK, you’ll likely need to harvest your Sweet Chestnut before they reach peak-ripeness. Due to their spined hulls Sweet Chestnut trees are a little more resistant to these fluffy-tailed-marauders than other species of nut. 

They’ll of course still try it though, and you’ll need to be vigilant and get a head-start on harvesting to keep them from decimating your crops. 

You can use tools such as the Nut Wizard to make this job a little easier, or alternatively, fitting a tarp or net below your tree and shaking it can work well too – Depending on the size of course!.


Storing Your Sweet Chestnuts


One of the beautiful things about growing Sweet Chestnut trees is the ample yields you’ll be repaid with for your years of loving care. Of course unless you’re looking to eat Sweet Chestnuts for breakfast, lunch and dinner for the next month, or intend to feed your street – You’re going to need a way of storing these delicious nuts for later use. 

As far as nuts go, Sweet Chestnuts don’t store all that well. I suppose it’s the karmic price they pay for being so tasty, what can you do. But fear not, there are a few ways to stretch your supply out for weeks, or even months if needs be. 

Storing Sweet Chestnuts in the fridge works well enough for 2-4 weeks, do keep them in their shells though. If you’re looking for a longer term option, they do hold up quite well in the freezer, staying fresh for around six months or so – but will lose a little of that signature texture in the process.


Common Pests & Diseases 

growing sweet chestnut trees common pests and diseases

Interested in effective, organic methods to reduce pests and disease throughout your garden? Check out our posts on both Companion Planting & Attracting Ladybirds to kick your pest-control into overdrive.


Pests:

  • Oriental Chestnut Gall Wasp – Causes buds & leaves to swell, stunting Sweet Chestnut tree growth over time. Controlled using insecticides, however this is less effective when dealing with large infestations. Infected Sweet Chestnut trees are often destroyed to prevent further spread as a means of control.

Diseases:

  • Sweet Chestnut Blight – A disease native to Asia which has already wiped out huge swathes of Sweet Chestnut across the globe. Enters through damaged bark, resulting in orange cankers and blisters. This is a huge threat to Sweet Chestnut populations everywhere, and is currently controlled mainly through destroying infected trees and quarantining any infected plant material on site. 

Best UK Sweet Chestnut Tree Cultivars

growing sweet chestnut trees best cultivars

Marron De Lyon

Compact variety suitable for smaller gardens. Quick to come into production, producing good yields of delicious dark mahogany nuts.


Marigoule

Very adaptable to different climates & soil-types. Exceptional disease resistance. Begins production around year 5, producing good yields once mature. 


Belle Epine

Adaptable variety across a range of climates & soil-types. Good disease resistance. Ideally suited as a pollinator for heavier yielding varieties. 


Bouche De Betizac

Adaptable variety with very good disease resistance. Requires a pollinator to produce.


Bournette

Early to begin production. Shows good disease resistance along with reliable yields. 


Marlhac

Vigorous grower which requires a pollinator to fruit. Very tasty nuts produced in heavy yields which store particularly well. 


Marsol

Vigorous grower with very good disease resistance. Heavy yields of high quality nuts which store well. Exceptionally well suited to wetter areas of the Uk. 


Maron Goujounac

A terrific pollinator with comparatively small yields. Nuts good quality however despite the smaller yields. 


Maraval

Very high quality nuts produced in good yields. A vigorous grower which shows good disease resistance in the Uk climate. 


Further Reading



And there we have it, a comprehensive overview of everything you’ll need to know before diving head first into growing Sweet Chestnut trees of your very own.

As always I hope this guide has been useful. If you’d like to be kept in the loop of whatever comes next from us here at the EcoGeeks then please feel free to subscribe below.

Have a great day.

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