Sweet chestnut (Castanea sativa) is a deciduous tree from the Fagaceae family. It is also known as European chestnut. It is native to Southern Europe, Asia and North Africa. Probably brought to the British Isles by the Romans, the sweet chestnut has naturalised here. The Romans regarded the tree very highly and it is said that armies marched on sweet chestnut porridge. China is now the largest supplier of chestnuts in the world. Very popular in Britain, the seed, which are called 'chestnuts' or 'sweet chestnuts', are gathered in the autumn and either eaten raw or, more commonly, roasted in an open fire or a brazier.
Growing methods
Sow fresh seed immediately either in pots or a seed bed, undercover or outside. Do not let the seed dry out or it will not germinate. Seeds germinate in late winter or early spring. Plant saplings out in the summer or autumn and provide some protection from any harsh winter weather in their first year. Choose a dry sunny spot. Sweet chestnut are very drought tolerant.
The sweet chestnut is a hardy tree that will grow to a height of 35 metres and have a spread of around 15 metres. It is renowned for its ability to grow to an old age. It can be grown in all types of soil, including poor soil, but prefers a well-drained situation. It flowers in July with long yellow catkins and is pollinated by bees. The seeds or 'chestnuts' ripen in October. Trees take 25-30 years from seed to produce edible the chestnuts.
Other uses
The seed can be used as a starch and whitener for fabrics. The leaves and the skins of the seed can be made into a shampoo. The wood is hard, strong and light. It has a variety of uses including fence posts and basketry. It is a good source of fuel and trees can be coppiced. The leaves and bark are a good source of tannins. Sweet chestnut has a variety of herbal medicinal uses. The leaves and bark are anti-inflammatory, astringent, expectorant and tonic. There is a Bach flower remedy associated with the tree. The sweet chestnut attracts wildlife including pollinating insects, micro-moths as well as red squirrels who love to feed on the chestnuts.
Raw edible parts
The seeds or 'chestnuts' are available in the autumn in Britain and are edible raw or cooked. They have a mild, slightly sweet flavour. Make sure they are fully ripe before using. Chestnuts can be found on the ground under the tree after blustery weather. Look for the open greeny/brown spiky burrs. Remove the outer burr but keep the brown leathery inner skin on until right before you want to use them otherwise they will dry out. The brown shells that are glossy and feel heavy are the best. The brown leathery skin can be softened in a bowl of hot water. Removing both husks and skins are a challenge! After removing the leathery brown skin, you will come across the soft inner skin, called the pellicle. This needs to be scraped off because it is quite astringent. Chestnuts are creamy white and crunchy. Traditionally they are baked, toasted or boiled in their leathery skins. Rich in carbohydrates, they can be dried and ground down to be used as a flour. The roasted seed can be used as a coffee substitute (as can many other seeds and roots). A sugar can be extracted from the seed. The seed can be pickled or preserved. It is often made into a stuffing and used at Christmas.
Issues
Don't mistake a horse chestnut tree (Aesculus hippocastanum), which produces 'conkers' which are not edible, for a sweet chestnut tree (Castanea sativa) which produces 'chestnuts'!
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| Sweet chestnut (Castanea sativa) seed. Image: Kostanj |
Growing methods
Sow fresh seed immediately either in pots or a seed bed, undercover or outside. Do not let the seed dry out or it will not germinate. Seeds germinate in late winter or early spring. Plant saplings out in the summer or autumn and provide some protection from any harsh winter weather in their first year. Choose a dry sunny spot. Sweet chestnut are very drought tolerant.
 |
| Sweet chestnut (Castanea sativa) leaves. Image: Karduelis |
The sweet chestnut is a hardy tree that will grow to a height of 35 metres and have a spread of around 15 metres. It is renowned for its ability to grow to an old age. It can be grown in all types of soil, including poor soil, but prefers a well-drained situation. It flowers in July with long yellow catkins and is pollinated by bees. The seeds or 'chestnuts' ripen in October. Trees take 25-30 years from seed to produce edible the chestnuts.
 |
| Sweet chestnut (Castanea sativa) tree in flower |
Other uses
The seed can be used as a starch and whitener for fabrics. The leaves and the skins of the seed can be made into a shampoo. The wood is hard, strong and light. It has a variety of uses including fence posts and basketry. It is a good source of fuel and trees can be coppiced. The leaves and bark are a good source of tannins. Sweet chestnut has a variety of herbal medicinal uses. The leaves and bark are anti-inflammatory, astringent, expectorant and tonic. There is a Bach flower remedy associated with the tree. The sweet chestnut attracts wildlife including pollinating insects, micro-moths as well as red squirrels who love to feed on the chestnuts.
 |
| An ancient coppiced tree in Surrey. Image: D. Simon |
Raw edible parts
The seeds or 'chestnuts' are available in the autumn in Britain and are edible raw or cooked. They have a mild, slightly sweet flavour. Make sure they are fully ripe before using. Chestnuts can be found on the ground under the tree after blustery weather. Look for the open greeny/brown spiky burrs. Remove the outer burr but keep the brown leathery inner skin on until right before you want to use them otherwise they will dry out. The brown shells that are glossy and feel heavy are the best. The brown leathery skin can be softened in a bowl of hot water. Removing both husks and skins are a challenge! After removing the leathery brown skin, you will come across the soft inner skin, called the pellicle. This needs to be scraped off because it is quite astringent. Chestnuts are creamy white and crunchy. Traditionally they are baked, toasted or boiled in their leathery skins. Rich in carbohydrates, they can be dried and ground down to be used as a flour. The roasted seed can be used as a coffee substitute (as can many other seeds and roots). A sugar can be extracted from the seed. The seed can be pickled or preserved. It is often made into a stuffing and used at Christmas.
 |
| Chestnuts hanging on the tree. Image R. Illes |
Issues
Don't mistake a horse chestnut tree (Aesculus hippocastanum), which produces 'conkers' which are not edible, for a sweet chestnut tree (Castanea sativa) which produces 'chestnuts'!
