All About Herbs: Szechuan Pepper (Zanthoxylum)

All About Herbs: Szechuan Pepper (Zanthoxylum)

What is Szechuan Pepper?

At Jekka’s we grow two forms of Szechuan Pepper:

The term Zanthoxylum is known as Sichuan Pepper or, following the old transliteration, Szechwan Pepper or Szechuan Pepper. The latter is what we use at Jekka’s.

Szechuan Pepper is also known as ‘flower pepper’, which is derived from directly translating the Chinese characters or, from the older (botanical) term, it is known as ’prickly ash’. You can also find it referred to by the old name of ‘fagara’.

The Zanthoxylum species is part of the Rutaceae family that contains all the citrus plants. This is also known as the rue family and contains flowering plants that generally have a strong scent. They can be found across much of Asia, North America, and, in fact, warm-temperate and subtropical areas around the world. China, and the Himalayan region in particular, is home to a diversity of Zanthoxylum species. The genus includes some 250 species.

What does a Szechuan Pepper tree look like?

Like the other Zanthoxylum peppers, Szechuan Pepper forms a naturally untidy, deciduous, spiky bush. For the species we grow, the Japanese Szechuan Pepper is the smaller version growing to 2.5m compared to the Chinese Szechuan Pepper that grows to 4m.

Following the common name ‘prickly ash’ the leaves of the Szechuan pepper are similar to those of the ash tree but are covered in small spikes. As with other plants in the Rutaceae family rubbing the leaves will release a smell of spice and citrus (but be careful of the small spikes!).

The leaves emerge in early- to mid-spring, followed quickly by the young flowers that develop through the summer, resembling small elderflower florets. At Jekka’s the onset of the Szechuan Pepper flowers is accompanied by a hum in the air as the bees come out to harvest the nectar.

As the months get warmer, the Szechuan flowers turn into berries and as they ripen, they flip over, hang down and redden. The small red berries of the pepper, approximately 5mm in size, open as they become fully ripe. However, unlike other peppers, it is the seed husk, or pericarps, that you are after for culinary use.

How do you grow Szechuan Pepper?

Szechuan Pepper can be grown from seed or cuttings and we now are able to sell you seed of both the Japanese and Chinese varieties. However, please be aware, you will be a good few year away from harvesting.

At Jekka’s we also have a limited number of plants available to buy. Jekka’s tip when growing Szechuan Pepper plants is to keep them away from any other citrus plants that you may have. This is because they are in the same family (Rutaceae) as limes, oranges and lemons and Szechuan Peppers can carry the canker that attacks citrus trees.

The Szechuan Pepper will be happy planted out and will survive to -20 Deg. C. You can also keep your plant in a container, pruning it to maintain the size you like.

Similar to growing other herbs, ensure you feed regularly during the growing season and, as the plant establishes, it will also benefit from mulching around the base to minimise competition. It's also sensible to wind a tree guard around the base of the young bark to protect it from hungry visitors.

How do you harvest Szechuan Pepper?

Apart from being a wonderful structural plant in the garden, one of the main reasons to grow a Szechuan Pepper is to harvest the pericarps for culinary use. The outer shell is where the flavour, heat and aromatics are held. The seed is usually flavourless but we have recently heard of it being used as well.

Harvesting is best done as soon as the pinky red seed cases begin to open and show their dark seed, which usually occurs as the summer turns to autumn. Pick whole florets and leave them to dry somewhere warm for a day or two.

If the peppercorns are still closed in mid-autumn, pick them and lay them out on a piece of paper indoors. Within a couple of days the heat from the room will dry the outer skins and they'll split to reveal the seeds.

Separate the seeds from the pericarps and store them away from bright sunlight until you are ready to use them.

Cooking with Szechuan Pepper

The pericarps of Szechuan Pepper have a deep citrusy flavour that is followed by a warm heat. This passes into a strangely numbing, almost anaesthetic feeling that Jekka likens to sticking your tongue on a battery. The combination of citrus and numbing feeling is very unusual and is what causes it to be highly sort after for cooking. It is much more an experience than a flavour.

Visitors to Jekka’s Herbetum might have been treated to the taste. You will be guided to split a seed case in two and nibble slowly on a single half at the front of your mouth. The sensation takes time to develop and is very complex, so be patient and do not rush this.

The numbing sensation that sets the tongue and lips tingling and spicy heat are respectively referred to “ma” and “la” in Chinese cuisine. Szechuan Pepper is usually more "ma" than "la", and so is often accompanied by chilli in hotter dishes.

Szechuan Pepper is often used in the form of flavoured salt. It is wonderfully simple to prepare. Toast or dry fry equal amounts of coarse salt and peppercorns together until they just start to smoke. When the mix is cool, use a mortar and pestle or a coffee grinder to reduce it to a coarse powder.

You can use it any time that you might use salt and pepper: to season meat before, during or after cooking. It goes well on fatty meats, try it sprinkled over slow roast belly pork or on a duck breast.

Chinese Five Spice Powder Recipe

Chinese Five Spice Powder is very much at the heart of Szechuan cooking and, as with many things, making your own is much better than anything you can buy. It encompasses all five tastes—sweet, sour, bitter, salty, and umami—and uses five different spices. For the recipe below, we recommend using whole spices that you grind yourself as this has more flavour than using pre-ground spices.

The gentle toasting will bring out the aromatics contained within Szechuan Pepper but it is best to toast and create your powder in relatively small quantities to retain that potent flavour and the sought after “ma” and “la” qualities for longer after grinding.

This is Mark Diacono’s recipe and makes about 1 x 225g jar:

  • 2 star anise or 1½ tbsp ground star anise
  • 1½ tsp fennel seeds
  • 5cm of cinnamon stick or 2 tsp ground cinnamon
  • ½ tsp Szechuan Pepper
  • 6 cloves

Preheat the oven to 140C/Gas 1. Place any of the spices that you are using whole on a baking tray and put them in the oven for 4 minutes, until lightly toasted.

Use a clean coffee grinder or pestle and mortar to reduce the spices to a fine powder. Sieve out any larger particles if you prefer, and store in an airtight jar away from direct sunlight. The spice powder mix should keep for 3 months or so.

Chinese Five Spice goes wonderfully well with chicken and pork as a marinade and as a season during the breading for fried foods. However, nothing quite beats it rubbed into the lightly-oiled skin of a duck before roasting.

Want to know more?

This blog builds on Jekka's previous Herbs of the month blogs: Bay (January), Rosemary (February), Salad Burnet (March), French Tarragon (April), Angelica (May), Alliums (June), Lavender (July), Basil (August) and Mint (September).

For advice on growing and maintaining herbs, check out Jekka's How to Grow Herbs videos and ‘Jekka’s Seasonal Tips’ blog series, which includes what to do in your herb garden in early spring, late spring, summer and autumn & winter. Together they form the basis of Jekka’s guide on how to grow herbs.

Herb plants are available and you can organise a collection from our herb farm in South Gloucestershire or at one of our Open Days or Herb Experiences (see our events calendar). Please see our 'Looking Good List' for availability and use our webform or email your list directly to us (sales@jekkas.com). We no longer offer a general mail order service for our plants but we do offer a limited selection of Jekka's Culinary Herb Boxes.