If you’re looking for a great culinary mushroom that you don’t have to hunt in the woods for, very few can hold a candle to the king oyster mushroom, Pleurotus eryngii. Although sometimes a bit difficult to find in traditional grocery stores, Pleurotus eryngii can readily be found in Asian markets and high-end gourmet food shops like Whole Foods, if you can stand paying their prices.

Pleurotus Eryngii Essential Features

The king oyster mushroom is typically a rather large mushroom, especially when measured up against its smaller oyster mushroom cousins. Pleurotus eryngii mushrooms look much like an inverted club or trumpet in mid-fanfare, with somewhat flat, unimpressive gills that run down the firm stem. The cap, such as it is, is usually little more than a brown-buff colored growth on the top of the mushroom that is rarely much wider than the stem itself.
Pleurotus eryngii is an oyster mushroom, which is a large species cluster of wood-loving, decomposing or parasitic mushrooms that are, for the most part, edible. Unlike Pleurotus ostreatus, Pleurotus pulmonarius, Pleurotus dryinus and other common wood-rotting oyster mushrooms, Pleurotus eryngii (alas!) is not found in the wild in North America. It is native in Asia, the Middle East, and the Mediterranean coast. However, it is not terribly common in nature. Its Latin name comes from its preferred host, which are largely plants in the Enrygium genus (called the sea holly flower, which is a pretty little thing that reminds me of a cross between an aster and a thistle). Instead, this mushroom has found its niche in growing houses around the world, especially in China and Japan, where its popularity has exploded in the past several decades. Currently, this is the world’s 3rd most popular mushroom, if popularity can be measured by looking at sheer tonnage of shrooms grown annually.
Another feature of Pleurotus eryngii that has always astonished me is its tough fruiting body. Particularly towards the base of the mushroom, fresh king oysters are very firm, sort of like a green eggplant. However, do not allow this to deter you! Once cooked, Pleurotus eryngii becomes supple and tender, much like a scallop, with a slightly sweet and distinctly buttery flavor. One of the first times I ate this mushroom, in fact, I accused the chef of using too much butter in the recipe, and was rather astonished and delighted when the cook retorted that there was no butter whatsoever in the dish I was eating!

Pleurotus eryngii Common Names

A quick note on names: Pleurotus eryngii has a multitude of names under which it is marketed commercially, including the French horn mushroom, the king trumpet mushroom, boletus of the steppes (wat?), Cardoncello (in Italian), and trumpet royale. Rest assured, they’re all the same mushroom; Pleurotus eryngii has gained worldwide acceptance and esteem for its meaty texture, resistance to spoiling, and handsome appearance. As a consequence, different markets have adopted their own names to describe it.
The only common name for Pleurotus eryngii I take issue with is “boletus of the steppes,” for two reasons: first, it does not belong to the genus Boletus or related genera like Tylopilus, Suillus, and Leccinum. All these mushrooms share a sponge-like fertile surface under the cap, which typically consists of tube-like structures that develop and drop spores as the mushroom matures.

Pleurotus eryngii, however, doesn’t have the sponge, it has gills! I suspect it got the name “boletus of the steppes” because large specimens of Pleurotus eryngii often have a sort of bulbous, sturdy stem that looks a bit like a porcini mushroom (Boletus edulis, Boletus rex veris, and other mushrooms in genus Boletus that are marketed under the name “porcini”). My second issue with “boletus of the steppes” is the “steppes” part. This mushroom originated in the Middle East and Mediterranean, as well as some parts of Asia, but nothing I found suggests that these are mountain mushrooms, which makes the “of the steppes” part a bit confusing to me. But I digress, as I am wont to do.

Pleurotus eryngii Cultivation

As stated earlier, Pleurotus eryngii is one of the most widely cultivated mushrooms in the world. Its uniquely durable fruiting body makes it great for mass production and shipping, and the sheer size of the mushrooms is also impressive. However, it is not the easiest candidate for home mushroom cultivation. This is not to say that its impossible to grow Pleurotus eryngii at home, but you will find it much more trying than, say, growing of Pleurotus pulmonarius on whatever straw, wood, or other cellulose-rich material you have lying around.
Pleurotus eryngii can be grown on straw, which is by far the easiest method for growing oyster mushrooms in your home or garden. However, the mycelium of the king oyster mushroom does not produce many fruiting bodies from substrates made from straw, and so most commercial cultivation of Pleurotus eryngii relies on bulk substrates like grain-enriched sawdust. Another feature of the king oyster in culture is that it tends to do much better on sterile, rather than simply pasteurized, growing mediums. Given this, I personally leave the growing of Pleurotus eryngii up to the professionals and buy huge quantities of them whenever I visit my local Asian grocery store!

 Eating Pleurotus eryngii 

Trust me, eating the king oyster mushroom is not a task; its delicate flavor, robust and chewy texture places it near the top of my list for tasty mushrooms, and its neck-and-neck for first place among the cultivated mushrooms with maitake (Grifola frondosa, or hen of the woods if you prefer).
King oyster mushrooms do not soak up much water, so feel free to wash them without fear. They do great when sliced thin and sauteed and then added to soups, sauces (especially creamy sauces!), or baked into casseroles or other such things. Once pan-fried, they remain soft on the inside and firm on the outside even with much additional cooking, so they’re pretty great for dishes you want to do some prep on, and then finish quickly. They don’t need much seasoning on their own, because they already have a quite distinct flavor that holds its own. These mushrooms also make an excellent mushroom vegan bacon that is crunchy, chewy, and smoky!
The only cooking note I can offer for Pleurotus eryngii that might be considered a negative is that the cap (and areas near the cap) are sometimes a lot softer than the firm, almost crunchy base of the stem. Given this difference, the cap-area sometimes does not need as much cooking as the base, and I have to cook the mushroom in two phases: first I hit the sturdy base slices, then add the softer, more pillowy cap and gills after about 4-5 minutes. This is usually not an issue however, unless you’re working with Pleurotus eryngii specimens that are very mature, with a large and prominent cap and gill situation.

Final Thoughts

On the whole, Pleurotus eryngii is an awesome mushroom and it’s well worth taking the time to get acquainted with it. It has lots of vitamins, fiber, and antioxidants on top of its 10-tons-of-awesome flavor, so it’s a healthy shroom as well, and has an admirable culinary versatility that outshines other commercially grown mushroom species.