Weird and Crazed Shiitake: Why are my Mushrooms Cracked?

This spring a lot of new growers have been sending pictures of Shiitake with the accompanying question of "Are these shiitake?". These early Spring shiitake look quite a bit different than what you might have seen on their logs in the summer and fall, in the grocery store, or on the web.

cracked shiitake mushroom cap
spring shiitake mushroom cap
brown mushroom with cracks on cap

Are these Shiitake?

Early spring is the time of the classic "flower donko," an Asian grade of Shiitake that is ideal for drying. Due to cold nights, warm days, and large swaths of rain followed by dry spring winds, the thick cuticle of the mushroom cap stretches and cracks to make room for the swelling succulent tissue underneath and as a result of this, the mushroom gets a crazed, bumpy pattern that looks like big floral buttons.

Preserving Donko Shiitake

These mushrooms take very little time in the food dehydrator to dry and they loose very little size. The problem? If you are selling them as a fresh mushroom, they are very light weight and you have to explain to your customer that they are fairly dry in the fry pan so extra oil or liquid may be necessary to achieve the usual Shiitake texture. They are packed with nutrition and have excellent flavor though!

Any strain of Shiitake can become a flower donko if the conditions are right. The pictures in the top of this blog are, in fact, all West Wind. Most often, cold weather Shiitake strains give us the largest percent of flower donkos because they like to fruit in the early spring. Frequently in cool, prolonged springs, the wide range and warm weather Shiitake will fruit and be subjected to the same cool, windy weather and also end up in the flower donko grade. It's all about the environment!


What is a Donko Shiitake:

A decorative grade of Shiitake commonly seen in the spring that is ideal for drying.

Most often seen with:

Spring Shiitake are some of the most beautiful mushrooms and they are a once-a-year seasonal item. Inoculating your logs with cold weather strains will give you the greatest percent of these jewels because they fruit when the weather provides the cold/warm/wet/dry environment. Unless you are drying them for long term storage, however, you may not want to let the mushrooms get quite so dry and cracked. We have actually spritzed boxes of these Shiitake with water and left them in the cooler with the lid on the box to let them absorb a little moisture. To avoid having to do that, read the tips in our blog post, "Spring Shiitake: Tips for the Best Early Crops", to manage your developing Shiitake so they will become the thick, succulent spring Shiitake, just perfectly moist with a little bit of crazing on the cap for beauty.