Organic Black King Mushroom Grain Spawn

$29.99

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Our USDA-certified organic black king (Pleurotus spp.) grain spawn features a strain that produces hearty mushrooms with beautiful brown marbled caps and soft stems. When cultivated successfully, you can expect a large harvest of very meaty and delicious mushrooms. Black kings offer the hearty texture of king trumpets, but the growth style of a regular oyster. They prefer cooler temperatures and are prone to drying out or stopping their growth if humidity is not maintained when the mushrooms are still in their early stages. They require high CO2 to achieve delicate, long stems, but can also be fruited like oysters.

Recommended use:

  • Black king grain spawn can be used for indoor production using sawdust-based sterile substrate.
  • Do not use grain spawn for log inoculation.
  • This is not a mushroom grow kit. Black king grain spawn must be combined with a substrate in order to fruit.

Upon receiving your spawn:

Remove it from the shipping box as soon as possible. Then, unfold the top of the bag, making room for air space. It's also important to check and confirm that the filter patch is not obstructed. This will help the organism breathe and continue to thrive!

Scroll down for specifications, growing, and storage guides.

Specifications
  • Weight: Approximately 6 lbs
  • Hydration: Average of 47%
  • Bags: Gusseted 2.2 mil polypropylene
  • Filter: High efficiency .2 micron
  • Inoculation Rates: 6 lb. bag of grain will inoculate between 120-165 lb. sterilized sawdust.
  • Sterilization method: Commercial grade autoclave sterilized
Temp, Humidity & CO2 guide
Temperature 55-70°F  |  13-21°C
Humidity (Phase 1: Primordia) 90-95%
Humidity (Phase 2: Fruitbody) 80-90%
CO2 Sensitivity (Phase 1: Primordia) <800 ppm
CO2 Sensitivity (Phase 2: Fruitbody) <800 ppm

 

  • Primordia -  The earliest recognizable stage of fruitbody development. Also known as “baby mushrooms” or “mushroom pins.”
  • Fruitbody - A fully grown mushroom, the reproductive structure of the organism in which the spores are produced.
  • CO2 sensitivity - When CO2 levels are too high, yields will decrease, stems will become long and stringy, caps will be small, and/or growth will halt.
Indoor cultivation

Black king mushroom grain spawn can be mixed into sterilized hardwood sawdust to create beech substrate blocks.

Note: Grain spawn must be mixed with bulk substrate before you can fruit it. If you are new to growing mushrooms, we recommend purchasing a book on mushroom cultivation.

Recommended reading:

'Growing Gourmet and Medicinal Mushrooms' by Paul Stamets

'Organic Mushroom Farming and Mycoremediation' by Tradd Cotter

Storing

If you don't plan to use immediately, you can refrigerate your spawn for up to 4 months.

Cooking

Black kings have a neutral and savory flavor that lends itself well to many different cuisines and recipes. When thinly sliced, they will sear nicely in a pan. With some grated Parmesan cheese, extra virgin olive oil, and fresh thyme, they make a great topping for pasta dishes.

Ingredients

Our grain spawn is USDA certified organic and made using organic cultures from our own culture bank. It contains a blend of locally sourced, organic, and non-GMO grains and supplements from farms in New England and North America.

Cautions & considerations

If you’re going to consume home-grown mushrooms, make sure to cook your fresh mushrooms thoroughly with heat. If it is your first time eating this species, it is best to start with a small amount to check for allergies, even if cooked.

FAQs
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Frequently Asked Questions

No, grain spawn is not an all-in-one kit and cannot be used to fruit mushrooms out of the bag. Grain spawn must be mixed with bulk substrate before you can fruit it.

Grain spawn can be used in a wide variety of ways including indoor growing, outdoor growing, or to make more grain spawn. (Grain spawn can be used to make plug or sawdust spawn, not just other grain spawn.)

  • Indoors, you can mix grain spawn with bulk substrate to grow in bags, in containers, or to create fruiting cakes.
  • Outdoors, you can mix grain spawn with straw or wood chips to make beds and containers. (Note: Grain spawn can not be used for logs.)
  • A grain-to-grain transfer allows you to extend the life of your grain and create more grain spawn.

Our grain spawn is a proprietary blend that features nutrient-rich organic millet and wheat berries.

Cluster of brown-capped mushrooms with long, light-colored stems against a white background.

Organic by design

Made from organic, locally sourced, non-GMO ingredients.

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