Grain Spawn

  • Can I fruit my mushrooms off of grain spawn?

    Unfortunately, mushrooms don’t fruit well off of just grain. Though some mushrooms may eventually grow off grain spawn, the yields will be minuscule. It's much better to use it to inoculate other substrates. Most mushrooms prefer to fruit off of grain mixed with substrates like manure, hardwood,...

  • Can I use some grain spawn and save some for later?

    Best practice is to plan on using all of your grain spawn bag once the bag is opened. Attempting to store it for prolonged use after it has been opened will most likely result in contamination.

  • How do I use grain spawn?

    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 t...

  • How is your grain sterilized before inoculation?

    All of our grain spawn is sterilized in a commercial-grade autoclave. We also verify sterility using biological indicators and temperature sensors.

  • How much substrate can one 6lb bag of grain spawn inoculate?

    One 6 lb. bag of grain will inoculate between 120-165 lb. sterilized sawdust, and 100-130 lb. pasteurized straw.

  • Is grain spawn the same as an all-in-one kit?

    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. If you would like to purchase a ready-to-grow kit, try starting with a Spray & Grow Kit or Fruiting Block Kit.

  • Is my mushroom spawn moldy? What are the white and yellow substances?

    Mushroom spawn will naturally develop a white (or yellow for Chicken of the Woods) mold-like layer called mycelium. This branching network of threads is the primary body of fungi, or vegetative structure. (A good analogy is to imagine mycelium like an apple tree, and a mushroom like an apple grow...

  • Is North Spore grain spawn organic?

    Yes, our grain spawn is USDA Certified Organic.

  • Uncolonized grain spawn

    We select only the highest quality, fully colonized spawn to package up and ship out to you. If when you receive your spawn it looks uncolonized or it's difficult to see the mycelium, it's likely that the spawn was broken up in transit. That sort of physical agitation separates the grain making t...

  • What is your grain spawn made of?

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

  • What kind of yield can I expect from your grain spawn?

    Unfortunately, it is difficult to estimate the overall yield of any project. This is because there are many ways to use grain spawn, many types of substrates, and every growing environment is unique.

  • What substrate should I use with my grain spawn?

    It depends on what your mushroom species prefers. The most common fruiting substrates are manure, hardwood, sawdust, compost, or straw. Please see our Mushroom Substrate Compatibility Guide for a better understanding of what your specific species will grow on here.

  • What type of bags does your grain spawn come in?

    We use a gusseted 2.2 mil polypropylene bag with a high efficiency .2 micron filter patch.

  • When do you use grain spawn vs. sawdust spawn?

    You can use either type of spawn interchangeably outdoors. (Note: Grain spawn cannot be used for log inoculation.) Some people prefer sawdust spawn for outdoor beds and containers as it contains less grain which can be appealing to the critters in your yard.