Growing your own mushrooms with indoor, home mushroom grow kits is easy and fun! Producing Mushroom Kits since 1998 in the USA. All GMHP Mushroom Kits Organic, Non GMO and Made & Grown in the USA. Shiitake Mushroom Kits – Blue Oyster Mushroom Kits – King Oyster Mushroom Kits – Lion’s Mane Mushroom Kits – Sonoma Brown Oyster Mushroom Kits – Student & Educator’s Mushroom Kit