Your Canadian Distributor of Unicorn Mushroom Bags

Grow Mushrooms Canada has used Unicorn filter patch bags for our grain spawn and mushroom kits since 2018. We are thrilled to be your Canadian distributor, offering the lowest prices to your door.

Lowest Prices. Free Shipping.

Bulk Discounts Mix & Match

Save 2% when you buy 2+ boxes
Save 5% when you buy 5+ boxes
Save 2% more when you pay by etransfer*

*Request e-transfer discount in customer notes during checkout, and we will email you a discounted invoice to pay. If you find a lower price including shipping and brokerage, give us a chance to beat it!

Filter patch bags were a game changer in the history of mushroom growing.

Unicorn’s mushroom growing bags are designed to be filled with substrate, then sterilized in an autoclave or pressure canner. Once inoculated and sealed, the bags allow for air exchange through a special have a filter patch, while keeping contamination out.

We do our best to keep a wide selection of these USA-made bags in stock so that Canadian growers have quick access. Ships within 2 business days from BC Canada, with no hassle at the border, nor unexpected brokerage, duty or exchange rate.

Stock is Limited. Pre-Order to Ensure Your Supply at Biggest Savings!

While we strive to keep a wide selection of Unicorn bags in stock, the high overhead limits our quantity, and at times we sell out of popular types. We encourage you to order in advance to ensure your continuous supply, and to take advantage of opportunities to "pre-order" at the biggest savings of all. Join our list to be notified of opportunities to pre-order at the biggest discount.

Autoclavable Bag & Filter Types

When you are using a bag with no port you need to inoculate with mushroom culture in front of a flow hood using sterile technique, then heat seal the bag. T filter 0.2 micron recommended for grain spawn, and A filter 0.5 micron for fruiting blocks.

No need for an expensive flow hood to maintain sterility with these autoclavable injection port bags. Simply inject liquid culture through the port, to inoculate your substrate while keeping contamination out.

Non-Autoclavable Bags

Not all mushroom growing requires full sterility, and it is possible to grow in a bag without a filter patch.

These bags are ideal for stuffing with straw that has just cooled from pasteurization, and mixed with strong cultures such as oyster mushrooms. Air exchange is still important to provide, and can be achieved by wrapping an elastic around a plug of polyfill at top of bag, or poking pin holes evenly spaced throughout the bag surface. These bags are not autoclavable and can not be used in a pressure cooker or they will melt.