Investigating the Efficacy of Reusable Grow Bags in Specialty Mushroom Cultivation to Reduce Single-Use Plastic

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2024: $24,899.00
Projected End Date: 04/30/2025
Grant Recipient: Bridgetown Mushrooms
Region: Western
State: Oregon
Principal Investigator:
Trevor Huebert
Bridgetown Mushrooms


  • Miscellaneous: mushrooms


  • Crop Production: municipal wastes
  • Education and Training: farmer to farmer
  • Sustainable Communities: infrastructure analysis

    Proposal summary:

    Mushroom cultivation generates
    roughly 1-2 million tons of polypropylene (PP) and high-density
    polyethylene (HDPE) plastic waste per year globally, with 3 tons
    of plastic coming from Bridgetown Mushrooms alone. A reusable
    alternative to single-use plastic grow bags would significantly
    reduce plastic waste. This project will test the feasibility of a
    reusable grow bag made of silicone rubber (SR) and compare
    growing outcomes with current single-use PP bags.

    Previously, Bridgetown Mushrooms
    partnered with the Oregon Applied Sustainability Experience,
    funded by US EPA, to investigate effective alternatives to PP
    bags. Solutions explored had significantly lower production
    rates, higher costs, or infrastructure requirements infeasible
    for the company. The company distributed an industry survey and
    interviewed nine experts, all of which expressed concern about
    plastic waste in the industry. Findings concluded that while
    there is not a simple solution, there is collective desire to
    reduce waste and explore reusable bags. 

    SR stands out as a potentially
    suitable material for reusable bags. SR can be used indefinitely
    at 300°F with minimal deterioration. This project seeks to test
    an initial concept of a reusable bag made of SR to determine its
    viability. Working with material specialists, Bridgetown
    Mushrooms will develop and compare a reusable bag made of SR with
    the current standard PP bag. Lessons learned from this project
    could pave the way for eliminating the majority of plastic waste
    in the industry. Potential outcomes would be the elimination of
    at least 78,000 single-use plastic bags (3 tons) per year at
    Bridgetown Mushrooms alone, and collaboration with the industry
    for broader development and adoption.

    Bridgetown Mushrooms will develop
    a fact sheet and accompanying graphics to distribute via its
    social media channels and website, will share information at an
    industry conference, and will initiate a pledge for cultivators
    to reduce plastic waste in the mushroom industry.

    Project objectives from proposal:

    Research Objectives:

    1. Assess the difference in biological efficiency between
      fruiting blocks cultivated in reusable silicone rubber (SR) bags
      and standard polypropylene (PP) bags.
    2. Evaluate the variance in contamination levels for the
      treatment (SR) and the control (PP).
    3. Determine the longevity of prototype reusable SR bags when
      subjected to continual heat exposure in an autoclave.
    4. Establish the financial cost and feasibility of adopting
      reusable silicone bags.

    Educational Objectives:

    1. Raise awareness and promote reusable growing bags to
      professional mushroom cultivators and hobbyists.
    2. Engage with stakeholders and build community support for
      alternatives to single-use plastic growing bags.
    3. Introduce a pledge for cultivators to reduce plastic waste in
      the mushroom industry.
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.