From Waste to Growth: Developing Sustainable Growing Media for Seedling Production

Priority research theme: Carbon Capture & Utilization
Awarded: Winter 2026

Overview

Growing demand for forest products and climate action is increasing the need for tree seedlings, driven by initiatives such as the 2 Billion Trees Program and the Bonn Challenge. However, most seedlings are currently grown in peat-based media. Peat is harvested from wetlands—ecosystems that store significant carbon and support biodiversity. Its extraction releases greenhouse gases, degrades these environments, and reduces their long-term carbon storage capacity.

At the same time, large volumes of organic byproducts from urban, industrial, agricultural, and forestry activities—such as biosolids, bark, wood chips, and compost—are often sent to landfills, where they decompose and emit greenhouse gases. Many of these materials have properties that could make them suitable alternatives to peat, presenting an opportunity to support a circular economy in Atlantic Canada.

This project aims to develop and test sustainable, locally sourced growing media using these byproducts to cultivate key tree species, including black ash (Fraxinus nigra), sugar maple (Acer saccharum), and white spruce (Picea glauca)—all of which are ecologically, economically, and culturally important and currently facing pressures from climate change.

The project will:

• Assess the availability and properties of major organic byproducts in New Brunswick
• Develop and test alternative growing media using different material combinations
• Conduct life-cycle and cost analyses to measure environmental and economic benefits

Expected outcomes include reduced reliance on peat, lower greenhouse gas emissions from seedling production, and the creation of new local markets for organic byproducts. The project will also improve methods for producing high-quality seedlings to support reforestation efforts.

Overall, this work will advance more sustainable seedling production systems, strengthen regional economies, and contribute to Canada’s net-zero and biodiversity goals.