Being a neighbour to Niagara College (NC), Walker Industries has created an ongoing and positive partnership with NC’s Horticultural & Environmental Sciences Innovation Centre (HESIC).

One of the areas of focus for Walker, led by Greg Robles, Manager Innovation & Optimization, Environmental Division, is the conversion of wood fiber residuals to renewable gases and solid biocarbon through a process known as high temperature pyrolysis. The technology utilizes a kiln specifically designed to heat feedstock to temperatures as high as 900°C in an oxygen-free environment, where the material undergoes pyrolysis. Pyrolysis is a process to chemically decompose organic materials at elevated temperatures in the absence of oxygen. During this process, organic materials are carbonized and concentrated into a high carbon solid residue (biocarbon), while quantities of synthetic gases (syngas) are liberated.

The resulting solid product, also known as biochar, has been proven to be beneficial to agricultural operations by capturing nutrients in the soil and providing these nutrients back to the crops.

Before biochar is to be used successfully as a soilless greenhouse media enhancement, its blend rate must first be determined, and this is why Walker tapped into HESIC’s expertise to help investigate this innovation challenge.

The risk of excess biochar blended in media is that it may make nutrients less available as roots will be unable to uptake nutrients. If too little biochar is blended with media, there may be insignificant nutrient retention and thus nutrients will be lost in the leachate. 

HESIC researchers created a matrix of biochar and Gro-Bark® greenhouse media, to examine the nutrient content of leachate over time and whether nutrient content within the leachate was affected by the ratio of biochar. This study found that the amendment of Gro-Bark® greenhouse media with biochar increased media cation exchange capacity (CEC) and decreased nutrient loss due to leaching.

The next step was to determine, through a growth trial, the overall impact that the incorporation of biochar had into greenhouse media, on the health of the crops. A research trial was conducted using biochar as a media amendment at volumes of 0% (control), 10%, and 20% in containers to grow basil (Ocimum basilicum) and gerbera (Gerbera jamesonii ‘Flori Line® Midi’) crops.

The addition of biochar to greenhouse potting media appeared to act as a biostimulant, positively influencing both basil and gerbera plant growth. Of the two treatments with biochar, the 10% treatment produced basil that were taller and gave the highest total amount of plant biomass, while the 20% biochar blend produced the highest amount of gerbera biomass. No differences in flowering between treatments were observed in gerbera. The incorporation of biochar increased the media pH prior to planting from 4.9 in the control to 5.3 in the 10% mix, and 6.0 in the 20% blends. This higher pH trend in the biochar-amended media was maintained throughout the growth periods of both crops. The biochar-amended media demonstrated higher nutrient-holding capacity than the control, as they leached fewer nutrients over the course of the growth trial period, while also holding more phosphate, calcium, and potassium in the media blend with increasing rates of biochar.

At the end of it all, this research provides value to Walker because it gives more options to Walker’s R&D team to enhance their products, making it a more versatile option for growers.

In addition to all this valuable research that HESIC has helped Walker complete, there’s the added benefit of being neighbours with the No. 1 research college in Canada and the local pool of talent it generates. Walker is proud to have many NC grads on their team.

“Community is very important to us at Walker. Being neighbours with the College and working as partners has been great to build those ties. We’re happy to continue to work together and we see NC as a talent pipeline as well,” said Greg.

Of course, students working with HESIC were involved in research projects, participating in the regular update meetings, and helping conduct the trials. One unique experience the students received was a tour of the Walker site.

“We organized a tour for the students to come up to our Walker site, which we always like to do. It lets them really look at our composting operation, sit down with our staff and ask questions. At the end of the day, it allows the students to have a better understanding of what we’re doing and what we’re trying to achieve with these projects,” said Greg.

Touring also exposes students to the job opportunities found in resource recovery and waste management and allows them to get valuable facetime with a local industry partner.