Biochar substrates for horticulture

The Netherlands has no shortage of greenhouses — and the growing media inside them is overdue for a rethink.

Together with HAS green academy, we're running trials comparing rock wool with biochar as a substrate for tomatoes - a project close to our hearts. Here's why it matters:

Conventional substrates — peat, perlite, rock wool, coco coir — come with a heavy carbon footprint and are often energy-intensive to produce. Peat is already being phased out. The industry needs quality, climate-positive alternatives.

Enter biochar.

Early results are promising: biochar-grown tomatoes are performing on par with rock wool. And we're just getting started — blended substrates are showing real potential for what comes next.

Perhaps best of all? The biochar substrates can be reused several times as substrate but also as ingredient for a new substrate blend (as opposed to rock wool) and once the growing cycles are done, biochar substrates can be returned to the soil, where they continue to sequester carbon and improve soil health long-term.

This is what circular growing looks like. More to come.