Biochar-compost mixtures added to simulated golf greens increases creeping bentgrass growth

Mixtures of 85% sand meeting United States Golf Association (USGA) and 15% mixtures of peat (control), a commercial biochar, a commercial biochar-compost product (CarbonizPN), and seven biochar-commercial compost mixtures were tested on the growth of creeping bentgrass (Agrostis stolonifera  L. “007) in simulated golf greens.  Physical properties including pH, bulk density, pore space, compaction distance, and water/nutrient content varied among the mixtures.  Bentgrass plant heights, root lengths, and fresh and dry weights were evaluated in mixtures grown in polyvinyl chloride tubes mimicking a USGA root zone.  Forty days after seeding, plants grown in 5% biochar and 10% Chicago Sanitary District Solids had significantly greater fresh weights, dry weights, and shoot heights than the control.  Dry weights and shoot heights were also higher than the control in bentgrass grown in the 15% CarbonizPN mixture. Based on these results the addition of certain biochar-compost mixtures would improve overall plant growth in sand-based root zones.