Extension Explainers

Sieve reports only measure width, but particle shape—whether elongated or circular—actually dictates air space and drainage. This research categorizes materials into "Shape Classes," showing how needle-like fibers prevent compaction while rounder materials like bark offer predictable stability. Understanding these 3D interactions allows you to customize your rootzone for better performance.

• Nursery crops use a lot of phosphorus fertilizer because it is essential for general health and vigor. 
• Excess phosphorus can leach (drain) out of pots and run off into nearby surface water.
• This runoff causes water pollution, leading to nutrient overload and algal blooms that harm aquatic ecosystems
• Certain counties have fees for nitrogen leaching.
• Leaching is especially common in nurseries using pine bark-based substrates.
• Phosphorus loss is not only bad for the environment, but also expensive for growers snce they must replace lost fertilizer
• The study’s goal is to reduce phosphorus leaching by adding a layer of ferrous sulfate–amended pine bark to the bottom of nursery pots

• Growers are exploring processed wood as a partial peat substitute. In this radish damping-off model, peat+wood blends were never worse than peat+perlite and were often better, especially with disc-refined (FG) and hammer-milled (PTS) wood.
• Results are crop- and pathogen-specific; treat as promising evidence, but not universal proof. Because of this new substrate mixes such as engineered wood are being considered as a replacement or partial substitution.
• This study helps answer a few preliminary questions about disease spread in processed wood substrates but also serves as a starting point for deeper and more varied analysis of alternative soilless substrates.

Field production faces mounting challenges from disappearing fumigants and extreme weather, prompting a massive industry shift. Over 73% of specialty growers now use soilless substrates to reclaim rootzone control, improving crop uniformity and disease management. This guide explores how transitioning to lighter, pathogen-free media slashes freight costs and simplifies food safety audits while maximizing spatial efficiency.

Growers often worry that sustainable biochar will "soak up" expensive PGR drenches like paclobutrazol, but new research confirms that wood-based biochar up to 30% does not interfere with growth control. Whether growing sensitive pansies or poinsettias, standard rates remain fully effective, avoiding hidden chemical costs. This article details results while highlighting potential pH management benefits.