Description:
<jats:p>Engineered soil mixes are expected to maintain plant growth while minimizing nutrient leaching in greenhouse and bioretention applications. Iron (Fe) has been suggested within plant growth mixtures as a sorbent for phosphorus. The purpose of this study was to determine if Fe filings are an appropriate component of engineered plant growth mixtures. Iron filings were added to engineered soil mixes in laboratory columns, and plants were grown for 2 mo. Unfortunately, Fe filings partially cemented the engineered mixes, especially the treatment with sand and compost but no soil. After completing the study, orange and red aggregates were apparent. Although Fe filings might be useful in filter beds, they were not suitable within engineered plant growth mixes.</jats:p><jats:p>Core Ideas
<jats:list list-type="bullet">
<jats:list-item><jats:p>Iron added to sand mix resulted in partial cementation.</jats:p></jats:list-item>
<jats:list-item><jats:p>New red and orange aggregates were formed in the sand mix.</jats:p></jats:list-item>
<jats:list-item><jats:p>Iron should not be added to soil mixes where plants will be grown.</jats:p></jats:list-item>
</jats:list>
</jats:p>