Evaluation of leachate over time from selected rates of NEREA® blended with peat moss 

IZ Weights Trial
(Photo courtesy of Niagara College Canada)
To examine the leachate over time from a selected range of NEREA® blended with peat moss

HESIC created multiple NEREA® and peat moss blend ratios to examine the nutrient content of leachate over time, and whether the nutrient content within the leachate was affected by the presence of peat moss

Follow up studies are underway to further evaluate the challenge. One study is often not enough: a pathway of research is critical for innovations that are part of the complex work of horticulture

International Zeolite Corporation (IZ) is an international marketer and supplier of natural zeolite and zeolite-infused products. Zeolite is a naturally occurring mineral found in volcanic ash that can be used for several different products and applications. In horticulture, zeolite can be used within growing media in the form of raw granules or granules embedded with plant nutrients.

Traditional commercial greenhouses use a blended growing media consisting of sphagnum peat moss, perlite (for aeration) and lime. Any nutrients required by a crop are provided at additional expense and effort by the grower.

These nutrients are most commonly in soluble form, needing to be blended with clean water at the correct rate to provide ample nutrients to a growing crop avoiding deficiencies or toxicities, both of which may be damaging to crop success.

IZ has recently established a contractual agreement with the Foundation of the University of Havana, Cuba. Through this collaboration, IZ has acquired permission to test a zeolite-based substrate, embedded with nutrients, developed at the University of Havana called NEREA®, NEREA® has the potential to be blended with peat moss to create a novel growing media with the necessary physical and chemical characteristics for plant growth. However, we don’t know to what extent nutrients may be lost when watered multiple times. 

Raw zeolite is used to prepare NEREA® by considering the combined chemical composition of raw materials and the plants’ requirements of all essential nutrients for a growing season. Combined with the potential to provide nutrients in a growing media, the consistent 3 mm sizing of the NEREA® particles suggests that it can also provide media aeration like that of perlite. It’s not yet known whether these nutrients held with NEREA® are lost, or leached, from NEREA® when watered in a container pot or whether the presence of peat moss may affect the outcome. 

IZ approached Niagara College’s Horticultural & Environmental Sciences Innovation Centre (HESIC) team to create multiple NEREA® and peat moss blend ratios to examine the nutrient content of leachate over time. They wanted to understand whether nutrient content within the leachate was affected by the presence of peat moss. A total of six leachate samples were collected over a period of fourteen days and analysed for complete nutrient content.

Results showed that NEREA® does leach a significant amount of nutrients over six waterings. The presence of peat moss didn’t appear to affect the degree of nutrient loss, however, there was correlation between the rate of NEREA® decreasing and the decrease in concentration of nutrients leached.

This study didn’t include washing or rinsing NEREA® prior to blending with peat moss, nor did it measure crop growth effects on the final leachate concentrations. Both avenues of nutrient loss mitigation are being evaluated in a follow-up study. 

An interesting pH trend was observed in that NEREA® increased the pH of the peat moss-based media, as the proportion of NEREA® increased. It can be surmised that, with the addition of between 10 to 25% NEREA® in raw peat moss, the amount of lime used to increase pH can be reduced or possibly eliminated.

Nutrients in anion form, nitrate, and phosphate in particular, leach in very high concentrations from NEREA® and peat moss blends. Both ions are of environmental concern, particularly when leached into the watershed.

Nitrates and phosphates are known contributors to algal growth in streams and lakes, and thus linked to reduction of health in these bodies of water. The loss of phosphates and nitrates off-site are of high importance in all agricultural facilities and are monitored by local conservation authorities. 

During the project, the actual (or expected) total nutrient content in NEREA® wasn’t known to researchers making it difficult to conclude proportion of nutrient loss compared to nutrients retained within the zeolite particles.

What we can confirm from this study is that nutrient loss from NEREA® does occur. While this study concludes that nutrients leach from NEREA® and NEREA®-peat moss blends, it did not include washing or rinsing the NEREA® prior to blending with peat moss, nor did it measure crop growth effects, use of lime to adjust pH, or effect of perlite in the media blend, on final leachate concentrations.

If NEREA® is washed prior to use, some nutrient will remain in NEREA® while the leachate from the washing stage can be reused in the production of the product. There is a possibility that in the presence of a growing crop, with living roots taking up available nutrients, the concentrations of various nutrients may be affected.

Moving forward, the plan is to study the above scenarios to expand on the findings of this project. The team wants to investigate the effect of washing NEREA® prior to blending with peat moss on plant growth.

International Zeolite Corp. and Niagara College’s Horticultural & Environmental Sciences Innovation Centre (HESIC) have an ongoing agreement in place that provides priority and support for research projects in relationship to IZ’s proprietary NEREA® technology, which will be carried out by HESIC.

This project is funded by the Government of Canada through the Federal Economic Development Agency for Southern Ontario

Visit Niagara College’s Horticultural & Environmental Sciences Innovation Centre page to learn more about its resources and capabilities.