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Mycorrhizal fungi are naturally occurring in many soil types around the world. However, their presence in soil is greatly reduced by soil disturbance, due to incorporated amendments that are exempt of these beneficial organisms, plowing and removal of top soil in construction sites. As a result, there is little mycorrhizal fungi found in soils from landscapes or newly prepared beds. In addition, mycorrhizal fungi do not naturally occur in growing media used for containerized plants. Therefore, mycorrhizal fungi must be added to both outdoor soil and soilless growing media for plants to benefit from them. 

Benefits of Mycorrhizal Fungi: The use of mycorrhizal fungi can play an important role in helping with plant establishment by reducing transplant shock, improving plant resistance to stresses and enhancing nutrient acquisition from the growing medium / soil. This has shown a positive impact on plant health and reduced crop shrinkage. In many research trials, plants inoculated with mycorrhizal fungi have also been found to play a role in improving soil structure and maintaining organic matter levels in the soil, allowing for consistent water retention in the soil from year to year. 

PRO-MIX PUR MYCORRHIZAE ZEOLITE: PRO-MIX PUR MYCORRHIZAE ZEOLITE is a mycorrhizal fungi species, called Glomus intraradices, that colonizes the roots of most horticultural crops, including annuals, perennials, grasses, vegetables and some shrubs. The strain of Glomus intraradices produced by Premier Tech Horticulture is called MYCORRHIZAE and is considered a generalist, in that it colonizes a wide variety of plants.  It is the same mycorrhizae species that is added to the PRO-MIX MYCORRHIZAE growing media line. 

PRO-MIX PUR MYCORRHIZAE ZEOLITE is a granular inoculant available in a concentrated formulation (132 spores per gram of product) that can be used by customers that make their own growing media or landscape planting soils (Figure 1). Only a few plant species such as brassicas, carnations, firs, spruces, orchids, rhododendrons and beets will not become colonized by MYCORRHIZAE; however, MYCORRHIZAE will not have a negative impact on these plants.




PRO-MIX PUR MYCORRHIZAE ZEOLITE is formulated with a zeolite carrier that is highly compatible with MYCORRHIZAE and can be incorporated in most soil line feeders at different rates according to the size of the container used. One 40 lb  (18.2kg) bag will amend 6-21 cubic yards of growing medium, again depending on the container size.  It is dense enough so it doesn’t float to the top of the growing medium after irrigation and blends well into a growing medium / soil. 

It’s important to have enough inoculant in the growing medium so newly formed plant roots can come into contact with MYCORRHIZAE and colonization can occur quickly. Crops will benefit most when PRO-MIX PUR MYCORRHIZAE ZEOLITE is used as early as possible in the crop cycle and MYCORRHIZAE is active immediately in the soil. 

Advantages of PRO-MIX PUR MYCORRHIZAE ZEOLITE:  Once plant roots have been colonized and form a symbiotic relationship with MYCORRHIZAE, mycelia (which look like thin threads as seen in Figure 2) will grow out from the tips of plant roots out into the surrounding soil or growing medium and serve as an extension of the root system (Figure 2). The mycelial network more than doubles the total absorptive area of the root system and helps acquire difficult to reach nutrients like phosphorus, copper and zinc. MYCORRHIZAE makes better use of the fertilizer added to the growing medium / soil, improves water absorption and increases plant tolerance to stresses caused by drought, root disease, excessive salinity and transplant shock. 

Root colonized by Mycorrhizae from PRO-MIX Greenhouse Growing

"Figure 2. The picture on the left shows a plant root that is not colonized by MYCORRHIZAE while the picture on the right shows a root colonized by MYCORRHIZAE (seen in the picture as thin, thread-like structures called mycelia). Source: Premier Tech Horticulture"


For more information, contact your Premier Tech Horticulture Grower Services Representative:

BLOE         PEEJ             LAWL

Ed Bloodnick
Horticulture Director
US-South East

JoAnn Peery
Horticulture Specialist
US-Central, Canada-Central

Lance Lawnson
Horticulture Specialist
US-West, Canada-West


Troy Buechel
Horticulture Specialist
US-North East

Susan Parent
Horticulture Specialist
Canada-East, US-New England

Jose Chen Lopez
Horticulture Specialist
Mexico, Latin & South America



  • Fortin. J. A, et al. 2009. Mycorrhizas: The New Green Revolution. 140pp Ed. Multimonde.

PRO-MIX® is a registered trademark of Premier Horticulture Ltd.

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