Big Foot™ Mycorrhizae Concentrate

Big Foot™ Mycorrhizae Concentrate is a liquid root inoculant from BFG Supply that combines four species of endomycorrhizae with softwood biochar, kelp, worm castings, humic acid, trace minerals, and micronutrients. It is designed to be diluted in water and applied at transplant or to established plants, with the goal of improving root colonization, reducing transplant shock, and supporting healthy root development organically. It is OMRI Listed and holds CDFA certification as an organic input material.

Big Foot™ Mycorrhizae Concentrate Specifications

The table below lists the core specifications for Big Foot™ Mycorrhizae Concentrate as sourced from the manufacturer and supplier documentation.

Specification	Value
Product Type	Mycorrhizal root inoculant concentrate (liquid)
Mycorrhizae Species	4 endomycorrhizal species: Glomus intraradices (syn. Rhizophagus intraradices), G. aggregatum, G. etunicatum, G. mosseae
Supporting Ingredients	Softwood biochar (Douglas Fir), kelp, worm castings, humic acid, trace minerals, micronutrients
Weight	1.799 lb
Certifications	OMRI Listed; CDFA Certified Organic Input Material; Jeff Lowenfels “Teaming with Microbes Approved”
Application Methods	Soil drench, liquid root dip, cube soak
Dilution Required	Yes — must always be diluted in water before use
Irrigation Compatibility	Compatible with drip lines passing through 90# mesh screen and most irrigating emitters
SKU	BFC04 (BFG Supply)

Why Choose Big Foot™ Mycorrhizae Concentrate

Many root inoculants on the market rely on mycorrhizal spore count alone as their primary selling point. Big Foot Concentrate takes a different approach: the formulation pairs its mycorrhizal spores with a set of supporting ingredients specifically chosen to promote and sustain colonization. The rationale, as described in the manufacturer’s own documentation, is that spore count matters less than whether the spores successfully establish a symbiotic relationship with the root system. The biochar, kelp, humic acid, and worm castings in this product are included to create the conditions for that colonization to happen reliably.

• Four endomycorrhizal species in one product. The concentrate includes G. intraradices, G. aggregatum, G. etunicatum, and G. mosseae — four distinct species that colonize plant roots differently and collectively improve the odds of successful establishment across a range of soil types and growing media.
• Colonization-promoting ingredient stack. The softwood biochar (sourced from Douglas Fir), kelp meal, worm castings, and humic acid are included to create a root-zone environment that supports mycorrhizal establishment, not just spore delivery.
• Liquid format works across multiple application methods. Because the concentrate is diluted in water, it can be applied as a soil drench, liquid root dip, or cube soak. It also runs through drip lines equipped with 90# mesh screen and most standard irrigating emitters, which means it fits into automated feed schedules.
• Stand-alone all-in-one root inoculant. Big Foot Concentrate is described by the manufacturer as a stand-alone product — you do not need to stack multiple separate inoculants alongside it. It addresses transplant shock, pathogen suppression, germination support, and root vigor in a single application.
• OMRI Listed and CDFA certified organic. Both certifications confirm the product meets requirements for use in certified organic production systems. The product has also earned the Jeff Lowenfels “Teaming with Microbes Approved Product” certification, which independently tests organic microbial products for performance and label accuracy.

Best Uses for Big Foot™ Mycorrhizae Concentrate

Big Foot Concentrate is suited to any grow where establishing strong, healthy roots is the priority — whether that is starting fresh from seed or clone, transplanting into a new container, or supporting plants that are already in the ground or growing medium.

• Transplanting seedlings or rooted clones. Applying the diluted concentrate at the moment of transplant is one of the most effective ways to use this product. The mycorrhizal spores come into direct contact with young roots during a high-stress period, which is when colonization is most beneficial for reducing transplant shock.
• Cube soaks for cuttings and seedlings. Rockwool cubes, rapid rooter plugs, and similar propagation media can be soaked in diluted Big Foot Concentrate before inserting cuttings or seeds. This pre-charges the root zone with beneficial fungi before the plant even begins to root.
• Soil drenches for established plants. Because the liquid can be mixed into a standard watering solution, it can also be applied to plants already growing in containers or raised beds. This is useful when adding mycorrhizal biology to existing plants or re-inoculating after a soil replacement.
• Drip-irrigated systems. The concentrate passes through 90# mesh screen and most drip emitters, so it can be introduced through an automated drip line without clogging hardware. This makes it practical for larger grows where hand-drenching every plant individually is not feasible.
• Organic and certified growing operations. Both the OMRI listing and CDFA certification make Big Foot Concentrate appropriate for use in certified organic systems where synthetic inputs are not permitted. If you are running an organic program alongside a root-support additive like Advanced Nutrients Tarantula, Big Foot Concentrate offers a comparable mycorrhizae-focused option that fits within organic certification requirements.

Big Foot™ Mycorrhizae Concentrate vs Similar Root Inoculants

Root inoculants vary significantly in formulation strategy. Some products focus on spore density alone, delivering a high count of mycorrhizal spores without additional supporting ingredients. Big Foot Concentrate takes a different formulation approach: the spore count is paired with biochar, kelp, worm castings, and humic acid, which the manufacturer describes as ingredients that “promote and stimulate colonization.” The argument is that getting spores to successfully colonize roots matters more than raw spore density.

Granular root inoculants are applied directly to the root zone at planting time and do not require dilution. Big Foot also makes a granular version (Big Foot Granular) for growers who prefer that format. The concentrate format, by contrast, is more flexible: it can be mixed into any watering solution, used as a root dip, or introduced through a drip system. For growers running automated irrigation, the liquid format is generally more practical. For hand-planting in soil, granular is often simpler to apply accurately.

Compared to root additives that combine mycorrhizae with a broader set of bacteria and fungi (such as products blending trichoderma, beneficial bacteria, and multiple endo- and ectomycorrhizal species), Big Foot Concentrate focuses on the four endomycorrhizal species most relevant to annual crops and garden plants. If your primary goal is mycorrhizal colonization rather than broad-spectrum microbial diversity, a product purpose-built around endomycorrhizae like Big Foot Concentrate is a straightforward fit. Growers who want to complement it with a dedicated root stimulant or organic carbon source may also consider pairing it with Earth Juice Hi-Brix Molasses, which supports microbial activity in the root zone.

Compatibility

Big Foot Concentrate is designed to work across a range of growing environments and media types. Because it is a liquid concentrate that must be diluted in water before use, it integrates with any irrigation method that can deliver a diluted liquid solution to the root zone.

• Growing media: Suitable for use in soil, soilless mixes, coco coir, peat-based media, and rockwool/propagation cubes. Endomycorrhizal species in this product are specifically adapted to colonize the roots of most annual crops, vegetables, herbs, and flowering plants grown in these media.
• Irrigation systems: Compatible with drip lines equipped with 90# mesh screen and most standard irrigating emitters. Not intended for use in recirculating hydroponic reservoirs where living microbial products can destabilize water chemistry.
• Organic programs: OMRI Listed and CDFA certified, meaning it is approved for use in certified organic production under the National Organic Program (NOP) and California Department of Food and Agriculture organic input requirements.
• Other root additives: If you are also using a dedicated root stimulant or heavy root-zone additive, check manufacturer guidance on stacking microbial products. Big Foot Concentrate is formulated as a stand-alone inoculant, but it can be part of a broader organic nutrition program. For heavy root-zone support at larger scale, some growers look at products like Heavy 16 Roots as a complementary root-zone amendment in separate applications.
• Chemical fertilizers: High-concentration synthetic fertilizer solutions applied simultaneously with mycorrhizal inoculants can inhibit spore germination and colonization. It is generally recommended to apply mycorrhizal inoculants at or just before transplant, before introducing full-strength synthetic nutrient programs.

Usage Guidelines

Big Foot Concentrate must always be diluted in water before application — do not apply it undiluted. The three supported application methods are soil drench, liquid root dip, and cube soak. Specific dilution rates are not published in the supplier documentation available for this listing; refer to the product label for the manufacturer’s current recommended rates.

1. Shake or stir the concentrate thoroughly before measuring. Sediment or settled particles are normal in a product that contains biochar, worm castings, and organic solids.
2. Measure the recommended dose per gallon (or litre) of water as specified on the product label. Use a calibrated syringe or measuring cup for accuracy.
3. Mix the diluted solution thoroughly before application. The product should be evenly distributed in the water before use.
4. Apply by one of the three methods:
   • Soil drench: Water the root zone with the diluted solution at or just after transplant.
   • Liquid root dip: Dip bare roots or root plugs into the diluted solution before planting.
   • Cube soak: Soak rockwool cubes or propagation plugs in the diluted solution before inserting cuttings or seeds.
5. For drip system use: Confirm your drip emitters and in-line filters are rated for 90# mesh screen or finer. Run fresh water through the lines after application to clear any organic solids from the emitters.
6. Timing: Mycorrhizal inoculants are most effective when applied at or just before transplant, when young roots are actively growing and seeking colonization partners. Applying to established plants is also valid but colonization rates may be lower than at transplant.

Sources & Further Reading