Mycorrhizal Inoculant – Hard To Spell, Easy To Use

Mycorrhizal Inoculant

I use mycorrhizal inoculant in my organic garden almost every time I plant and seed. I wouldn’t plant without it.

Update: About 2 1/2 years after writing this, I decided to start selling the mycorrhizal inoculant I use. You can learn more about it here.

Over 95% of plant species form symbiotic relationships with mycorrhizal fungi. The fungi provide nutrients and water to their host plants in exchange for carbohydrates and other goodies.

In fact, many plants will trade more than 50% of their carbohydrates with these fungi and other microbes. Mycorrhizal fungi greatly improve soil characteristics, and are among the most important microbes that form relationships with plants.

Click for video transcription

This transcription will have some mistakes because it is partially automated.

Hey guys! It’s Phil from smilinggardener.com and I’m sitting here in front of the veggie garden and today I’m gonna be talking about mycorrhizal inoculant. I’m sitting really close here, because as you’ll see in a minute the inoculants is very small and I wanna show you exactly how it works.

So mycorrhizal fungi are special, are kinda of special kind of fungi that form a relationship with plants, a symbiotic relationship where they help each other out and actually over 95% of plants form this relationhip with fungi and what happen is the fungi, they effectively, what they do is they attach to the root system of the plants and even go right inside the roots and then they effectively extend that roots system of the plant because the fungi can go much further out to the soil; and get water and nutrients, nitrogen especially phosphorus and some of the heavier, some of the nutrients that the roots have a hard time getting out of the soil.

And the in return for that favor the plants will give a lot of carbohydrate or sugars and vitamins and enzymes and all kinds of living substances, food through the fungi, so it’s this exchange that occurs and plants will give over 50% of the carbohydrates that they make to the fungi and to other microorganisms that do things for them in the soil.

So, you know mycorrhizal fungi they’re another of these microbes that I talked about that we should have in our soil I mean they’re fairly ambiguous in nature, but in our soil they’re often not there because we, if we’ve been tilling, if our soil is compacted, if we haven’t allowed a lot of organic matter to be recycle in there. You know freezing pesticides, chemical fertilizers; if we’ve been withholding water from the landscape like for using drip irrigation.

All kinds of human activities you know can drastically decrease the health and abundance of mycorrhizal fungi in our soil and so it’s a good idea to bring it back in.

There are a couple different kinds, there’s the main kind is called endomycorrhizal fungi, it’s also called arbuscular mycorrhizal fungi; and it’s over, over 90% of species of plants form a relationship with this kind of fungi. So that’s gonna be your, most of your vegetables and grasses and a lot of trees are gonna form that relationship.

There’s also another one called ectomycorrhizal fungi, the endo actually goes right inside, not only inside the plant root, but inside the cells of the plants where is the ecto doesn’t go inside the cell or that’s what I remember about it. The ecto is about maybe, maybe 5% of plants quite a few coniferous trees, evergreen trees and some deciduous trees as well.

So what I often like to do is if I’m gonna be seeding like a big lawn area, I might just go for the endo. But if I’m gonna be seeding a lawn and vegetables and trees, I’ll pay the extra, when I sold this stuff it was about an extra 10% for an endo-ecto blend, so that’s why I usually recommend you go with and you can get that you know from like the Organic Gardener’s Pantry which I used to run that just in Canada.

In the US, I actually found the good brand on a- Amazon, you know it’s starting to become a bigger thing now. It’s been around for awhile but it’s starting to become more well known, so you should be able to find it in a garden center, too.

So when you wanna apply it, you know the ideal time to have this stuff applied is in the nursery when they grow it, but that’s often not happen, usually not happening its started to happen a little more.

But generally, we’re gonna have to do it with ourselves and the best time to do that is when you, when you plant, because you want this to form you, you want this getting contact with the roots of the plants. And so the best time to do that is when you actually have access to the roots.

So I’m gonna show you today just how I would do with seeds, because seed need it too, just to keep the video short I’m not gonna show all the different ways you can do it. But once I get that smilinggardener academy up and running, I’ll show you how to apply it to plants you know, plants and also into the existing garden.

Today, so I have some beans, beans are just one of the many kinds of vegetables that are gonna form the relationship. Actually, almost many vegetables do, there are some that don’t and what I’ll do is put a list down below or if your not on my blog, I’ll put a link down below, you can have on the blog and then I’ll show you the vegetables that you don’t need to apply the fungi with.

So here are some beans, I picked the beans because it’s big enough for me to show you; and here is some mycorrhizal fungi powder, I have it in a powdered form. I always tended, I just sold the powered form because it goes through a sprayer as well and sometimes its use for a product for the sprayer.

You can also get it more in granules, I like the powder and it’s purely its helpful coz the powder you can rub right on to the plant roots or rub on to the seed. So all I would do is I would follow the instructions for how much you need to used it depends on how much the kind you buy.

But I, I would take all my seeds and I just have in a jar something and I just rub them all to the fungi. All you need is a little bit fungi to get on there. I doubt you can see that. Yeah! You could see that. That’s coated, I mean that’s plenty, all you need is a little bit.

Another thing that I would do those, I tend to soak my seeds overnight before I plant them, not so much bean seeds like humus, I’ve learned that you don’t really want to soaked them for too long. But most seeds that I do soaked them in a mixture of kelp and water and usually sea minerals, I’ll talk about that in other time.

But here are some that I, I just soaked, and I put that in there. It really sticks really nicely. So usually I’m putting mycorrhizal fungi on to something that’s been soaked.

I don’t have a, I don’t a plant to show you today because it’s the middle summer and that’s the other reason, I’m not gonna show you our plant it, but if I did, if I had to say a little basal or something I’ll take it out from its pot and I’ll just rub a- like half a teaspoon of this stuff onto the roots. I don’t have to cover the whole roots as long as you get a little bit of the roots, there are hundred of thousands of spores, you know in a pound of this, of this stuff.

So like, I’m gonna have thousand or hundreds or thousand of spores here and just rub that on the roots and your good to go.

I think that’s all I wanna talk about to you today, I know I can get a lot more into this in the academy when I have more time and but I—I think that’s good for now. So, if you want to, if you wanna see which vegetables you don’t need to use this with you can go check it out on the blog.

While you’re there you can signed up for my 15 Vital Lessons for Becoming a Better Organic Gardener which are these 15 Lessons that I thought that really cool when I was first learning about organic gardening.

So I give those away for you free, you can get those right on the main page and that’s all for now about mycorrhizal inoculant. So I’ll see you next week.

Hey guys! It’s Phil from smilinggardener.com and I’m sitting here in front of the veggie garden and today I’m gonna be talking about mycorrhizal inoculant. I’m sitting really close here, because as you’ll see in a minute the inoculants is very small and I wanna show you exactly how it works.

So mycorrhizal fungi are special, are kinda of special kind of fungi that form a relationship with plants, a symbiotic relationship where they help each other out and actually over 95% of plants form this relationhip with fungi and what happen is the fungi, they effectively, what they do is they attach to the root system of the plants and even go right inside the roots and then they effectively extend that roots system of the plant because the fungi can go much further out to the soil; and get water and nutrients, nitrogen especially phosphorus and some of the heavier, some of the nutrients that the roots have a hard time getting out of the soil.

And the in return for that favor the plants will give a lot of carbohydrate or sugars and vitamins and enzymes and all kinds of living substances, food through the fungi, so it’s this exchange that occurs and plants will give over 50% of the carbohydrates that they make to the fungi and to other microorganisms that do things for them in the soil.

So, you know mycorrhizal fungi they’re another of these microbes that I talked about that we should have in our soil I mean they’re fairly ambiguous in nature, but in our soil they’re often not there because we, if we’ve been tilling, if our soil is compacted, if we haven’t allowed a lot of organic matter to be recycle in there. You know freezing pesticides, chemical fertilizers; if we’ve been withholding water from the landscape like for using drip irrigation.

All kinds of human activities you know can drastically decrease the health and abundance of mycorrhizal fungi in our soil and so it’s a good idea to bring it back in.

There are a couple different kinds, there’s the main kind is called endomycorrhizal fungi, it’s also called arbuscular mycorrhizal fungi; and it’s over, over 90% of species of plants form a relationship with this kind of fungi. So that’s gonna be your, most of your vegetables and grasses and a lot of trees are gonna form that relationship.

There’s also another one called ectomycorrhizal fungi, the endo actually goes right inside, not only inside the plant root, but inside the cells of the plants where is the ecto doesn’t go inside the cell or that’s what I remember about it. The ecto is about maybe, maybe 5% of plants quite a few coniferous trees, evergreen trees and some deciduous trees as well.

So what I often like to do is if I’m gonna be seeding like a big lawn area, I might just go for the endo. But if I’m gonna be seeding a lawn and vegetables and trees, I’ll pay the extra, when I sold this stuff it was about an extra 10% for an endo-ecto blend, so that’s why I usually recommend you go with and you can get that you know from like the Organic Gardener’s Pantry which I used to run that just in Canada.

In the US, I actually found the good brand on a- Amazon, you know it’s starting to become a bigger thing now. It’s been around for awhile but it’s starting to become more well known, so you should be able to find it in a garden center, too.

So when you wanna apply it, you know the ideal time to have this stuff applied is in the nursery when they grow it, but that’s often not happen, usually not happening its started to happen a little more.

But generally, we’re gonna have to do it with ourselves and the best time to do that is when you, when you plant, because you want this to form you, you want this getting contact with the roots of the plants. And so the best time to do that is when you actually have access to the roots.

So I’m gonna show you today just how I would do with seeds, because seed need it too, just to keep the video short I’m not gonna show all the different ways you can do it. But once I get that smilinggardener academy up and running, I’ll show you how to apply it to plants you know, plants and also into the existing garden.

Today, so I have some beans, beans are just one of the many kinds of vegetables that are gonna form the relationship. Actually, almost many vegetables do, there are some that don’t and what I’ll do is put a list down below or if your not on my blog, I’ll put a link down below, you can have on the blog and then I’ll show you the vegetables that you don’t need to apply the fungi with.

So here are some beans, I picked the beans because it’s big enough for me to show you; and here is some mycorrhizal fungi powder, I have it in a powdered form. I always tended, I just sold the powered form because it goes through a sprayer as well and sometimes its use for a product for the sprayer.

You can also get it more in granules, I like the powder and it’s purely its helpful coz the powder you can rub right on to the plant roots or rub on to the seed. So all I would do is I would follow the instructions for how much you need to used it depends on how much the kind you buy.

But I, I would take all my seeds and I just have in a jar something and I just rub them all to the fungi. All you need is a little bit fungi to get on there. I doubt you can see that. Yeah! You could see that. That’s coated, I mean that’s plenty, all you need is a little bit.

Another thing that I would do those, I tend to soak my seeds overnight before I plant them, not so much bean seeds like humus, I’ve learned that you don’t really want to soaked them for too long. But most seeds that I do soaked them in a mixture of kelp and water and usually sea minerals, I’ll talk about that in other time.

But here are some that I, I just soaked, and I put that in there. It really sticks really nicely. So usually I’m putting mycorrhizal fungi on to something that’s been soaked.

I don’t have a, I don’t a plant to show you today because it’s the middle summer and that’s the other reason, I’m not gonna show you our plant it, but if I did, if I had to say a little basal or something I’ll take it out from its pot and I’ll just rub a- like half a teaspoon of this stuff onto the roots. I don’t have to cover the whole roots as long as you get a little bit of the roots, there are hundred of thousands of spores, you know in a pound of this, of this stuff.

So like, I’m gonna have thousand or hundreds or thousand of spores here and just rub that on the roots and your good to go.

I think that’s all I wanna talk about to you today, I know I can get a lot more into this in the academy when I have more time and but I—I think that’s good for now. So, if you want to, if you wanna see which vegetables you don’t need to use this with you can go check it out on the blog.

While you’re there you can signed up for my 15 Vital Lessons for Becoming a Better Organic Gardener which are these 15 Lessons that I thought that really cool when I was first learning about organic gardening.

So I give those away for you free, you can get those right on the main page and that’s all for now about mycorrhizal inoculant. So I’ll see you next week.

This is another of those microbes that should be in our soil, but often isn’t anymore. In soil that has been tilled, compacted, water logged, treated with chemicals, or left without plant cover, mycorrhizal fungi may be seriously lacking.

They aren’t present in imported topsoil or potting soil mix either, and don’t multiply in compost. In any of these scenarios, they need to be added back to the soil, especially when planting or seeding, as they’re essential to optimum plant health.

We can inoculate our plants with mycorrhizal inoculant by taking just a small bucket of soil from a healthy environment that contains the right fungi, or by buying mycorrhizal fungi products from a garden center or online. While the first method sounds like more fun to me, I’ve always gravitated to the second because I know what I’m getting.

Types Of Mycorrhizal Inoculant

There are two main categories of mycorrhizal fungi. Over 90% of plants form relationships with endomycorrhizal fungi, also called arbuscular mycorrhizal fungi. You need them for most of your vegetables, grasses and many ornamentals.

About 5% of plants, including many conifers and some deciduous trees, form relationships with ectomycorrhizal fungi. When you’re planting a mix of plants, you can often buy a mixture of endomycorrhizal and ectomycorrhizal fungi and just use that for everything.

How To Apply Mycorrhizal Spores

The best time to apply mycorrhizal inoculant is at the nursery during the plant production stage, but since your plants probably didn’t have that done, the next best time is at planting/seeding/sodding. This will allow you to establish contact between the fungi and plant roots, which is important because that’s where the relationship occurs.

There’s no benefit to foliar feeding with mycorrhizal fungi, as they need to touch the roots. We can, however, mix them with biostimulants before application. Mycorrhizal products shouldn’t need to be applied more than once to each plant, unless your management practices are harming them.

Rub the fungi directly on the root ball if possible, or sprinkle in the planting hole. For seed, mix it dry with the seed before spreading. For sod, get a powder form of the fungi, mix with water, and spray it on the soil right before you lay the sod, or even better, right on the bottom of the sod. You could spray it on afterwards as well and water it down to the root zone.

While not as good, the other choice is to apply the product to existing landscapes. The powder form is best for mixing with water to get the spores to infiltrate into the soil. For turf, it’s better to do this right after aerating so more of the spores get down to the roots. Otherwise, it can be watered in, but will not be as effective on heavy clay or very compacted soils.

Vegetable Plants That Don’t Use Mycorrhizal Fungi

There are some plants that generally do not form relationships with mycorrhizal fungi. The most important for vegetable gardeners is the Brassicaceae family:

  • broccoli
  • brussels sprouts
  • cabbage
  • cauliflower
  • collards
  • kale
  • mustard
  • rutabaga

… and members of the Amaranthaceae family:

  • beets
  • swiss chard
  • lamb’s quarters
  • quinoa
  • spinach
  • purslane
  • amaranth

So that’s the basics of how to use mycorrhizal inoculant. Any questions? Have you used it before? Let me know below.

Update: About 2 1/2 years after writing this, I decided to start selling the mycorrhizal inoculant I use. You can learn more about it here.

33 Comments

  1. Bill on August 6, 2011 at 6:22 pm

    Great presentation Phil! I recently bought a product called ‘Myke’ (or Mike?) but it seemed more like peat moss. I am wondering if this brand has only a little bit of actual Mycorrhizal fungi with lots of peat moss as a filler? 

    • Phil on August 6, 2011 at 11:34 pm

      Myke is not bad. The carrier is necessary to help with application, so I don’t think you need to worry about two much filler with that brand.

    • Lynne on January 22, 2012 at 2:49 pm

      Myke is the only commercially available source of micorrhizae in Canada. The spores are nearly invisible to the eye, so they mix it with a sterile “filler” for application purposes. Don’t use it like fertilizer… you only need a couple of spoonfuls to plant a tree. 

  2. shizzoberry on September 11, 2011 at 12:58 am

    should it be used during flowering stage to? or just seedling & veg?Ive been wondering if i should be adding it to my flower nute mix?i have been,& i dont notice any problems but?  what ya think? 

    • Phil on September 12, 2011 at 11:04 am

      If it wasn’t used during planting/seeding, it can be used any time after, including during flowering. There’s no need to use it every time you fertilize, but it doesn’t hurt.

    • Lynne on January 22, 2012 at 3:06 pm

      Keep in mind that mycorrhiza is a living organism. It only grows when it makes contact with plant roots. The fungi provides the plant with nutrients, and the plant provides the fungi with carbohydrates from photosynthesis (since the fungi cannot photosynthesise.)Don’t waste your money by applying it like a fertilizer. It must be applied to the roots. For established perennials, trees and shrubs you may cause damage by trying to apply it at the root zone; disturbing the soil will kill any fungi that are already growing there. For annuals and vegetables, it”s best to apply it at planting time when the roots are already exposed. 

      • Phil on January 23, 2012 at 12:52 pm

        You’re right Lynne, but the very fine powders can be watered in to established gardens unless your soil is very compacted – no soil disturbance necessary.

  3. Mike on December 10, 2011 at 4:41 pm

    Phil, I have been using Myke when planting outside with great results, is the fungi effective in a aquaponics set up where there is no soil in the growing media (after germination). Also your thoughts on aquaponics, any good sites about set up and equipment etc.?

  4. Allen on February 19, 2012 at 7:48 pm

    Hi Phil, You suggest here – ( http://www.smilinggardener.com… ) – that Plant Success Granular Mycorhizae Inoculant is probably okay since you’ve determined who manufactured the mycorrhizal spores. What I am unclear on is how to apply this since it is not a powder. I am guessing I need to till it in. Is that accurate?What would the application rate be for applying to the soil before planting if you have any ideas? Can’t tell from the amazon listing and need to determine how much to buy.We are in SC and will plant a wide variety of vegetables from seed. Doesn’t seem as though I’ll be able to assure contact with each seed using the soil-mixing method and seems like I’ll need to use more product. Nevertheless I don’t see any other options on Amazon and I’m also not finding any organic gardening centers in this area.What are your thoughts if you would?Thanks!Allen

    • Phil on February 20, 2012 at 5:51 pm

      Hi Allen, if you’re applying during seeding, you could incorporate it into the soil or it might be much easier just to mix it with the seed before seeding. You don’t need to have it contact each seed, just be in the general vicinity in the soil. The roots will find it, so there’s really nothing to worry about there. Go to plant-success.com for application rates for that particular brand.

    • Phil on February 20, 2012 at 6:02 pm

      Hi Allen, if you’re applying during seeding, you could incorporate it into the soil or it might be much easier just to mix it with the seed before seeding. You don’t need to have it contact each seed, just be in the general vicinity in the soil. The roots will find it, so there’s really nothing to worry about there. Go to plant-success.com for application rates for that particular brand.

  5. Elias on April 16, 2012 at 7:31 am

    Hi Phil,I’m very much new to this, so forgive me if this is a silly question… You list some plants which do not form relationships with mycorrhizal fungi. Is that to say they don’t care wether or not they are there, or would they benefit from not having it in the soil at all?

    • Phil on April 16, 2012 at 12:28 pm

      Hi Elias, I can’t say there is no effect at all, but basically, it doesn’t matter because they don’t form a relationship with the fungi – so the fungi don’t substantially help them or hurt them.

  6. Tulsi on August 4, 2012 at 8:54 pm

    Hi Phil,Thanks for the great info.  I have an allotment garden since last summer, and don’t know what the former gardeners planted where.  Last year I lost all my tomatoes except a ‘wild tomato’ to late blight.  Now all my tomato plants again have late blight (at least i got to harvest a few first this summer).  All the neighboring plots also have it, including some who have their tomatoes in ‘houses’.  I was thinking of giving up on tomatoes… until I heard of a product containing ‘Trichoderma harzianum’ which is meant to form a symbiotic relationship with tomatoes and prevent late blight.  However it costs 70 euro, and comes only in a 1 kilo package (at least what i can find in germany…)Have you heard of or have any experience with this fungus? The company that sells it says it needs to be reapplied every year – but most germans turn their soil every year.  Do some fungus’s get killed by winter?

    • Phil on August 6, 2012 at 7:50 pm

      Trichoderma can be useful, but I would take more of a holistic approach instead of just adding one species. If you can get your soil healthy, the blight won’t cause problems. Quality compost will help, and a straw mulch, as well as regular applications of aerated compost tea during blight season. And then – it’s too advanced to explain here, but I would test your soil with a good organically-minded lab and get the soil fertility balanced out. Blight is partially a phosphorus deficiency in the soil, so if you can get your hands on some rock phosphate, that will help.

  7. Lexi Rodrigo on October 24, 2012 at 4:10 pm

    Hi Phil, Do mycorrhizal fungi form relationships with weeds?

    • Phil on November 2, 2012 at 4:28 pm

      Actually many weeds do not form the relationship, so they often thrive on mycorrhizal-deficient soils when the plants you’re trying to grow don’t.

  8. Mukluk on December 1, 2012 at 2:06 am

    Hi Phil,I have been trying to find out for some time but no one seems to know the answers. If I innoculate a perennial vegetable such as garlic with mychorizae, is it likely that the fungi will survive when I dig up the bulbs dry them and then grow again when I replant the bulb? If I post the bulbs to a friend is it likely that the fungi symbionts will also be posted with the bulb and innoculate the garden it is planted into?Also, will sulphur damage mycorrhizae? I have a pH issue and am undecided if I should use sulphur or not for fear of damaging the fragile fungi in the soil.

    • Phil on December 4, 2012 at 1:24 pm

      My understanding is that the mycorrhizal fungi may very well survive when dug up/replanted and when sent to your friend. There could be some dormant propagules that will break dormancy when the plant is actively growing again. Of course, it probably depends on the health of the fungi in the first place, and certainly on the environmental conditions during storage/transit.Sulfur can harm most microorganisms. You don’t want to manage pH anyway. Get a good, organic soil test done by a lab and manage the nutrients. If indeed you need sulfur and want to take it easier on your microbes, don’t apply to much. It may be best to apply no more than 2 pounds per 1000 square feet, and then focus on improving the biology to make that sulfur as bioavailable as possible.

      • Mukluk on December 6, 2012 at 4:32 am

        Thanks for the info Phil. I thought that may be the case but have had no one to ask since I studied mycology over ten years ago. The difference mychorizae makes is amazing, especially when it is applied after a bush fire has been through.Do you buy inoculate each year or is there some way that you can make your own innoculant? Would it be possible to innoculate a potted plant and trim the roots each year to use to other gardens? I assume that if this worked you would use the root trimmings strait away and would not store them.

        • Phil on December 12, 2012 at 4:25 pm

          You can make your own inoculant, but it’s a bit of work to do well and I’ve always been happy to just buy it every year or 2. It is possible to inoculate a potted plant and use the roots (that’s how some inoculants are made), but unless you’re lab testing or using a microscope, you don’t really know how well those fungi are thriving in there. It would be a fun experiment, but to ensure results, I buy.

  9. Brian Michael Shea on March 22, 2013 at 1:52 am

    I was wondering, is there a difference in fungi that is used according to climate? I mean will the same product work in South Florida(where I live) as in Canada, or anywhere else for that matter? Or are different brands with different species of fungi used for different places?Also, if I were to use an innoculant on a newly made bed, would I just broadcast it and work it into the soil, or should it be applied to each plant as it is planted?

    • Phil on March 25, 2013 at 1:35 pm

      Many of the main fungi are prevalent all over the world, so the same product does work everywhere.If you are planting very densely, you could work it into the whole soil, but I prefer applying to each plant, and mixing it with seeds. Saves a lot of product.

  10. tom on August 10, 2013 at 2:18 pm

    Would you also use it in planting garlic?. Powder each clove as you plant it?

    • Phil on August 12, 2013 at 3:36 pm

      Yes, but I’d just put the cloves in a pile and sprinkle the powder on all of them at once. And actually I quickly soak them in a mixture of kelp and/or sea minerals and water first.

  11. Cindy Ethridge on March 13, 2014 at 6:15 pm

    Hi Phil. I am planting in straw bales and buckets this year. Do you think the micorrhizae would still be beneficial ?

    • Phil on March 13, 2014 at 7:24 pm

      Absolutely Cindy, perhaps even more so.

  12. Gary on July 31, 2014 at 4:53 am

    Hello Phil… I live on Oahu in Hawaii. Everything that is sold here is shipped in containers on a barge and the container can get very hot in the sun. Can the Mycorrhizal spores survive in heat for a few days of shipping or am I buying a dead product?

    • Phil on August 3, 2014 at 7:14 pm

      Hi Gary, I wrote the guy who’s in charge of growing my mycorrhizal spores and here’s what he said. Hope it helps:”Hi Phil, the spores are pretty durable. The threshold is around 140 f when they are damaged. I would think they are ok on the barge, although I am not sure how hot it gets.”

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