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.

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Hey guys! It’s Phil from 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.