Mycorrhizae?

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fanaticactus
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Mycorrhizae?

Post by fanaticactus »

I was just looking on Amazon for some horticultural pumice for the planting medium for my cacti. I'll need more soon. I've always ordered plain old pumice. But now I see a product which has 5 stars from practically everyone who has used it. It has everything I usually mix into my soil and, in addition, has 'mycorrhizae'--fungi organisms. In all the years I've been visiting this CactiGuide section on cultivation, I've never seen anyone mention this. I suppose because it's not a major additive. Is it naturally occurring? People seem to love this particular mix for both cactus gardens and in pots. I'm assuming 'mycorrhizae' is beneficial, not harmful in any way. Will it eventually rot? Any reactions from our readers?
Catch a falling star--but don't try it with a cactus!
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toadstar
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Re: Mycorrhizae?

Post by toadstar »

It's probably just some marketing babble. You'll find at least some sort fungi in just about any potting soil or mix. They're ubiquitous in the environment. Unless it's been gamma irradiated, of course.
fanaticactus
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Re: Mycorrhizae?

Post by fanaticactus »

I was not aware that it may just be a fancy name for something that most packaged planting media contain. That would make sense since it's mainly pumice, but this odd-looking word may be just used to set this product aside from others and make it sound more 'scientifically' advanced. At least it's good to know it's not potentially harmful to cacti.
Catch a falling star--but don't try it with a cactus!
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greenknight
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Re: Mycorrhizae?

Post by greenknight »

Mycorrhizal fungi are very valuable for plants, but most natural soils contain plenty. Inoculating soil-less mixes with mycorrhizae does make sense. Since not all fungi are beneficial, there is some logic to inoculating any mix with known good strains, as they can crowd out or (in the case of Trichoderma) actively attack pathogenic fungi.

Mycorrhizae colonize plant roots and grow along with the plant. How long they last in unused potting mix I don't know.

Trichoderma has also been shown to improve germination of Opuntia seeds. Inoculating seedling mix after it's been pasteurized might be helpful in preventing rot as well as possibly enhancing germination - but for that you'd need to purchase inoculant, not pre-inoculated soil.
Spence :mrgreen:
fanaticactus
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Re: Mycorrhizae?

Post by fanaticactus »

This is good information, Spence. Sounds like this company knows what it's doing for providing for the growing needs of cacti. The 5-star reviews by the purchasers of the product (not sure if I can mention the brand name here) are also very encouraging. It's a complete mix, and with Amazon's free shipping I end up getting more product than plain pumice plus shipping would cost through eBay.
Catch a falling star--but don't try it with a cactus!
DaveW
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Re: Mycorrhizae?

Post by DaveW »

It was discussed here:-

https://cactiguide.com/forum/viewtopic.php?f=25&t=31171

How did your experiment eventually work out Spence?

Obviously it depends whether the Mycorrhizae contained are appropriate for the Cactaceae. Rootgrow has been available in most UK Garden Centres for quite a few years, but I did not notice much difference when I used it.

http://www.rootgrow.co.uk/mycorrhizal-fungi.html
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greenknight
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Re: Mycorrhizae?

Post by greenknight »

DaveW wrote: How did your experiment eventually work out Spence?
They've all done well, the ones that were inoculated may have done a little better. They're due for repotting now, when I do that I'll take pictures and post an update.
Spence :mrgreen:
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