Got this pack of root inoculant for free at a plant expo and was wondering if San Pedro cacti share a mutual bond with the listed species of fungus/bacteria. Also let me know if anyone has had positive results on their cacti from root inoculant! I worry that the rootball always drying out between waterings would kill the beneficial fungi/bacteria?
by Distinct-Ad-7505
8 Comments
The soil will likely not support any fungi, there’s not enough organics in most cactus soil.
I use Great White Mycorrhizae with 2 parts Ocean Forest to 1 part horticultural charcoal. The charcoal acts like a hotel for the Mycorrhizae. All my Trichos are in that mix.
It certainly won’t hurt. Plant Success brand has a good amount of humic acid which essentially makes the nitrogen already in your soil or any liquid fertilizer more available. You’ll likely see a boost from the humic regardless
I used this on some Trichocereus grandiflorus. It seemed to help. The soil was much more organic then my San Pedro’s though.
I use it all the time. It helps root development.
Do it
I use Great White powder with hydroponic growth, but I’m not sure whether the bacteria and mycorrhizal fungi can actually thrive in coco coir and perlite when using mineral nutrients. I also have doubts that a product designed for cannabis will work just as well for a completely different species. My thinking is that perhaps they might at least help prevent the spread of harmful organisms. Maybe I should try a double-blind experiment during my next grow to find out for sure.
When I transplant my roots seem healthier in mixes with mycorrhizae than those without. Lots more fine white root hairs just like you’d see in plants.
I disagree with others saying there’s not enough organics or that it’s too dry to make a difference. Ymmv, and perhaps those people have much more mineral heavy mixes, but trichocereus does really well in mixes with plenty of organics. My mix is 50/50 happy frog/perlite, and I have seen the same mix recommended and used with heavy feeding plants like cannabis.
Trichocereus are pretty heavy feeders as far as cactus go, and don’t need to be put in mineral heavy cactus soil. In fact I think they do better in just regular potting mix with some extra drainage added.
On top of that I can water once a week, about as frequently as any other plants I have grown. Just because the top couple inches of soil dries out does not mean there’s no moisture in the soil (especially deeper down). So at least in my case I don’t think that’s enough for the mycos and microbiology to be killed off. One of the things mycorrhizae is known for is increasing drought resistance in plants. There’s no water in things like great white mycorrhizae when you buy it, so obviously the organisms can survive at least some amount of time without being watered. Once they are applied they are in an active symbiotic exchange with the plants.
Overall I wouldn’t over think it. Everyone is going to have their own opinion, and also factors like price or personal gardening style that affect that opinion. You can always try things out for yourself and see what you think, but it can also be hard to really quantify benefits. It’s not like if you add some mycorrhizae you’ll see a sudden increase in growth like you would adding synthetic nutrients. That doesn’t mean that there’s no effect on the overall health of the soil and plant. It can be hard to notice things like disease or drought resistance because it just looks like your plant is continuing to be healthy.