Care for orchids in charcoal

[Nicolasdperez]

Hello, I recently potted a few of my orchids in charcoal and was wondering if anyone with more experience has advice for care in charcoal. I have done some research and this is what I know so far:

1) charcoal is very porous and will absorb salts. Hence salt based fertilizers should be avoided to prevent salt burn.
1) charcoal should be natural as many bbq charcoals have added chemicals to help with combustibility.

What I am unsure about:

1) does charcoal need to be flushed and if so how often?
2) can the ph of charcoal negatively affect orchids?
3) what are good organic fertilizers to use in charcoal?

I love how accessible and cheap charcoal is so it would be great if someone could help me navigate the intricacies. Thank you for your time

[Shadeflower]

Top Benefits Of Adding Charcoal To Your Potting Medium - Orchideria

[estación seca]

First of all - what charcoal are you talking about? Where would you get it? I don't use it routinely because other things are easier to get here. Horticultural charcoal is usually made by burning wood at a high temperature with very low oxygen, so it winds up being very hard and durable, with little powder. It does not look like most charcoal sold for cooking.

"Salt-based fertilizers' means almost all granular fertilizers sold for plants. You can use them with charcoal as long as you flush the pot with pure water periodically. Charcoal is not much different from LECA or bark in this issue. Anything with small spaces where water can sit and evaporate, rather than running off, has the same issue.

pH is more related to the water/fertilizer you pour in and the water remaining in the pot. I don't think it would matter.

There wouldn't be any better or worse fertilizers to use so long as you use them rationally. I would use the granular fertilizers I use on plants in other media.

Depending on the plant you could top a layer of charcoal with a layer of leaf mold or leaf litter. So long as things kept moist and there were large air spaces inside this potting method works well since it mimics natural conditions for a lot of plants.

[Nicolasdperez]

Originally Posted by estación seca

First of all - what charcoal are you talking about? Where would you get it? I don't use it routinely because other things are easier to get here. Horticultural charcoal is usually made by burning wood at a high temperature with very low oxygen, so it winds up being very hard and durable, with little powder. It does not look like most charcoal sold for cooking.

"Salt-based fertilizers' means almost all granular fertilizers sold for plants. You can use them with charcoal as long as you flush the pot with pure water periodically. Charcoal is not much different from LECA or bark in this issue. Anything with small spaces where water can sit and evaporate, rather than running off, has the same issue.

pH is more related to the water/fertilizer you pour in and the water remaining in the pot. I don't think it would matter.

There wouldn't be any better or worse fertilizers to use so long as you use them rationally. I would use the granular fertilizers I use on plants in other media.

Depending on the plant you could top a layer of charcoal with a layer of leaf mold or leaf litter. So long as things kept moist and there were large air spaces inside this potting method works well since it mimics natural conditions for a lot of plants.

Hello. Currently I am using charcoal that I made myself. I cut the wood from an old tree stump and made in a smoker at over 450 degrees Fahrenheit for about 3 hrs.

Thank you for clarifying about the flushing. By using pure water, do you mean distilled water with no salts or additive or simply water without fertilizer?

Thank you further explaining the salt fertilizers, ph, and using charcoal with leaf litter. All of this was very helpful. Have a good day.

[estación seca]

It will be interesting to see how it works. I think it should.

Yes, periodically flush with rain, distilled or reverse osmosis water, with nothing added. If your tap water quality report from your water utility shows you have low amounts of dissolved solids you can use that - perhaps if it's under 150-200 parts per million or milligrams per liter.

[Ray]

ES is right about the “mineral-trapping” properties.

“Activated” charcoal would be different, as the preparation and creation of it results is millions of ultra-fine fissures and pores that grab and hold stuff. Your homemade charcoal and horticulture charcoal in general have very little activation.

[SADE2020]

I don't, but my mom uses 100% charcoal with Catts and they are amazing. The charcoal is supposed to control bacteria and fungi.

But she uses controlled-release granular fertilizer; nutricote 14 -4-14

The PROS:
- Continuously and precisely releases nutrients, ensuring uniform growth.
- Maintains adequate levels of nutrients in plants, ensuring excellent maintenance.
- Reduces nutrient losses (reducing associated pollution)

The CONS:
She has plants in a tropical climate, with constant watering, actually, the carbon is to support them and to dissolve the fertilizer.

I don't know if it would work the same in other environments.

I personally use charcoal, in the background of all my MIXs and especially with the Catts. I don't have anything 100% charcoal, because I prefer to use a medium that will retain more moisture, especially in winter when I don't water as often. However, this winter I intend to leave them out, not outdoors with rain, but with a high level of humidity and I am considering trying 100% carbon with some.

[estación seca]

Making your own charcoal from tree stumps that need to be removed is a better idea than hauling around bags of medium!

[Nicolasdperez]

Originally Posted by SADE2020

I don't, but my mom uses 100% charcoal with Catts and they are amazing. The charcoal is supposed to control bacteria and fungi.

But she uses controlled-release granular fertilizer; nutricote 14 -4-14

The PROS:
- Continuously and precisely releases nutrients, ensuring uniform growth.
- Maintains adequate levels of nutrients in plants, ensuring excellent maintenance.
- Reduces nutrient losses (reducing associated pollution)

The CONS:
She has plants in a tropical climate, with constant watering, actually, the carbon is to support them and to dissolve the fertilizer.

I don't know if it would work the same in other environments.

I personally use charcoal, in the background of all my MIXs and especially with the Catts. I don't have anything 100% charcoal, because I prefer to use a medium that will retain more moisture, especially in winter when I don't water as often. However, this winter I intend to leave them out, not outdoors with rain, but with a high level of humidity and I am considering trying 100% carbon with some.

Wow! I had no idea about the anti bacterial properties. I know charcoal is very common in humid places, however I started experimenting with it for a potted vanda. Since I am in a dry environment, the charcoal dries up very fast meaning that the roots don’t have time to rot. It should be interesting to see how it goes. Thank you once again for your input.

[K-Sci]

Originally Posted by SADE2020

I don't, but my mom uses 100% charcoal with Catts and they are amazing. The charcoal is supposed to control bacteria and fungi.

How?

-Keith