soil-media I Need to Update Prior Advice I Gave!!

[NJChilehead]

I have to update everyone who I've discussed soil recipes with! A recipe that I used for potted figs included some pine bark mini-nuggets, for moisture retention and aeration. I extrapolated that to potentially using it in larger grow bags for peppers, and did so last year with no effect. I passed this along to others on here at one point or another (can't remember the exact thread). I was just on a gardening page and someone mentioned phytotoxicity of pine bark. Well I looked a little further into it, and studies have shown that pine bark can be potentially phytotoxic to nightshades like peppers and tomatoes. I personally didn't see any effects, but mine may have been aged enough so that the compounds causing phytotoxicity may have already started to break down. Also, I don't know how much impact a small amount could have, but I think it's worth looking into!

Has anyone else ever read/heard anything about phytotoxicity of pine bark nuggets and nightshades?

 

[danish]

Sounds allelopathic, in which case it's specifically a green wood issue, which is already full of issues for a growing medium. The other thing it could be is a metals issue but it's unclear just how much toxicity that could cause, possibly an issue from years of build up from trees pulling metals from saturated ground. Did this 'someone' on a gardening page happen to point to a specific scientific paper? I once saw someone on a gardening page highly recommend the tiny tomatoes that potato plants make for a salad.

 

[ShogunPeppers]

N

I have to update everyone who I've discussed soil recipes with! A recipe that I used for potted figs included some pine bark mini-nuggets, for moisture retention and aeration. I extrapolated that to potentially using it in larger grow bags for peppers, and did so last year with no effect. I passed this along to others on here at one point or another (can't remember the exact thread). I was just on a gardening page and someone mentioned phytotoxicity of pine bark. Well I looked a little further into it, and studies have shown that pine bark can be potentially phytotoxic to nightshades like peppers and tomatoes. I personally didn't see any effects, but mine may have been aged enough so that the compounds causing phytotoxicity may have already started to break down. Also, I don't know how much impact a small amount could have, but I think it's worth looking into!

Has anyone else ever read/heard anything about phytotoxicity of pine bark nuggets and nightshades?

No, I stay away from recipes and use straight composted manure in my garden

 

[NJChilehead]

Sounds allelopathic, in which case it's specifically a green wood issue, which is already full of issues for a growing medium.

I agree, which is why I included the quote below:

I personally didn't see any effects, but mine may have been aged enough so that the compounds causing phytotoxicity may have already started to break down.

Regarding literature, I did look into the topic a bit before posting the above. Here's an example of an article that I found that supported the potential phytotoxicity in nightshades, specifically tomatoes: https://woodsubstrates.cals.ncsu.edu/wp-content/uploads/sites/147/2020/12/56-popular-press.pdf. While I agree that any phytotoxicity is likely due to secondary metabolites in green wood, one reservation that someone could potentially have is not knowing how much residual remains after the aging process is considered complete and the pine bark nuggets are sold, and whether those residual compounds (however small in the amount remaining) would cause any retardation in the early stages of growth. That being said, my plants thrived in the medium I used last year, so that's a point of anecdata that points to negligible or nonexistent effects.

 

[NJChilehead]

Addendum: here's the follow up article to the first one, which details the processing of wood substrates and the remaining phytotoxicity (really the lack of): https://www.greenhousemag.com/artic...mitigating-toxicity-in-fresh-wood-substrates/

 

[DementedWelder]

I've heard of it, but I've aso grown tomatoes, tobacco, and chilies next to pine trees and directly in pine bark, needles, and sand with no problems.

 

[stettoman]

I gotta toss my 2 cents, and this is anthropologically anecdotal.

Since I was VERY young, growing up in the coniferous regions of northern and northeast Minnesota, even the blended region of the northwest coniferous/deciduous areas, it was understood by generational farmers that cultivation is unadvised anywhere a stand of pines has been cleared within 15 to 20 years because of the sterility for healthy crops.

I don't know the veracity of this behavior, but I have seen the bare, sterile ground beneath large pines and other evergreens. What I've been told by native people up there was "These trees bleed death below them to protect nutrients to themselves."

Not science per se, but I have never had cause to disbelieve it...

Two cents spent...

 

[JAB Farms]

I've heard of it, but I've aso grown tomatoes, tobacco, and chilies next to pine trees and directly in pine bark, needles, and sand with no problems.

I don't use a bark but like this, I have a TON of Pine trees in the yard. Hence why my soil is so acidic. This is an interesting topic btw...

 

[JAB Farms]

I gotta toss my 2 cents, and this is anthropologically anecdotal.

Since I was VERY young, growing up in the coniferous regions of northern and northeast Minnesota, even the blended region of the northwest coniferous/deciduous areas, it was understood by generational farmers that cultivation is unadvised anywhere a stand of pines has been cleared within 15 to 20 years because of the sterility for healthy crops.

I don't know the veracity of this behavior, but I have seen the bare, sterile ground beneath large pines and other evergreens. What I've been told by native people up there was "These trees bleed death below them to protect nutrients to themselves."

Not science per se, but I have never had cause to disbelieve it...

Two cents spent...

Agreed to an extent... I do have to lime the heck out of my soil and grow clover in off season over the top and have not had issues. Maybe they are far enough away and the fact that I am putting mostly hot peppers out - it doesn't care. Area's where Tomatoes and Cucumbers are going to be, I treat with more lime and gypsum to help.