Limiting Phosphorus To Assure Better Mycorrhizael Population

[jumpincactus]

The title is pretty clear, I have been doing extensive research on the beloved mycorrhizae in living soil and have found some data that would support that it is important in the planting of seedlings and the use of mycorrhizae inoculations to keep phosphorus levels low during early vegetative periods of plants.

Early veg is the time you want to have great conditions so the mycelium and hyphae have a chance to establish a strong network for better nutrient uptake from the rhizosphere. There have been studies that show that higher levels of phosphorus early in the inoculation period is actually detrimental to the delicate network we are trying to create.

There are also further studies and data that would support that we as farmers may also be adding more phosphorus than our plants really need. Hre is a quote from 1 site I found .


"According to the University of South Florida IFAS Extension, phosphorus will accumulate to toxic levels when applied as often as nitrogen and potassium. Many other extension agencies concur and suggest alternating fertilizer applications between one with no phosphorus and one with low levels of NPK in either equal amounts or at a

3-1-2 ratio. Phosphorus buildup is caused by heavy use of inorganic fertilizers or the use of composts or manures that are heavy in this element. If soil test indicates that your soil has too much phosphorus, you may have to monitor anything you use for its phosphorus levels.

So, it’s time to throw out the bloom boosting fertilizers with their high phosphorus levels. Any synthetic fertilizer with a high middle number (P) is going to overload your soil with phosphorus. As summer progresses and the leaves of your plants bushes turn yellow, you may be tempted to add something to the soil, such as iron or magnesium (Su-Po-Mag). By doing this, without testing your soil, you may end up worsening the problem."

"Phosphorus Fertility Phosphorus fertilizer can inhibit mycorrhizal colonization and growth. The benefits of AMF are greatest in systems where soil test P is low. As plant available soil phosphorus levels increases the plant tissue phosphorous increases and the plant carbon investment in mycorrhizae is not economically beneficial to the plant (Grant 2005). Encouragement of mycorrhizal symbiosis may increase early uptake of phosphorus, improving crop yield potential without starter P-fertilizer applications (Grant et al., 2005). "


http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.419.4796&rep=rep1&type=pdf
https://www.certifiedcropadviser.or...tified/education/self-study/exam-pdfs/197.pdf



These links are but a few that support the claim to lower P levels increase colonization.

 

[MGRox]

Good post and subject matter Jumpin!!! I know Capulator has mentioned about the myco liking low P in the past. Without looking it up I think he mentioned somewhere around 5-10 ppm.

However, one thing I've NOT gotten answered (but really would like to know), is to whether this relates to: Inactive P, Available P or Active P. As they are all 3 different and all makeup the "phosphorus pool". My supposition from testing would be 5-10ppm of "Active" P.

I guess also I believe; the 3-1-2 they make mention of is a % ratio and not NPK. I.e. 24-8-16 % not 120 - 40 - 80 ppms.

 

[jumpincactus]

You are correct bioavaible P not the P that can get locked up in the soil.

 

[EyeC]

Extracting and transporting "locked" phosphorus in soil to areas where it is needed are some of the more important functions mycchorizae do. :)
Great links and thanks for sharing @jumpincactus

 

[Ned Kelly]

Good info cactus cheers

 

[pugliese63]

Thanks for the links. I lowered my total nutrient EC by about 35% to 1.3 over the last year and have seen very positive results. Phosphorus is readily and easily available in soilless mediums. I use ACT as well as mychorrizae and believe they are much more effective with a lower nutrient program.
I love reading this type of info. Understanding the fundamentals is key to ultimate performance.

 

[john martin]

Potter's Gold soil out of Michigan takes this approach.

"4. I'm not surprised at your reaction to the lab analysis, and for all the misinterpretation and confusion it generated I regret ever having put it on my website. My horticultural library is extensive, and coupled with 28 years of growing & consulting experience provides justification for both target pH (organic container soils) and nutrient balance. Phosphorus supplementation effects pre-bloom through bud set are well documented, but nutrient marketing is powerful and has been effectively coupled with cute artwork and rammed down growers throats. The biggest irony is that the benefit of mycorrhizal fungi is totally misunderstood in growing substrates flooded with excessive P, yet has become another source of exploitation. "



I really like this soil compared to the Roots Original I was running, but am now trying out the Nectar #4 soil.

 

[ShroomKing]

Great info!

 

[jumpincactus]

Extracting and transporting "locked" phosphorus in soil to areas where it is needed are some of the more important functions mycchorizae do. :)
Great links and thanks for sharing @jumpincactus

Yup the mikes can process it it even when its locked up. God Bless the herd!!!

 

[jumpincactus]

Lichen can actually chew thru rock. The world around us and under our feet is magical!!

 

[GrwrGoneWild]

Interesting, could one say that Myco and synthetic feed programs generally do not work well together and one should switch to natural inputs altogether?, if one were to truly take advantage of the symbyotic nature of fungi, like trichoderma.. or beneficials. It seems like synthetics dont mix well with microlife and could supress the specific action we're looking for.

If you reference jeff lowenfells book "teaming with microbes" and take into consideration that cannabis is a fast growing annual, I would say bacteria could be more important than fungi.

 

[leadsled]

Good article, another reason to test your soil and use non-toxic farming techniques.
Soil analysts that respect the biology shoot for 70-75ppm phosphorus.
Forms of synthetic phosphorus get locked up once it hits your soil and are detrimental to the life of the soil.

 

[MJ Indicator]

I can't outright agree that lowering phosphate is an answer to energy efficiency, especially during establishment and possibly late in bloom. Energy efficiency depends on transport, sulfur, boron and silicon being the prerequisite, followed by cal/mag and phosphorous.

So we know the plant's looking for it and most certainly uses it. I concede fungi will have a rough go at it if choked by phosphates, but I feel a reasonable answer is to allow beneficials to establish themselves in a more inert mix then introduce this to the general soil which has one's desired phosphorous. This type of nesting might not crush fungi in their relationship with early establishment, but I do believe phosphorous is crucial to vegetation.

 

[MJ Indicator]

If you reference jeff lowenfells book "teaming with microbes" and take into consideration that cannabis is a fast growing annual, I would say bacteria could be more important than fungi.

Although I'm still on the fence in regards to current or accepted taxonomy of cannabis, I'm a proponent of bokashi. I can't say the effects of EM-1 as a tea are hindered or rendered ineffective when introduced in a soil with balanced or even slightly jacked phosphorous. However, the old-school mentality of throwing phosphate mindlessly at plants just because "they like it" is misinformed.

 

[GrwrGoneWild]

Although I'm still on the fence in regards to current or accepted taxonomy of cannabis, I'm a proponent of bokashi. I can't say the effects of EM-1 as a tea are hindered or rendered ineffective when introduced in a soil with balanced or even slightly jacked phosphorous. However, the old-school mentality of throwing phosphate mindlessly at plants just because "they like it" is misinformed.

Not sure what you are suggesting with the taxonomy of cannabis, most of us are running hybrids with a 30-90 day harvest time.

Bokashi is an interesting thing, I'm still on the fence on it.. EM or fermented aerobic composts tend to be a lactobacillus dominant culture,.. however EM can be "brewed" like AACT, I wouldn't overapply EM, in higher doses according to the studies it could supress other bacteria cultures. Anyways, I lean to the more traditional versions of inoculations, like compost teas that are freebies at garden centers, if one wants to use a waterborne inoculation.

My understanding is that P & K tends to be less available in an outdoor garden environment depending on season. I would guess thats where the flower boosters have come from in the ornamental flower world. Not saying it doesn't work for cannabis but in an indoor soil culture, it seems to be overkill
Many of use are using these very rich soils, and some still insist on using these PK bombs. Its not necessary in my opinion, if we have good microbial and fungal activity, there should be plenty of PK for the plant.

 

[MJ Indicator]

Not sure what you are suggesting with the taxonomy of cannabis, most of us are running hybrids with a 30-90 day harvest time.

My understanding is that P & K tends to be less available in an outdoor garden environment depending on season. I would guess thats where the flower boosters have come from in the ornamental flower world. Not saying it doesn't work for cannabis but in an indoor soil culture, it seems to be overkill

The myriad classification of cannabis; annual vs. perennial, woody vs. weed, broad leaf vs. narrow and so on. The science end of this doesn't consider climate, substrate, grower technique etc. I'm just saying its fun to debate difference to deepen knowledge and that I can't wholly agree its annual by default. For crop purposes sure, then again bonsai cannabis and ornamental cannabis are acquired tastes or maybe odd endeavours. And yes soil indoor with current phosphate trends its certainly overkill, for the most part cannabis growers are still trying to shake habits born mid-century and into the 70's. Case in point blue fertilizer, no offense to hydrangea fans.

 

[GrwrGoneWild]

Curious, why would cannabis sativa/indica/rudy hybrids and land races not be considered annuals?..

I thought bonzai cannabis was common, I like to keep mother plants this way.

The lilacs do like the blue stuff :).. But dont want to hurt them with junk food.

 

[MJ Indicator]

I don't want to sidetrack the thread with the annual debate, but there is plenty of intelligent banter on the internet regarding cannabis classification. Lets just say I feel its more special than its crop-minded denotation, dwarfism notwithstanding.

 

[GrwrGoneWild]

I think its a good question to ask if one thinks its an annual or otherwise, I would move my soil culture to be bacterial or fungal dominant depending on if its annual or otherwise. The relatively short lifespan of cannabis in the wild would lead me to favor soils with more bacterial activity.. Im not trying to exclude fungi from the microherd, but the typical tea treatments dont have a heavy emphasis on fungal activity.. Those are typically used on perennials or even trees.

 

[Papa Indica]

You guys are obviously far more educated on the subject than I am but, I thought I'd throw a little story into the mix. As I'm sure most of you know, phosphorous is non-flammable. In one of my earliest grows I way over did the P, I'm sure other factors were at play too but, when I tried to smoke the buds from that plant they would not burn. It was the craziest thing, I know they were dry, they just refused to be put ablaze.