Automated Foliar Feed Idea

[Legallyflying]

Hey Gang
So I was posting on a thread on how to raise humidity using the little misters that they sell at big box stores. They are tiny and connect together using 1/4 tubing.

Anyways, we do a fair amount of foliar spraying at different times but it's mostly kelp extract, beneficials, and a humic acid extract called liquid gold...which BTW is one of the most impressive nutes I have used.

Anywho.. The new space is twin 25 x 35 flower rooms. Caged DWC trees with very bare bulb. It bangs out the buds but it is an absolutely nightmare in there to move around. It's commando world at its finest( or worst)

So I was thinking..if we installed a couple rows of misters we could foliar right before lights on by just turning a pump on.

Now I realize it won't be as effective as using the big fogger machine but try as I might, foliar feeding gets skipped as its such a hassle to move around.

The big question howevr is this...do you have to wet the stomata on the bottom in order for to it be absorbed? Benficials the answer is no, but what about the humic acid?

Anyone with a little advanced plant physiology knowledge that could shed some light on this would be greatly appreciated.

 

[straincreation]

A majority of the stomatas is in thre under side of the leafs, in order for this to be efficient there would need to be some mister down low to coat the bottom of the leaves.
If only they had a mini version of the lawn sprinklers that pivot back and forth. While having misters instead. I think it would be ideal i also think if you put your mind to it you can DIY.
Interesting concept sounds like it would work great if the under side of the leafs were coated. Somehow.

Again good post.
happy farmin

 

[Legallyflying]

Thanks for the input. So, like most things I have learned about weed growing, I turned to google scholar. Found some interesting research papers and what not about the role of stomata. And then a light clicked on in my head. There is such a high negative pressure at the stomata entrance and it is Sooo incredibly tiny, that nutrient would have a very high time actually passing through the stomata. This was eluded to in several of the papers. Here is a quote from one of the better ones...


There are two possible channels for penetration of foliar-applied compounds into the leaf before they can produce a response. One is through the stomata and the other is through the external cuticle. It is generally accepted that most nutrient uptake occurs through the cuticle, but solutes can also gain entry into the leaf indirectly through the stomata. However, there is some controversy about the importance of stomatal penetration into the interior of the leaf. Prior to 1970 there was considerable debate about the importance of stomatal uptake of foliar-applied nutrients. This debate largely subsided since it was shown that it was not possible for a water droplet to enter the stomata of leaves of higher plants due to the surface tension of water, the hydrophobicity of leaf surfaces, and the geometry of the stomate. Furthermore, ion uptake rates from foliar sprays are usually higher at night, when the stomata are closed, than during the day, when the stomata are open. Recently, new evidence was presented for the uptake of large anions through stomata indicating that stomata might indeed represent a possible pathway through which a limited amount of the nutrient might gain entry into the leaf. Generally, however, it is assumed that all liquid uptake of water and dissolved substances occurs exclusively through the leaf cuticle provided there are no surfactants present. Surfactants in agrochemical sprays typically provide surface tensions of about 30 Mn m-1, which would usually not be sufficient to enable stomata to be infiltrated. However, organosilicone surfactants can reduce aqueous surface tensions to about 20 Mn m-1 and allow nutrient entry via the stomates. Furthermore, stomatal penetration can occur only in the brief period after application while spray deposits remain liquid. Thereafter cuticle penetration remains the sole pathway of uptake. In cotton, it is unlikely that direct penetration of solutes from the leaf surface through open stomata into the leaf tissue plays an important role, because cotton has pronounced stomatal ledges that partly cover the mature stomate, as well as an internal cuticular layer which extends through the stomatal pore and partially covers the mesophyl cells in the sub-stomatal cavity closest to the stomate. The cuticle is generally considered to be the rate-limiting step in the overall process of foliar penetration.


*from. Foliar fertilization: mechanisms and magnitude of nutrient uptake. 2009


Anyways, it seems to me that perhaps all this talk about having to spray nutrients in the stomata is absolutely wrong. It is just one of those things that "stoners think" for lack of a better description. Dude there is holes in the leaves...things must be absorbed through the holes. Plus, cannabis doesn't have a particular thick dermis.


Anyways..maybe this should be moved to the fertilizer section? I just way geek out in this stuff. I want to KNOW how things work, not just that they do. But if you want to watch a pretty damn cool video about plants and physics and stomata...

Then check this shit out. It's cool to be smart people...

 

[Seamaiden]

LMFAO! You found ze paper.

I think it's a great idea, myself, and I bet the plants would absolutely LOVE it.

Hey Gang
So I was posting on a thread on how to raise humidity using the little misters that they sell at big box stores. They are tiny and connect together using 1/4 tubing.

Anyways, we do a fair amount of foliar spraying at different times but it's mostly kelp extract, beneficials, and a humic acid extract called liquid gold...which BTW is one of the most impressive nutes I have used.

Anywho.. The new space is twin 25 x 35 flower rooms. Caged DWC trees with very bare bulb. It bangs out the buds but it is an absolutely nightmare in there to move around. It's commando world at its finest( or worst)

So I was thinking..if we installed a couple rows of misters we could foliar right before lights on by just turning a pump on.

Now I realize it won't be as effective as using the big fogger machine but try as I might, foliar feeding gets skipped as its such a hassle to move around.

The big question howevr is this...do you have to wet the stomata on the bottom in order for to it be absorbed? Benficials the answer is no, but what about the humic acid?

Anyone with a little advanced plant physiology knowledge that could shed some light on this would be greatly appreciated.

I need to find it, but I swear I recently read a paper that discussed nutrients moving through laminar/cellular walls, irrespective of stomata function or location.

 

[Legallyflying]

The effect of foliar application of fulvic acid on water use, nutrient uptake and yield in wheat

X Xudan
Australian Journal of Agricultural Research 37(4) 343 - 350
Published: 1986

Abstract

The effect of foliar application of fulvic acid (FA) on water use, nutrient uptake and yield in wheat was studied in pot experiments and in field trials. FA reduced the stomatal conductance of well-watered plants in pots from ~0.80 to ~0.25 cm s-1. The stomatal conductance of control plants fell continuously from ~0.85 m s-1 to almost zero over a 9-day drying cycle. Plants sprayed with FA at the beginning of the cycle maintained a stomatal conductance of ~0.30 cm s-1 for the whole period. Spraying with FA resulted in a higher level of chlorophyll in the leaves and a greater uptake of 32P by the roots. When droughted at ear-development stage, grain yield was depressed by 30%. Spraying with FA increased the yield of droughted plants to 97% of the irrigated controls. Field trials in North China demonstrated that when FA was used to decrease the water stress or the stress imposed by hot, dry winds during ear development, grain yield increased by 7.3-18.0%.


Full text doi:10.1071/AR9860343

© CSIRO 1986

 

[GR33NL3AF]

I foliar with Kelp, Amino's and Bio Ag's Ful Power very often, I also use a couple different products like Saturator so I only need to spray the tops of the plants. Very helpful.

My company just got their hands on a micro-fogger that can be dialed all the way down to .5 microns, it's incredible, 0nly need 30 PSI to push it. Biological's have been scoped after sprayed with this and still very active. Video coming soon.

 

[Legallyflying]

We have one of those huge foggers. It's pretty money..thing draws 7 amps!

Anyways, it seems to me that you don't need to spray the underside of the leaves so for the $100 it will cost to set up the system we are going to give it a go.

We use cocowet as a surfactant. Works pretty well...very low surface tension and is cheap as hell.

I'll post a picture when it's done but that is going to be at least a month

 

[We Solidarity]

@Legallyflying that seems pretty dangerous, idk if you've ever been to socal but the morning fog is the biggest crop killer down there. If you have any mold issues (including building molds) they are going to be amplified by a million...the humidifier foggers are def the way to go, just make sure they're not pointed directly at plants and disperse in open air.

I've had sprayers over cutting trays that worked real well, sprayed two times a day for a minute and a half, 800 clones in a 4x4 with a 400w MH overhead. Some clones damped off but for the amount of work put in it was by far the easiest and most efficient clone technique I've ever used. I just don't have a need for 500+ cuttings on the regular otherwise I'd always rock that system.

 

[Legallyflying]

Thanks for the tip solidarity. I figured that we would spray maybe 30 minutes before lights on and never within the last couple of weeks.

We haven't had too much problem with mold even though it is in the PNW. We spray in early veg with eagle 20.