Anti-fungal foliar spray test of aerated worm compost tea

Aloha Growmies!

I reached a turning point in the test. Yesterday I found some PM and aphids... mostly on Kush#2 (the control), but a little on Kush#1 (the test subject). I decided to spray, so tonight I sprayed a solution of limonene, soap, and peroxide... a new mix I haven't tried yet. I sprayed both plants.**

So I'm thinking tonight's spray has got to be hard on any beneficial bacteria that may have gotten established on the leaf surfaces, on Kush#1. What I'm going to do is make another batch of worm tea, this time with only worm castings and no added nutes. I'll rinse off the plant with plain water tomorrow. When the tea is finished brewing (32 hrs), I'll spray Kush#1 again.

Here's some photos from yesterday and today...

Kush#1 on the left (the test subject), and Kush#2 on the right (the control).
kush1_and_kush2.jpg


Kush#1... looking good, no mold spots. A little bit of PM and some slight sign of bugs.
ckush_plant1.jpg


Kush#1 early flowering.
ckush_early_flower1.jpg


Kush#2 (the control) has this unhappy looking branch... yellowing, necrosis, PM, and aphids. No black mold anywhere on the plant. The orange circle is enlarged in the next photo.
ckush_plant2.jpg

Aphids!
aphids1.jpg



** @Sativa1970 was curious about the pH of my limonene spray. I tested pH and here's what I found...

Rainwater 7.45, +soap 7.70, +limonene 7.76, +more soap 8.43, +peroxide 8.15.​
Ratios: 1/2 gal water, about 3/4 tsp Bronner's peppermint soap, 12 drops pure food grade limonene, 6 fl oz (12 tbsp) 3% peroxide. Maybe I neutralized my peroxide... what do you think?​
 
It will be interesting to see if this new mix works since the old one didn't. I was wondering which of the new ingredients would be most effective between the limonene, H2O2, and Dr Bronner's.

The Dr Bronner's alone should take care of the aphids if that's a strong enough mix.
My usual mix is neem, Bronner's peppermint soap, and water. I didn't want to use that since the plants are in flower. I sometimes add limonene to that mix. By "new mix" I mean without the neem. I also threw in the peroxide, too.

The purpose of this thread, however, is to test the effectiveness of actively aerated compost tea (AACT) to protect the plants from dark mold spots and bud rot. I sprayed the "new mix" as sort of a "reset", due to the presence of the aphids and PM. Now I'll wash the two test plants and start a new batch of compost tea. I also need to clear some weed trees because the greenhouse isn't getting optimum sun.
 
I started a new batch of compost tea tonight. I used about 12 cups of worm compost, and 1 tbsp of solution-grade fulvic acid powder. I am using a new 4 watt air pump, with 2 outputs combined to supply air to one stone. Tonight I ended up using the small, circular airstone that came with the pump. It looks like all these air stones come from China and have the same manufacturing process. The bigger stones seem to always leak big bubbles near the connection point of the tubing, which depletes the pressure to the rest of the stone to produce tiny bubbles.

Here's the new pump, with both outputs connected to a T-fitting, followed by a check valve. The pump is turned up to full power (4 watts).
new_pump1.jpg


Brewing started. The airstone is suspended just above the muck layer at the bottom of the bucket. The tea will be ready on Tuesday morning. The pH of the tea before adding the fulvic acid was 7.84. After fulvic added, 7.68. The rainwater is 7.45. So, the worm compost has almost neutral pH.
compost_tea_brewing1.jpg


This is a Vivosun airstone, which looks exactly like the manufacturing of the Active Aqua stones I already have. I think they are all sourced from China. I got two of these and tried one with the new pump. It leaked a lot of big bubbles close to the nipple, and production of small bubbles over the whole stone was not great.
new_airstone1.jpg


I decided to try stopping the leaks, so I applied aquarium-safe silicone to the whole area that was leaking. I'll try this stone again tomorrow and see if the fix works.
new_airstone_silicone1.jpg
 
I harvested the 2nd batch of compost tea tonight, and double filtered it. The finished tea tested 487 ppm and pH 7.9. I was surprised that the ppm number was so small, but obviously the result of excluding the other nutes from the mix. I was also surprised that the left over sludge was only about 5 cups worth... down from more than 12 cups of worm castings added at the beginning. Next time I'll add more worm castings.

I used the tea straight without diluting, in my 1 gal. pump sprayer. I sprayed all the plants in the veg house and flower house, except for Kush#2 (the control). I sprayed after dark, around 7:30pm. All the plants got fertigated also earlier in the day. Tomorrow I need to cut weeds and weed trees around the flower house, to let in more sunlight.

Re: black mold spots on the underside of leaves... Kush#1 (the test) remains essentially free of mold. Kush#2 (the control) is almost the same. I saw some mold on the two small CBD plants, and the Maui Wowie plant – we'll see if this 2nd application of tea helps. All the plants in the flower house are rapidly developing flowers. This will be the last application of foliar tea for this test.

More surprises... this mod I made to the big airstone didn't work at all. I'm mystified about these stones... they just don't work. The small one that came with the new air pump works well. I'll try one more time with the silicone, on a stone I have that's 1/2 the size of the pictured one. The one pictured... I'm gonna take a hammer to it and see what's inside!
1665556644047.png
 
More surprises... this mod I made to the big airstone didn't work at all. I'm mystified about these stones... they just don't work.
Those stones can sure be finicky. Hope you post a pic of the busted up one. I'd imagine it's just a solid piece of stone with a hole drilled out for the adapter, but maybe not. :hmmmm:
 
Those stones can sure be finicky. Hope you post a pic of the busted up one. I'd imagine it's just a solid piece of stone with a hole drilled out for the adapter, but maybe not. :hmmmm:
Yeah, I'll post a photo.
 
Hey Growmies,

So here's what I have so far... Kush#2 (the control) is showing some black mold on the underside of leaves, while Kush#1 (the test) is showing little to none. Kush#2 is also showing some bug evidence and slight PM, while Kush#1 is basically clean.

I'm not saying that every single leaf on Kush#1 is optimum, but overall, Kush#1 is fairing better than Kush#2. The difference is not huge, but noticeable.

The plants have weeks to go in flower, so I'll give an update in 3 weeks. I will avoid spraying any peroxide on Kush#1 (the test). I may need to spray some peroxide and/or orange oil + soap mixture on Kush#2 (the control), since I still would like to get a harvest from that plant.

Meanwhile, I took a hammer to one of my airstones to see what's inside...

2" x 4" airstone from China, broken in half
1665818894424.png


This confirms a channel down the center. Nonetheless, almost no bubbles came out of the body of this stone when I tried it, even after adding a layer of silicone as shown in the photo in my previous post.

I have one of these large stones left, so I will try again with a thicker layer of silicone right around the base of the nipple and extending onto the stone. I'll let that dry completely, and then test by first soaking the stone in water for 1 hour (recommended on the package they came in).

I also have a 2" x 2" stone, and I'll try the same mod on that one.

happy growing! 🪴
 

@cbdhemp808 Thanks for taking the time to test PH. Was just curious how it would be effected by the oil.​

I am pretty sure you now this but more for anyone reading this as a tutorial in the future. When you spray for pests, start with the under side of the leaves from base of the plant working up the plant. Little beggars run under the leaves and down the stem to protect themselves from "rain".


I have tried scrubbing, boiling, vinegar soaking, high air pressure, and hydrogen peroxide on stones that don't flow even. So far results have been, made no difference or complete destruction. Good luck.
 
I have tried scrubbing, boiling, vinegar soaking, high air pressure, and hydrogen peroxide on stones that don't flow even. So far results have been, made no difference or complete destruction. Good luck.
These are brand new. I have applied silicone on the two remaining stones: 2x4 in and 2x2 in. This time I concentrated the silicone right around the nipple. When it's dry, I will soak the stones in water. Will report findings here.

I'm not saying that every single leaf on Kush#1 is optimum, but overall, Kush#1 is fairing better than Kush#2. The difference is not huge, but noticeable.
The more I observe over time, the more I think there is very little difference. We'll see if there's a difference when it comes to bud rot, which is far more serious than the mold on the underside of leaves. I can generally take care of the mold using peroxide.
 
Well, I wasn't going to post for 3 weeks, but after 1 week here's some interesting developments.

First, to my surprise, the airstones are now working well. The addition of a generous layer of silicone, plus soaking, did the trick. Apparently, soaking for 1 hour would work. I soaked for a couple days.

Some substantial mold on Kush#2 (the control). Nothing comparable on Kush#1 (the test).
kush_control1.jpg


Top bud on Kush#2 (the control).
kush_control_bud.jpg


Top bud on Kush#1 (the test).
kush_test_bud.jpg


Here's the 2x4 inch airstone after today's bubble test. The silicone around the base of the nipple worked well, but I still got some large bubbles just beyond the extent of the silicone. The stone emitted a lot of small bubbles throughout its length. I will let it dry out, and then add more silicone and retest.
airstone1.jpg


Here's the 2x2 inch airstone after today's bubble test. This one had silicone around the base of the nipple, and covering the whole surface to the edge. This stone worked perfectly today.
airstone2.jpg
 
Things are happening fast. It was only Thursday that I posted photos of those top buds with all white stigmas, now the plants are already showing lots of brown stigmas!

I'm also seeing some signs of bud rot, but haven't taken a close look yet.
 
Not sure if it's your experience but I find sprays will often brown the pistils regardless of when they're applied.
I don't think this is due to the sprays.
 
Greetings Growmies,

Before tonight's big update, check this out... crazy fast flowering time... WTF?!

The photos show one of 2 Kush clones, flipped to the flower house at the same time. So, 4 photos below, starting with pre-flower on Sept. 30, and ending with a nearly finished bud on Oct. 24 ?! Now... to be fair, the trichomes aren't ready yet... there's still a lot of clear ones. HOWEVER, I've got a Maui Wowie and 2 CBD phenos flipped around THE SAME TIME, and they are DONE!

Sept. 30 - Oct. 24 = 3 weeks, 3 days.

Can anyone explain why my plants had a 25-day flowering phase? What I've recorded in the past is 5-7 weeks.

Kush on Sept. 30 - pre-flower
1666680017682.png


A week later...

Kush Oct. 8 - early flower

1666680177417.png


12 days later...

Kush Oct. 20

1666680275812.png


this transition is mind-blowing... 4 days?!

Kush Oct. 24

1666680405709.png
 
And now we return to our regularly scheduled programming...

Things are happening fast. It was only Thursday that I posted photos of those top buds with all white stigmas, now the plants are already showing lots of brown stigmas!

I'm also seeing some signs of bud rot, but haven't taken a close look yet.
After a close look, I found that both Kush#1 (the test) and Kush#2 (the control), had almost the same amount of bud rot starting to develop. I clipped out the rot and made separate piles for each plant, to compare the amount. I then sprayed down both plants well with peroxide solution. These plants are at that nasty juncture between trichomes not ready and vulnerable to widespread bud rot. I'll need to harvest early.

Overall test results: 1) slight improvement to inhibit black mold formation on underside of leaves, 2) slight improvement to inhibit bud rot. Either my compost tea was lacking sufficient microbes, or I needed more foliar applications (maybe 5 instead of 2), or 3) compost tea foliar spray doesn't really work to prevent mold and bud rot.

Today's photos...

Piles of bud rot clipped out of both Kush plants. Kush#1 (LEFT; the test). Kush#2 (RIGHT; the control).
rot_compare1.jpg


Top cola, Kush#2 (the control)
kush2_top_bud1.jpg


Top cola, Kush#1 (the test)
kush1_top_bud1.jpg


Kush bud close-up
kush_flower1.jpg


CBD pheno. Two of these clones also got the 2 foliar sprays of compost tea. No bud rot visible, and they are ready to harvest.
cbd_pheno1.jpg


Top bud, CBD pheno
cbd18_bud1.jpg


The Maui Wowie, accented against a colorized background. I see very little bud rot on this plant, which is typical for this pheno.
maui_wowie1.jpg
 
Can anyone explain why my plants had a 25-day flowering phase? What I've recorded in the past is 5-7 weeks.
Did you add malted barley to them? Coot says it speeds up harvest by 15-20%.

Overall test results: 1) slight improvement to inhibit black mold formation on underside of leaves, 2) slight improvement to inhibit bud rot. Either my compost tea was lacking sufficient microbes, or I needed more foliar applications (maybe 5 instead of 2), or 3) compost tea foliar spray doesn't really work to prevent mold and bud rot.
There are reports of others having success, so maybe tweak it next round. @Bode uses microbes from leaf mold and I believe he sprays weekly, and @danishoes21 uses a variety of different inputs like willow.

Not sure if you need different microbes or more frequency. Good test results though for the knowledge bank. Maybe post them up in the Mold vs. Microbe thread?
 
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