First grow, plants died overnight!

[JKD]

By hydro roots I think he means without all the little feeder roots off the main roots like you get in soil.

 

[Crooked8]

Oh secondary and tertiary rooting. I guess that does happen a lot less in hydro. I thought he meant the coloration based on the over watering he mentioned. Over watering def causes roots to turn brown and rot.

 

[RetroGrow]

By hydro roots I think he means without all the little feeder roots off the main roots like you get in soil.

Right. He's not hydro, but has "hydro roots", thicker, less fine roots. It's from over watering in soil.

 

[RetroGrow]

Hydro roots? The roots in all my hydro are super white. If they're brown like that in hydro you're in trouble. A slight tan coloration by the END of harvest is still a sign that roots aren't at their potential but is fairly common.

He's in soil, not hydro, hence the color of the roots.

 

[Crooked8]

I was confused i understand now my bad

 

[ozzieAI]

those roots definitely have rotted...clean off best you can and remove most of the leaves leave on the young growing ones intact...seaweed both watered and sprayed will help a lot...they may look sick for a while and may never cover unfortunately..

good luck...

 

[bluefoodie]

I figured out what caused the root rot...it had to be the neem oil. It was the only thing I did differently. Before the watering with neem, the pots went from soaking to dry in 2 days. The plants were drinking about 330 mL of water per day (by weight). Two days after the neem oil watering, the pots were still heavy.

But others have done the neem oil soil drench without problems, what was different here? Then it hit me, and now I'm kicking myself for not thinking of it...the neem oil wasn't emulsified properly! I guess because it was 70% neem oil extract, I thought the 30% contained some emulsifier. And the directions didn't say to add any emulsifier, but that's only for spray applications. That was my fatal mistake. I mixed up some of the neem oil in proportion to water and sure enough, the neem soil soon formed a layer on top of the water.

I think what happened was as soon as the neem oil coated the roots, they suffocated, couldn't take up water, and then root rot set in. Water absorption went from 330 mL per day down to 210, then 125 mL per day immediately after the neem oil treatment. So, lesson learned, this is how not to drench my soil with neem oil!

 

[ozzieAI]

70% neem + 30% emulsifier = 100% (the usual mix) also neem does not cause rot. the smell you got when flushing was rotten smell as you described and neem can sit for days without causing that type of smell. neem also shouldn't leave a residue in the soil and i have never found any residue on the roots ever. i transplanted some plants today that got the neem treatment a few days ago and all i saw were a heap of white healthy roots...

when you mix it with water do you get any oil floating on the top or does it all disperse?

how much neem did you add and what brand are you using?

do you let the plants sit in the runoff for extended periods of time?

I mixed up some of the neem oil in proportion to water and sure enough, the neem soil soon formed a layer on top of the water.

does your soil usually sink if untreated with neem?

sorry for all the questions but i trying to work out what factors lead to your problem.

i have mixed up to 12ml/litre without any issues...neither have the other 3 growers i know that use it as well...

personally i think you had issues before the neem was added

were you able to save any of the plants?

 

[Crooked8]

^^this guy loves neem more than i even do. I absolutely love it also, but id never do a root drench with it. Oil on roots = bad. Not trying to argue but my personal opinion is that the roots could have rotted as a result of the neem use. Especially is it wasn't emulsified that much. Think about it, you're coating a root that needs oxygen and nutrients, if you coat it in anything, you're sealing out oxygen and food also possibly causing them to rot and die off. I dunno I'm no scientist, but i know plants.

 

[ozzieAI]

just to be clear this is the neem oil i use: http://www.batphone.com.au/products/wetting-agents-adjuvants/neem-plant-spray-1-litre.html

and this is the blurb: Neem Oil has been used as a fertiliser and wetter sticker for centuries. Our Neem Plant Spray is pure Neem Oil mixed with an organic emusifier enabling it to be mixed with water or fertilisers. It is an excellent adjuvant for fertiliser or as a stand alone product. Ideal as a floliar to make plants shine, as a soil drench for soil conditioning or as a fertiliser enhancer wetter sticker. The Japanese include our neem in their fertilisers via dripper at a rate of 2 mL per litre as ther have done for many many years. BFA Registered.

i also found this:

Please Note: Drenching potting soil with neem will adversely affect the beneficial biology of the rhizosphere. If you need to drench the root zone with neem, a follow up application with a good quality actively aerated compost tea will help to re-inoculate the beneficial bacteria, fungi and protozoa.

from here: http://urbangardenmagazine.com/2010/11/neem-oil/

i use beneficial bacteria in my grow along with the neem without issues, but do re-inoculate every month or so...

doing a simple google search will bring up plenty of hits re: neem oil soil drench

also consider that all of my plants (except the control plants in my side/side experiment) shown in my current album have had multiple doses of neem oil as a soil drench

if neem was your problem i would like to be able to track down what caused this negative reaction in your grow...

 

[bluefoodie]

when you mix it with water do you get any oil floating on the top or does it all disperse?

how much neem did you add and what brand are you using?

When mixed as directed (I used 1 Tbsp or 15 mL for 2 L of water), the water turns milky, but after settling a yellowish oily layer forms on top. This is the brand I used. It has 30% "inert ingredients" which may not include an emulsifier.

do you let the plants sit in the runoff for extended periods of time?

does your soil usually sink if untreated with neem?

No, I let the runoff drain out fully before putting the pots back. Not sure what you mean by sink, but I'm using Ocean Forest cut with 25% perlite, pretty standard mix.

The two plants are "stable" I guess. They still look like shit...old leaves have wilted, but there's some new growth (not much tho, especially on the second plant). They might just make it, but I don't wanna get my hopes up just yet.

Since this is my first grow, I only have these 2 right now. If they recover, I'm gonna grow some clones out to be mothers. Then I can take clones to test my theory (grow 3 clones, then water one regularly, one with neem oil but emulsified with Protekt and liquid soap, and one with neem oil mixed straight out of the bottle).

Also, here's a guy on another forum who supposedly had some problems with a neem oil drench.

 

[ozzieAI]

thanks for your responses BF.

yesterday i spent a few hours searching for more info about using neem as a soil drench. i too found that same thread you found, but his experiences differ from yours

After one week i am noticing leaf edges slowly but progressively going brown and crisp.They seem to have stopped growing.

this comment:

the water turns milky, but after settling a yellowish oily layer forms on top

could be what differs from your neem mix and mine...i never get settling even after days of my lazy arse leaving the unused mix sitting in my watering bucket.

looking at the brand you bought i cannot find what they mean by 30% inert ingredients???
they don't mention needing to add any emulsifier, but they also don't mention using it as a soil drench like the brand i use.

so maybe all neem oils aren't a like????

i really do appreciate you doing comparison exercise to see what works re: neem oil and what doesn't

most of the info i found pertained to neem cake soil amendments not oil unfortunately. neem is anti bacterial so may have killed off your micro herd that could have been the catalyst for the rot.

but this study showed that neem cake improved the soils..

The rhizosphere population of bacteria and fungi were increased in the amended soils compared to nonamended soils.

http://www.jbiopest.com/users/LW8/efiles/A.Sutha_2_3.pdf

again thanks for you input

i do wish you the very best in getting your plants to recover and the fact that you have some new growth is a positive sign

 

[PoopyTeaBags]

that deff root rot...

 

[bluefoodie]

Thanks ozzieAI, if my girls pull through it'll be because I took your advice before it was too late. I had no clue that root rot had taken over and wouldn't have thought of a bare root transplant to save the plants.

I agree that the formulation of the neem oil I used was the problem. The problem wasn't that it was neem, it was the fact that it was an oil and it wasn't emulsified. Here's some other advice I got:

oil on the roots is not a good thing. roots need to breathe.

sick plants will never die overnight
plants with no oxygen will die overnight

70% hydrophobic neem oil????.you used the OIL?? Not the gardening variety??

Dude i hope you added some surfactant in there. Neem oil needs to be dissolved into water before it can be used.
you get neem oil meant for gardening which already has surfactants to help it dissolve.

I think u used the "OIL" which coated your roots and prevented any further oxygen or nurtrient take up. Leading to overnight death.

The "oil" is also much more potent and concentrated than gardening varieties. You should not use it. If you do! lower the dosage significantly and add a lil bit of soap.

I found that there are basically 3 types of "neem oil" sold for gardening: pure 100% neem oil (e.g. Dyna-gro Pure Neem Oil), concentrated 70% hydrophobic extract of neem oil, and 0.9% "ready-to-use" sprays. I suspect that the "Neem Plant Spray" you use from Plant of Health is at a low concentration. Does it specify on the back of the bottle what the neem oil percentage is, and whether it has surfactants/emulsifiers already added to it?

 

[medicalmj]

Neem is great for many things. But I generally I don't use my neem for drenches, I use azamax (processed neem) for drenches.

Any time you use neem it should be added to warm (80-100F) water along with surfactant (i.e. coco-wet or non-ionic soap like dawn). If added to cold water and/or w no surfactant it can smother your roots. And the plant will wilt.

I don't like adding soap to my medium so I use neem for foliar and azamax for drenches.

 

[ozzieAI]

just wondering how you are going BF...how's the plants?

 

[bluefoodie]

just wondering how you are going BF...how's the plants?

They live! Looking better and better every day. I was too late to save most of the branches on the second plant, so it's mainly that one branch that's growing.

Just curious...did you find out the concentration of the neem product you use? Like when you mix 5 mL/L is it 5 mL of 100% neem oil?

 

[ozzieAI]

i am glad you have had some success...best to remove the dead limbs

sorry i missed your question BF...mine from memory is 70%, it is not as thick as the pure oil i have and way thicker then the ready to use stuff i have seen in the past...

good luck

 

[ozzieAI]

how are the plants doing BF?

 

[kiwi_growa]

BF i recently had an infestation of Winged Root Aphids. My neem tree oil settled at the top just like yours did. I shook the bottle up a lot and watered asap to avoid any settling and to get even dispersion of the oil. The plants lived and the Winged root aphids are minimal. I've only spotted 2 since doing the root drench and foliar feed 4 days ago. The neem oil had a huge affect. Didn't wipe them all out, but definitely put a dent in there progression. The plants are back to usual today and growing fast as ever. Neem oil is underrated.