[ozzieAI]

This experiment/comparison is to see if neem works as a soil conditioner. there is much written about neem being used for pest control both as a foliar spray and too a lesser extent as a soil drench but little seems to be known about neem being used as a soil conditioner. in my threads about using neem as a soil drench several contributors stated that they thought apply neem to the soil was a bad idea.

to clarify i use neem that has been specifically made for agricultural purposes through the addition of an organic emulsifier. i apply two types of doses to my plants: 5ml/litre as a maintenance dose and 12ml/litre to fight bugs specially Root Aphids and fungus gnats. since using neem as a soil drench i have observed the following: excellent growth rates, healthy strong plants and a massive reduction in pests both indoors and out. what i can't quantify if neem helps the plant grow better than plants without neem.

2 weeks ago i took cuttings (14) from current vegging plants and out of those i selected 8 of the resulting clones based on root development consistency. all plants were planted in the same size pots with the same soil and the same amount of organic soil amendment was mixed into each pot. the 2 i selected to be excluded from receiving neem were the most 'middle of the road' plants out of the final 8.

i mixed a mild seaweed/fish emulsion mix and applied this to the 2 marked plants before adding 5ml/litre of neem oil and watering that into the rest of the clones (and vegging plants). i also applied a foliar spray of a mild mix of seaweed/fish emulsion/silica/potash to all plants. i will try and update this thread regularly for the next 4 weeks with comparison pics.



plants marked with the tags are the neem free. i will move all plants around once a week to ensure equal exposure to the light.



full grow room...

just a quick update:
here is a pic of 3 current seedlings at day 33. these plants have been watered with neem oil at 5ml/litre twice: once on day 14 and again 2 days ago...just to respond to some of the questions/statements posted. YES you can water emulsified neem oil into your soil and it WON'T damage your roots...but rather help keep them nice healthy...

as you can see nice healthy plants and roots....

[ozzieAI]

sorry guys i didn't see that my thread got posted after mod approval...

well the experiment is well and truly over with the result being that neem does help to develop more roots than plants that weren't treated with neem. however the actual plants themselves above the root line looked identical.

here are the shots for the first 4 weeks:





as you can see there is no difference in the plant development and if i didn't have the tags in i would not have been able to tell the which was which.

it was only when i repotted the plants that i noticed the difference in the rootballs. now i must apologise for i lost the pics showing the difference in the root development which i estimate to be 15 - 20% more roots for the neem treated plants.

i find it strange that a bigger root mass didn't equal bigger plants. all plants were very healthy and pest free...which is nice after fighting Root Aphids for so long. out of the plants shown, 3 were gifted to friends and the 3 i kept have gone outside and i still can't tell the difference between the neem treated and untreated plants.

i will keep using neem oil as a part of my watering program but i am dialing it back since i have been able to source neem cake to amend my soil. using neem for me has been more about fighting pests than conditioning the soil but i had to see if it was a benefit or not.

[canna woop!]

Nice test, way to put. The info out there

Canna woop!

I also spray budding plants with néem oil at 2 teaspoons per liter and as longas it's at night they grow on as healthy as ever.

I wouldn't use much else on budding plants, botanicals and botanical oils are the way to go

[VerdantGreen]

nice test. i use neem seed meal in my soul mix and that certainly helps with fungus gnats.

[moses wellfleet]

Would be better if you can do a side by side until the end of flower?

[Treetroit City]

I would think neem cake would be the way to go here. Just recently saw it on sale for three dollars a pound, seemed like a good deal.

[ozzieAI]

Would be better if you can do a side by side until the end of flower?

yes it would have been, but outside (where i flower) i have to give neem oil to protect the plants from the caterpillars and grasshoppers...

[moses wellfleet]

Oh yes thanx for your earlier reply by the way, I am using it indoors to combat spider mites and leaf hoppers do you think it will work against these pests?

[ozzieAI]

Oh yes thanx for your earlier reply by the way, I am using it indoors to combat spider mites and leaf hoppers do you think it will work against these pests?

i have beaten spider mites with using neem systemically but it does take it bit longer and bit of a higher dosage, leaf hopers should vanish pretty quickly once you introduce neem into your watering regime. if you have an issue with spider mites taking longer to be affected by the neem then spray a little on them directly to give them their marching orders. any insect that eats the plant will/should be affected by the neem. i have almost totally stopped caterpillars and grasshoppers (these at the worst give me minor damage if i miss a watering or two) in their tracks outdoors and FG, RA and spider mites indoors...

[VerdantGreen]

ozzie, do you have any info that proves categorically that neem is systemic? ive never been able to find any, and whilst the neem seed meal protects against soil borne pests it doesnt stop me getting mites.

VG