All Natural Spider Mite or Powdery Mildew prevention and cure.

February 14, 2014 5 Comments

Kill and Prevent Spider Mites & Mildew with a DIY Neem oil spray

This do it yourself pest spray will fit perfectly into your current gardening program and is a favorite recipe that has kept me PM free for years. This will knock out spider mites and is safe and non toxic.

List of items that I use in this tutorial:

1. Neem Oil - I like the stuff at but I am using DynaGro Neem Oil in this video because that's most likely what you will have locally. 

2. Agsil16H Potassium Silicate-  In this tutorial I use a Pre-Mixed version of this with 140 Grams Agsil16H to 32 ounces of water. 

3. 200x Aloe Vera Powder - You can use fresh or get this powder, either way it's excellent.

4. Dr. Bronners Lavender Soap - If you have peppermint, use that, but I've using lavender lately.

5. Protein Shaker Cup or a Glass Jar with Lid. You could even just use a glass and a whisk.

6. Sprayer you'll be using to apply this with - I prefer the Chapin model 1949. Seriously it's awesome. 


Recipe Per Gallon of warm clean water:

1oz Neem or Karanja Oil

1 Tablespoon Agsil16h solution or use Dyna Gro Pro-tekt

1oz Dr. Bronners soap. (Mix it up: Use unscented and add your own essential oils at 5-7 drops or use lavender like this recipe calls for)

1/8 Teaspoon of our Organic 200x Aloe Vera Powder

If there is a current infestation going on, you can up your dose to 2 oz Dr. Bronners and up to two ounces of Neem.... start with 1.5.


Directions for Making the spray:


Step 1: Get some WARM water into your sprayer and use the best water you can. (Don't use hot water)

The 10 Stage Water Filter is the easiest one I could find to move around and fill up buckets and sprayers with.

It is about $85.00 on Amazon and will last for 1 year. (1500 Gallons or so by my calculations)

If you put 4 gallons into a bucket everyday, this filter will last over 1 year easy.

(I don't have any relationship with this company but like the product)



 Step 2: Get the Neem Oil Warm and easy to pour. I use how water from the tap in bowl.

You can see this in the photo below on the left. (Just soak the bottle in warm/hot water for a few minutes and then shake it like crazy and soak for a few more minutes. If you haven't opened the bottle yet, break the seal before you shake it, this will make it easier to move around in the bottle.




Step 3: Get Your Aloe Mixed First and let it sit inside the sprayer with just plain water.

I am mixing up enough for two gallons so I'm using just under 1/4 Teaspoon of our Pure 200X Aloe Powder.


I like to add this to a Blender Bottle Shaker cup thing and shake like Crazy!



After the Aloe Sits for a 10 minutes of so it will turn clear again. Then I pour it into my Chapin Sprayer to hang out while I make the rest of the spray in the Shaker Cup.


Step 4: Emulsify Neem by Combining Neem and Agsil16H Solution.


Use 1 ounce of Neem Oil Per gallon for prevention and up to 2 ounces per gallon if you have an infestation. 

Neem oil is Phytotropic and is best sprayed at lights out. 


I first add 2 ounces of neem because I'm making 2 gallons of spray. I add this to WARM water, NOT hot water or cold water.

Here is the Neem and the the Shaker Bottle with Neem and Water in it.


Next I'm going to add 2 Tablespoons of Agsil16H Concentrate Which I make in advance and keep on the shelf. 

(I Mix 140 Grams of Agsil16H into 32 ounces of water and keep the bottle around for this situation)

Then Shaken Like Crazy for a minute or two:


Step # 5: Adding the Neem Solution and Soap to your Sprayer.

Use Dr. Bronners Soaps at 1 oz per gallon for prevention and up to 2 oz per gallon for infestation.

I'm making 2 gallons of spray at 1 oz of soap each. I'll dump this straight into my sprayer before I add the Neem Solution that was just made.

After adding the soap to the sprayer it's time to pour your Neem solution in:


Step 6: Put your sprayer back together and SHAKE like crazy!

If you have a Chapin don't shake it over your toes, I've had it smash my toe before and almost broke it. 

Hold the handle and the side and shake it in between your legs.


Step 7: Spray your plants!

Now that your sprayer is full of pest and mildew crushing awesomeness, you are ready to spray.

Do this right before lights out or at dusk and spray the bottom of the leaves first starting at the bottom and working your way to the top and then spray from the top down and get the plant completely soaked until it looks like it's weeping and about to fall over. 

Make sure there is good airflow and come back and check in the morning. 

If you have no infestation and are doing this for prevention, I would perform once every week or 10 days. 

If you see any signs  of problem than perform every 3 days to kill the eggs and the adults before they can reproduce again.


If you have any comments please post them!!

5 Responses


October 26, 2020

great info as usual. do you think this could be effective to prevent / control leaf spot ?? we have a garden deep in the woods that always gets leaf spot every year. the trees all seem to get it in the surrounding areas


October 26, 2020

Hello Roger! Thanks for the comment.

“Hey Guys, I got two questions for ya. 1) Is your natural spider mite and mildew treatment effective for fungus gnats? 2) What exactly is Agsil16H? Is that just the brand name of a product? I am just wondering if I can get the same or similar product here in Sydney, Australia.”

1. Fungus gnats are different and typically don’t host themselves on the leaves but on the surface of the soil. If you happen to have a source of quality vermicompost or worm castings I would topdress a 1-2 inch layer solid across the top of your soil container and the fungus gnats will be gone almost immediately. If that isn’t an option, then you can get some Mosquito dunks. The mosquito dunks use a harmless bacteria that will kill the larvae of the fungus gnat and then you will be good to go again. Here is a link on amazon for a reference of what I’m talking about
They are typically used to float on open ponds to keep mosquito’s from developing. You can break off half of a dunk and sprinkle it around your soil container and that will do the trick.

2. Agsil16H is a particular formulation of Potassium Silicate. Potassium Silicate is a mineral and the ratios of potassium to silica are labeled by the company that produces them. Agsil16H is speculated to be the “secret” ingredient in most of the Silica products on the market like Silica Blast, Rhino Skin and Pro-Tekt. You should be able to get Dyna-Gro Pro-Tekt for a good price locally. If not I can also ship you Agsil16H to australia and work out a special price to help cover the extreme shipping costs. I would only want to do that if you can’t find something more affordable locally. Just let me know!


October 26, 2020

Hey Guys, I got two questions for ya. 1) Is your natural spider mite and mildew treatment effective for fungus gnats? 2) What exactly is Agsil16H? Is that just the brand name of a product? I am just wondering if I can get the same or similar product here in Sydney, Australia.

Thanks for you help,



October 26, 2020

Great Question Mark!

“Could a gallon be made up and sit in a cool dry place and used as needed, or should it be made and used in same day?”

I wouldn’t do this because the aloe can go bad without preservative and the Neem will go out of suspension in the water and become all oily again and clumpy.

All the sources I have say to use this spray right away! I sometimes use it in the morning and then shake it like crazy and again at night on some other plants…. so It’s go with what works best for you.

Another reason to make this fresh it that you can change the recipe so that bugs don’t get used to it.

You can change from lavendar soap to peppermint or something like that… heck you could even add plain soap and add your own essential oils at about 5-7 drops per gallon.

Sometimes I do just neem and agsil16h, sometimes I do just soap! So if you are short on time just go with straight soap at 1-2 ounces per gallon and spray like crazy!

It all works, but the recipe here is this post used just after mixing is very effective.


October 26, 2020

Could a gallon be made up and sit in a cool dry place and used as needed, or should it be made and used in same day?

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