Cleaning out spray bottles


I have a couple of the one gallon pump sprayers.

Last Year, I used one of them for herbicides (mostly roundup), and one of them for pesticides. I can’t remember which one is which.

What is a good way to properly clean them so I don’t risk spraying herbicide on something I don’t want to?

I don’t know if running clean water through them a few times would work, I’ve also heard of various products that can be used to neutralize the chemicals.

And no, I am not looking to start a roundup debate here, I just want to know how to clean everything.


For $15 you can buy a new plastic sprayer of that size, if it was me I would just go buy another to use for insecticides and fungicides. Leave the old one with Roundup use dedicated to Roundup use. Put a permanent tag on the hoses.


Mark one roundup this time. I think a good detergent should work, and spray for a few minutes too. Vinegar makes windows streak free, bet a 25% vinegar solution or more would clean it extremely well.Probably will remove residue from the screen and wand too making flow as best possible. Works good on coffee pots too.


I use Simple Green to wash them out. It’s a good solvent and supposedly biodegradable.


I agree with Turkey Creek- for 15 bucks why risk it?

But if you care to try I’d suggest a thorough soak with dilute household bleach followed by a good wash and then a test run on tomatoes or beans.

My idea is that you want to oxidize any remaining herbicide, and it has to be soaked out of the plastic, which might take some time. If it were just glass or stainless a thorough wash would do the trick.

Or I might just be full of it. Spend the $15.00!



If you bought another sprayer you would have three,. Roundup breaks down so quickly you probably don’t even have to wash it. 2-4d is the one that just tends to stick around.
I would wash it as it is protected in the sprayer, still I don’t think this is a big deal.
Most of the weeds around my house laugh at roundup, at least in the weak solutions they sell in ready to use formulations.
When you see deformed leaves and such that is almost always 2-4d.
I never buy the brand name product it is so weakly formulated. Other companies make it much stronger. Patent is expired.

Bleach is a hell of a lot more deadly than roundup, yet people use it all the time to clean stuff. I myself would never put bleach in my sprayer. It even destroys metals. My sprayer has a metal wand and nozzle.


You’re right Drew, in that bleach is very corrosive, but it’s also very fugitive and can be easily washed out, which is something I don’t think is true about glyphosate. And yes, 2-4d type products are more persistent, but keep in mind that glyphosate doesn’t actually break down quickly until it contacts organic matter- so in the plastic of the sprayer it might retain some strength. At least, that’s my thinking, for what it’s worth!


I am curious as to what farmers use there… Presumably if you grew corn and soy you’d be in a position where you might want to spray corn with one of the synthetic auxins that have no effect on corn, and turn around a spray Roundup or a fungicide or insecticide on RR beans the next day with the same sprayer.


Yeah you’re probably right, I heard of problems, I feel though buying a new sprayer is overkill. I guess it’s one own experience. I finally found a good sprayer, i have gone through 4 of them, and 3 lasted a week. One lasted 5 yeas. Of course it was bought from a 3rd party vendor (English Gardens). They don’t have anymore, and no manufacturer marks are on it. Most sprayers suck, when you find a good one protect it with your life! I myself would never buys a 15 dollar sprayer, that tells me it will leak in a weak or the pump would break…

I still would not use bleach as I would probably get some on my shirt, or pants. Plus just a little left in could ruin my sacred sprayer. I would use soap and water, then vinegar and it should be clean as a whistle! (Why are whistles so clean? Seems like they would be disgustingly dirty! )


My wife does sigh at times when she sees what I’ve done to my clothes …


LOL! Yeah me too, really bad these days! Yes, bleach here may be called for to make sure that crap is out of there! I try not to use roundup, but once in awhile I do use it. hardly ever though once a year at the most, if that. I use cardboard in my raised beds. In the fall once everything is out of the beds I cover with cardboard and them cover with compost


Agree with this simple green should work great for that purpose.