How Long to Mix Cannabis and Ice Water for Washing Bubble Hash

Todde Philips   

🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur

Washing hash involves mixing ice water and cannabis material together in order to separate trichome heads and isolate them through a series of mesh filter bags, called Wash Bags. The same material can be washed multiple times, and for varying lengths of time with each round of washing. The length of washing time impacts the number of trichomes released from the material, as well as the amount of plant contaminant that may end up in your hash. 

Washing for the right amount of time means releasing the ripe and mature trichomes without pulverizing the material and creating excessive contamination in the water. To get the maximum bubble hash yield with the least amount of contamination, it’s important to know the right length of time to agitate ice water and cannabis. 

What If You Mix Too Long? 

The biggest downside to mixing too long is getting excessive contamination in your hash. This can be true with either hand washing or machine washing. Overly-worked material will break down and release tiny plant particulates into the water, which often join the trichome heads on top of each mesh filter screen. These plant particles can sometimes be rinsed through the filters using a sprayer, but more times than not they will remain in part with the final product. 

Ice nucleation can also play a part in contamination if using fresh frozen material. If the mixing time is prolonged to the extent that the water begins to warm, fresh frozen material will begin to thaw and the chlorophyll trapped inside the plant will be released. Chlorophyll in this form is a challenge to remove from the hash, and you’ll likely be stuck with a green hue in your product. 




Although longer mixing times will generally increase the amount of hash you’ll pull from each wash, it can come at the expense of contamination. It’s better to run multiple, shorter washes of the material than just one or two longer washes, to help minimize the plant contamination. It also means you’ll yield a specific representation of trichome ripeness in each shorter wash, rather than including trichomes of various degrees of ripeness all in one run. This segmentation of trichomes lends itself to gathering a different grade of hash with every wash, a benefit when trying to isolate the very best resin. 

What If You Don’t Mix Long Enough?


Not mixing long enough carries with it less severe downsides than mixing too long. The main issue with not mixing ice water and cannabis long enough is leaving too many trichomes attached to the plant material. If the washes are too short the cannabis won’t release the maximum amount of resin glands into the water where they can be filtered and collected. This translates into a diminished yield. 



In terms of optimizing for quality, it’s better to be conservative with mixing time. 

What Is the Best Length of Time for Each Wash?

There’s no single best length of time to wash cannabis for bubble hash. One batch of cannabis material should be washed multiple times, as opposed to just one prolonged wash. Each time it’s washed, the length of time should be slightly increased. The first round is washed just briefly, then subsequent washes can be increased by several minutes. This means that with each wash, you’ll capture trichomes in different degrees of ripeness.  

The most ripe trichomes will separate from the cannabis material with just a brief mixing. Trichomes that are less ripe require longer washes to be separated from the material. So the initial short wash (after the brief rinse) targets the most ripe and fully mature trichomes, and as the length of washes increases, the less-mature trichomes will make up an increasing majority of resin to be collected. 

The aim is to mix just long enough to release mature trichomes without also releasing plant contaminants into the water. If the resin that collects on the mesh filters has a greenish hue, that’s a sign of contamination. Too much time mixing can play a role in that contamination. 

Also keep in mind that if you're washing by hand as opposed to washing with a machine (on delicate setting) then there will be some variation in the target times. 

Let’s look at an example wash and recommended timing. Let’s say you’re washing 8 ounces of air cured cannabis flowers. After a pre soak of around 30-60 mins to ensure the material is completely supple, the first wash will be very short at just 2-3 minutes. This will release only the most ripe trichomes. 

But first, before the actual wash, do a rinse off to remove dust, dirt, and any outdoor particulates that might be stuck to the flowers. This pre wash can be about 10 seconds, and all the water can be drained out as waste. You'll lose trichomes, but you'll gain cleanliness. 


The next wash can be a bit longer, in the range of 1.5-3 minutes. Then the third wash can increase more, to around 4.5 minutes. With each subsequent wash, increase the amount of mixing time. 


For the fourth wash and beyond, aim for around 6 minutes. Also keep in mind that with mixing times much beyond that, a greater likelihood for green contamination in your hash will be a factor. 

To summarize:

1st wash (rinse): 10 seconds then dump the water
2nd wash: 1.5-3 minutes
3rd wash: 4.5 minutes
4th wash and beyond: 6 minutes

In addition to the amount of time that cannabis is mixed during each round of washing, how many times you wash the material and the force used in mixing ice water and cannabis together both factor into the yield and purity of the final product. Find out more about the number of washes you can give to each batch of material in our article How Many Times To Wash Cannabis for Bubble Hash


These mixing times are guidelines, not rules. It's key to experiment and find out what works best with your setup and the strains you're running. These times are good guides for both machine and hand mixing. Hand washing is often less abusive on the material than machine washing, so the times can sometimes be a bit more with hand washing. 

Many factors impact the quality and yield of bubble hash washes, including length of mixing time. In the pursuit of the highest quality of hash, it’s better to err on the side of shorter washing times. And if you’re concerned that there are still trichomes remaining on the material, you can continue with subsequent rounds of washing. As long as the material continues to dump resin glands without excess contamination along with it, just keep washing. 

Also remember to presoak the material in the ice water for 30-60 minutes before beginning the first wash. This is a critical step to ensure the material is soft and supple and less likely to break down in the wash. If the material is mixed while it’s still brittle, expect more contamination in the hash. 

 For more reading on ice water extraction, check out our article on Top 20 Best Tips for Washing Hash.

What’s your ideal length of wash time? Let us know in the comments!





What if I wash cannabis for too long?
Extended washing times can lead to excessive contamination in your hash. It's better to err on the side of shorter washing times, and multiple rounds of washing. 

How do you mix cannabis and ice water?
You can use either a hand-stirring method with a spoon or paddle, or a washing machine to automatically mix the ice water and cannabis. 

How long should I mix cannabis and ice water?
Start with a short, 2-3 minute mix and then extend mixing time with subsequent washes. There’s no single best length of time to wash cannabis for bubble hash. One batch of cannabis material should be washed multiple times, as opposed to just one prolonged wash. Each time it’s washed, the length of time should be slightly increased. 

What if I don't mix cannabis and ice water long enough?
If your mixing time is too short, you can simply add more rounds of mixing. Otherwise you will risk leaving too many trichomes behind on the material. 

What is the longest time you can mix ice water and cannabis?
20-25 minutes is at the longer end of the mixing spectrum. Any longer than that and the risk for contamination is high. 


1 comment


Do I have to let the water sit for 10 minutes after I’ve stirred it? I’m using the pure pressure 30gal system

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