Making your own infusion is basically a rite of passage. If you've ever tried to hover over a stove for four hours, watching a thermometer like a hawk so you don't burn your stash, you know it's a nightmare. It’s stressful. One spike in heat and you’ve toasted the terpenes and turned your expensive flower into sleepy, CBN-heavy sludge. That’s exactly why weed butter in a crock pot is the goat. It’s the "set it and forget it" method that actually works, provided you don't skip the most important step: decarboxylation.
You can't just throw raw bud into melted butter and expect magic. Science doesn't work like that. Raw cannabis contains THCA, which isn't psychoactive. You need heat to break off that carboxyl group and turn it into THC. While some people claim the slow cooker gets hot enough to decarb while it infuses, they’re usually wrong. Or at least, they’re getting a much weaker product.
The Decarb Dilemma and Why Your Crock Pot Needs Help
Before we even touch the slow cooker, we have to talk about the oven. Most experts, including the folks over at Leafly and High Times, agree that 240°F (115°C) for about 30 to 45 minutes is the sweet spot for decarbing. You’re looking for a light toasted brown color. Not black. Not green. Think toasted coconut.
Once that’s done, the crock pot takes over the heavy lifting. The beauty of weed butter in a crock pot is the temperature stability. Stovetops have hot spots. Slow cookers circulate heat in a way that keeps the lipids (the fats in the butter) and the cannabinoids shaking hands for hours without scorching.
Honestly, the smell is the only real downside. Your whole house will smell like a dispensary. If you’re trying to be stealthy, this isn't the move. But if you want potency? This is it.
Setting Up Your Infusion Station
Don't use cheap butter. Seriously. Cannabinoids are fat-soluble. This means they need fat molecules to bind to. High-fat European style butter or clarified butter (ghee) is significantly better because it has less water content. If you use standard salted butter, you’re going to get a lot of watery "milk solids" at the bottom of your jar that can cause your butter to mold faster.
Here is what you actually need:
- At least a half-ounce of decarbed flower (or trim, but adjust your expectations).
- 1 lb of unsalted butter (4 sticks).
- 1 cup of water (this is the secret to not burning the butter).
- A slow cooker with a "Low" or "Warm" setting.
- Cheesecloth. Do not use a coffee filter; it’ll tear and leave you frustrated and covered in oil.
Why the water? It’s a safety net. Water boils at 212°F. As long as there is water in the pot, your butter won't climb much higher than that, which prevents the THC from degrading. Plus, it helps wash away the chlorophyll, which is why some cannabutter tastes like a literal lawnmower bag. The water absorbs that "green" flavor, and since oil and water don't mix, you just separate them later. Easy.
The Long Game: Time vs. Potency
There’s a lot of debate about how long to let it ride. Some people say 4 hours. Some say 24. Honestly, after about 6 to 8 hours, you’ve reached the point of diminishing returns. You aren't getting "more high" at hour 12; you’re just extracting more chlorophyll and plant waxes, making the butter taste worse.
Set your crock pot to "Low." If your "Low" setting feels particularly aggressive, use "Warm." You want to see tiny bubbles, but not a rolling boil. If you have a digital thermometer, aim for a consistent 160°F to 180°F.
The Messy Part: Straining and Separating
After your house smells like a 1970s rock concert and the timer goes off, let it cool for a bit. Not so much that it solidifies, obviously, but enough so you don't get third-degree burns. Drape your cheesecloth over a glass bowl. Use a rubber band to hold it tight.
Pro tip: Don't squeeze the cheesecloth too hard.
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I know, it’s tempting. You want every last drop of that liquid gold. But when you squeeze the living daylights out of the plant material, you’re forcing more bitter chlorophyll and plant matter into your final product. Give it a gentle press and let it be.
Put the bowl in the fridge. Over the next few hours, the butter will rise to the top and solidify into a hard puck. The nasty, brown, swamp-looking water will stay at the bottom. Pop the puck out, dump the water, and pat the bottom of your butter dry with a paper towel. Excess moisture leads to mold, and nobody wants fuzzy butter.
Dosage is Where People Mess Up
This is where things get real. Homemade weed butter in a crock pot is notoriously hard to dose. You aren't a lab. You don't know the exact percentage of THC in your flower.
If you used 14 grams of flower with 20% THC, you theoretically have 2,800mg of THC. But you lose some during decarb. You lose some during infusion. You lose some in the cheesecloth. A safe estimate is usually around 60% efficiency for home cooks.
Do the math.
If you end up with 2,000mg in 4 sticks of butter, that’s 500mg per stick.
A tablespoon is 1/8th of a stick.
That’s roughly 62mg per tablespoon.
For many people, 62mg is a "see you tomorrow" kind of dose. For others, it’s a Tuesday. Always test your batch by eating a small amount—like a half-teaspoon—on a cracker and waiting two full hours before deciding you "don't feel anything." That’s the classic mistake that leads to people melting into their couches and questioning their life choices.
Storage and Longevity
Cannabutter doesn't last forever. Because you’ve introduced moisture and handled it, it has a shorter shelf life than regular butter. It’ll stay good in an airtight container in the fridge for about two weeks.
If you aren't going to use it all at once, freeze it. I like to use silicone ice cube trays. Each cube is a pre-measured dose. Once they're frozen, toss them into a freezer bag. They’ll stay potent for six months or more. Just don't forget to label the bag. Finding "mystery butter" when you're just trying to make toast on a workday is a recipe for a very weird morning.
Common Mistakes to Avoid
- Grinding too fine. Don't turn your weed into powder. It makes it impossible to strain and your butter will be gritty. A coarse hand-grind or just breaking it apart with your fingers is plenty.
- Skipping the water. I've seen so many people burn their batch because the crock pot ran too hot and they didn't have a water buffer. Use the water.
- Patience. You cannot rush the cooling process. If you try to separate the butter before it’s fully hardened, you’ll lose half of it in the water.
- Cheap equipment. If your crock pot is from 1984, the heating element might be unpredictable. Test it with just water first to see if it maintains a steady temp.
Infusing at home gives you a level of control you just don't get with store-bought edibles. You pick the strain. You pick the butter quality. You control the potency. Once you master the crock pot method, you’ll realize why it’s the gold standard for home enthusiasts.
Your Next Steps
- Source high-quality fat: Go buy some grass-fed, unsalted butter or jarred ghee.
- Temperature check: Use an oven thermometer to ensure your decarb is actually happening at 240°F, as most ovens are off by 10-15 degrees.
- Clean your gear: Make sure your slow cooker is spotless to avoid any "off" flavors from last Sunday’s pot roast.
- Small batch testing: If this is your first time, try a half-batch (2 sticks of butter, 7 grams of flower) to get a feel for your specific slow cooker's heat levels.