Learning how to clean sheep fleece is mostly about managing heat and avoiding the urge to scrub everything like you're doing the dishes. If you've just acquired a raw fleece—maybe straight from a farmer or a friend with sheep—it can look pretty intimidating. It's usually full of dirt, bits of hay, and a sticky, waxy substance called lanolin. But honestly, once you get the hang of the temperature and the timing, it's a really satisfying process that turns a dirty mess into something beautiful and soft.
The big secret is that you aren't actually "washing" it in the traditional sense. You're more like "steeping" it. If you move the wool around too much while it's wet and hot, you'll end up with a solid brick of felt, and there's no coming back from that.
Getting Started with Skirting
Before any water touches the wool, you have to do the dirty work. This is called skirting. I usually do this outside on a mesh table or a big piece of cardboard. Spread the fleece out flat and take a good look at it.
You're looking for "VM"—that's just fancy talk for vegetable matter like straw, burrs, and seeds. You also want to pull away the "tags," which are the clumps of wool heavily coated in manure or mud, usually from the back end of the sheep. Don't try to save these; it's just not worth the effort.
Shake the fleece out a bit. You'll see a lot of dust and loose dirt fall through. The goal here is to get rid of anything that doesn't belong so you aren't washing literal trash. It's a bit dusty and can be a little smelly, but it saves you so much time during the actual washing phase. If you skip this, your bathwater will turn into mud instantly.
What You'll Need
You don't need a specialized lab to do this. Most of what you need is probably already in your house, though you might want to buy a dedicated tub if you plan on doing this often.
- Mesh laundry bags: These are life-savers. They keep the wool together so it doesn't float all over the place.
- Heavy-duty dish soap: Something like Dawn is a classic because it's a grease-cutter. You need something that can break down the lanolin.
- A large tub or sink: A plastic utility tub works great.
- Hot water: And I mean hot. More on that in a second.
- Rubber gloves: To protect your hands from the heat and the grease.
The First Soak: Breaking Down the Grease
The first real step in how to clean sheep fleece is the "scour." This is the part where you remove the lanolin. Lanolin is a natural wax produced by the sheep, and it's what makes the wool feel sticky or tacky. To get it off, the water needs to be hot enough to melt it—usually around 140°F (60°C). If the water is just lukewarm, the grease will just move around and then settle back onto the fibers as the water cools.
Fill your tub with hot water first, then add your soap. Don't pour the water directly onto the wool, as the force of the stream can cause felting. Once the tub is full and sudsy, gently push your mesh bags of wool down into the water.
Don't overstuff the bags. The wool needs room for the water to circulate. Once it's in, do not agitate it. Just let it sit there. I usually leave it for about 20 to 30 minutes. If you leave it too long and the water cools down, that melted lanolin will solidify right back onto the wool, making it even harder to clean.
The Second Wash
After 20 minutes, lift the bags out gently. Don't wring them! Just let the water drain out naturally. You'll probably be shocked at how brown and gross the water looks. That's a good sign—it means it's working.
Refill the tub with more hot water and soap, and repeat the process. Depending on how "greasy" the sheep breed is (Merino is way greasier than something like a Romney), you might need to do two or even three soapy soaks. You'll know you're getting close when the water starts looking less like swamp water and more like slightly dirty dishwater.
The Rinse Cycles
Once you're happy with the cleanliness, it's time to rinse. The most important rule here is to keep the water temperature consistent. If you take wool out of hot soapy water and dump it into cold rinse water, you'll "shock" the fibers, and they'll felt instantly.
Fill the tub with clean hot water (no soap this time) and let the wool soak for another 15-20 minutes. You might need to do this twice to make sure all the bubbles are gone. If you still feel a sticky residue on the wool, it means you either didn't use enough soap or your water wasn't hot enough to move the lanolin.
How to Dry the Fleece Properly
Now that it's clean, you have a heavy, dripping wet pile of wool. To speed up the drying, you can put the mesh bags into your washing machine and run the spin cycle only. Do not let the machine spray water on the wool, and definitely don't let it agitate. You just want the centrifugal force to pull the excess water out.
After the spin, the wool will be damp rather than soaking. Spread it out on a drying rack or a clean screen. Don't hang it up, or the weight of the water will stretch the fibers.
It's best to dry it in a spot with good airflow but out of direct sunlight. Direct sun can actually make the wool a bit brittle if it sits there too long. Depending on the humidity and how thick the wool is, it might take a day or two to dry completely. Don't rush it by using a blow dryer or putting it near a heater—just let it do its thing.
A Few Tips for Success
One thing people often worry about is the smell. Raw wool has a very distinct "sheepy" scent. While the washing gets rid of the dirt and most of the grease, a faint smell often remains until the wool is completely dry. Don't panic; it usually fades away.
If you're working with a very fine wool, you have to be even more careful. Fine wools felt much faster than coarse wools. If it's your first time figuring out how to clean sheep fleece, you might want to start with a "longwool" breed like Lincoln or Teeswater. Their fibers are sturdier and a bit more forgiving if you accidentally move the water too much.
Another thing to watch out for is "tips." Sometimes the ends of the wool (the parts that were on the outside of the sheep) are weathered or sun-damaged. These can stay a bit crunchy or yellow even after washing. That's normal. You can often flick those ends open with a comb later on during the prepping stage.
Why Do It Yourself?
You might be thinking this sounds like a lot of work when you could just buy pre-washed wool. And yeah, it is work. But there's something really cool about taking a raw product and seeing the transformation. Plus, when you clean it yourself, you get to decide exactly how much lanolin to leave in. Some spinners like to leave a little bit of "grease" in the wool because it makes it easier to spin and keeps the yarn water-resistant.
Cleaning it yourself is also much cheaper. You can often get raw fleeces for a fraction of the price of processed roving. It gives you a much deeper connection to the craft, and honestly, there's a certain peace in the slow process of skirting, soaking, and drying.
Once the fleece is dry, it'll be light, bouncy, and ready for carding or combing. You've successfully navigated the trickiest part of wool processing. It might take a few tries to get the water temp and soap ratio perfect, but once you do, you'll never look at a dirty sheep the same way again.