"Alright," I said to Lightfoot on our John Muir Trail hike in 2012. "Smell this sock again and tell me if the baking soda made any difference." The sour look on his face gave me the answer as he slowly handed the sock back to me.
After a while on a long distance hike, you start to lose your ability to smell yourself, at least to a certain point. This is a blessing when you're alone, otherwise it's a curse. It would be great if I was a cartoon and could just look up to see if there were stink lines drawn above my head, but sadly I'm not, so Lightfoot offered to smell my socks after a thorough rinse and again after they had soaked in a baking soda and water solution for thirty minutes. Only a true friend would take a bullet like that.
"Hmm, alright, next time I'll let it soak longer or add more baking soda."
I began experimenting with environmentally-safe ways to clean my clothes in the backcountry after hiking the Appalachian Trail. Since I started backpacking, I've pretty much started to define "clean" as "dry," so don't get me wrong, clean out there isn't the same thing as clean at home. I decided, however, that long-distance backpacking would be more enjoyable if I could feel cleaner. Being tranquil and at peace in the natural world is a lot easier if you don’t smell like a corn chip’s foot. That's why cleanliness is next to godliness, and why you haven't seen a drawing of Buddha with stink lines above his head.
First, I pack a recycled plastic bread bag or a one-gallon Ziploc and at least 2 tablespoons of baking soda. Since I'm usually only washing one or two pairs of socks, a pair of underwear, and a lightweight shirt at one time, the bread bag or Ziploc is big enough.
1. After setting up camp at the end of the day, I put the offending clothes into a one-gallon Ziploc bag.
2. Then I add water.
Don't put the clothes directly in the water source. Clothes hold residual detergents from previous washes, which you may see proof of in the form of suds during the next step. Clothes may also contain other chemicals from deodorants, bug sprays, etc. Consider putting your backpacking clothes through another rinse cycle after you've washed them at home.
3. Seal the bag with a little bit of air inside. Now, shake it vigorously. This is where most of the cleaning happens, and the longer you agitate the clothes the cleaner they'll get.
4. Make sure you're at least 200 feet from all water sources then empty the bag and squeeze as much water out of the clothes as you can. Avoid twisting wool and synthetic fabrics when wringing out the water. It's less damaging to roll them up and squeeze the water out.
Repeat steps 2 through 4 as often as necessary. I usually do it 3 to 5 times, and agitate for at least a couple minutes each time.
This alone will make a tremendous difference, and more so the longer you agitate and the more times you replace the water as you do it. Your clothes will be a lot less smelly, and a lot more comfortable to wear. Actually, if your clothes weren't that dirty to begin with, water and agitation would probably be enough to get them clean. After wearing the same clothes on the trail for a couple days, however, they'll probably still smell at this point, but hey, at least people won’t be able to smell you from ten feet away.
If you want to stick with slightly smelly clothes to save weight in your pack and have as little impact on the environment as possible, feel free to skip the next two steps. If you want to get them cleaner, however, it's time to get out the baking soda.
5. If you want to remove a stain, mix a little water with baking soda to make a paste, apply it to the stain, gently rub the stained fabric into itself, and then continue.
6. Fill the bag with about a quart of water and about 2 tablespoons of baking soda (more on why I don't use detergents below). Shake vigorously to mix. If you need more water to cover your clothes, just increase the baking soda as well by roughly that same ratio. It doesn't have to be exact.
Now, let that soak overnight.
7. In the morning, go about 200 feet from all water sources, squeeze the baking soda water out the clothes, and then rinse them in the same way as steps 1 through 4.
8. I attach the wet clothes to my backpack using safety pins, so they can dry while I hike. If it's warm enough, I'll just wear the shirt wet. The synthetic or merino wool fabric my shirts are made of dry quickly from body heat. The odors will continue to decrease as your laundry dries in the sunlight.
Safety pins also work great to hang clothes on a line, so wind doesn't blow them off and so you don't have to fold them over the line, which makes them take longer to dry.
9. And finally, go find Lightfoot and have him sniff your sock to see if it worked.
Here are a few other tips for keeping your clothes clean in the backcountry:
1. You can reduce odor and the number of times you have to wash your clothes, if you wear clothes made of merino wool. It doesn't absorb body odors or hold onto bacteria like most synthetic fabrics, like those used in Under Armor for example.
2. Choose clothing made of materials that will dry fast in the sun. Hiking clothes made to quickly wick moisture from your body will likewise dry fast in the sun after you wash them.
3. If it's overcast and your socks are still a little damp at the end of the day, put them in your sleeping bag at night. Your body heat will help dry them out.
4. Before heading to the trail, wash your clothes at home with just water. This will remove residual detergents and make it safe to jump in a lake with your clothes on to give them a quick wash.