Several times over the past years, I have wished with all my heart I could call Mr. Migaki, my favorite teacher of all time who sparked curiosity and the love of science in my fifth-grade self. I needed to ask him about minerals and crystals and why something called borax can be powdery soft one day and hard as a rock the next.
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Dear Mary: Your Everyday Cheapskate column is one of the few emails I receive that I open and read every day, without fail. Both your product recommendations and your recipes are wonderful.
I also use your homemade laundry detergent recipe, and it works well to clean our clothes, but I have a question about it. The last batch I made went into two clean gallon containers, and as I was pouring the last out of the first container, I got a lot of white crystallized lumps at the bottom. So I strained the contents of the second container into another jug and got a lot of the same white crystalized lumps from it. So:
1. Did I do something wrong? The previous several batches were fine and lump-free, and I followed the same recipe with the same ingredients. (I know you probably can’t answer this, but maybe other readers have reported the same phenomenon?)
2. Do you know what these lumps are?
3. Is the strained liquid going to be an effective cleaning agent? Where I live in Southern California we’re still under drought water-usage rules. I don’t want to waste a couple washer loads of water with useless detergent if I don’t have to. Your thoughts would be greatly appreciated! Pat
Dear Pat: Let’s talk about this clumping, or as you call it “crystallized lumps.” This happens for me and I’ve heard from lots of readers who experienced the same thing. I notice this happening not right away, but maybe a couple of weeks after I make up a new batch of detergent.
I’ve been conducting my own research on this and am satisfied (not alarmed) by what I have learned. These crystals are completely harmless, if only slightly annoying. I shake the container in an attempt to break them up, but even if some remain at the end, I use them as if they were still liquified.
One of the properties of borax, which is a naturally occurring mineral mined from underground, is that it clumps easily when exposed to humidity. The clumping or hardening action is hastened with heat.
Our recipe for how to make laundry detergent instructs you to mix the borax and washing soda with hot tap water to dissolve them before proceeding with the other ingredients. That’s the way I have always done it but have been experimenting with changing that to regular cold tap water. While this has not stopped the crystallization completely, I believe I see less of it—and significant enough that I have amended the recipe to mix with cold water and shake well.
With that said, keep in mind that I live in a very dry climate, with very little humidity. Depending on the climate conditions where you live, your mileage may vary.
Here’s what you need to know. Whether presenting itself as a lovely soft powder or a mound of rock-hard crystals, the cleaning (dare I say nearly magical) properties of borax are not affected. If you end up with a giant crystalized rock-thing in the bottom of your laundry detergent, whack it with the end of a wooden spoon or some other implement to break it up then use it up as if it were completely liquified—crystals and all. Your laundry will still come out clean and lovely. If you are still bothered by these crystals, consider making smaller batches of laundry detergent that you will up more quickly.
To keep the box of borax powdery once you’ve opened it, don’t leave it in the box. Instead, store it in a plastic container with a tight-fitting lid or a sealed Mason jar. Or vacuum seal it if you own a FoodSaver or other vacuum sealing machine.
Hope that helps.