Please stop buying big plastic bottles of laundry detergent

[Warpy]

91. My grandmother made all her own soap

with rendered fat from scraps from a brother's butcher shop. She made a white soap that was mild enough for hands and faces plus a brown soap that would peel the hide off you if you tried to wash with it. The latter went into the washing machine, slices made with a pen knife. She didn't have any formulas, only a lifetime of experience starting in the late 1880s. I don't recall her using anything else but some aquamarine in the rinse water, to brighten the whites.

I'm afraid I still buy laundry detergent in plastic bottles, but the bottles are clear or white plastic, #1 or #2, those are the plastics that are recycled since they can take dyes later.

The above boiling water method would dissolve the powders more quickly. I don't think the peroxide, added as a color safe oxygen bleach, lasts through the process. I'd wait until the mixture was cool to add it or, preferably, just before using it to wash clothing. Heat and light both cause peroxide to break down, although you'd have to heat the 100% stuff to about 300F to get it to explode. Don't ask me how I know this.

Here's a laundry factoid, 3% peroxide right out of the bottle is great on fresh blood, takes it right out.