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I tried my hand at r/homemaking, but I didn't get any answers so I was suggested to try here. Thanks for any insight.

I like hunter green but it's not popular anymore. I've been trying my hand at dyeing plain white sheets to get them that color, and I did get some good advice to mix dark colors to get the dye really dark. However, while that DOES work initially, I can get the sheets that color once it comes out of the bucket, once I wash it it all rinses out :(

I follow the package directions exactly, I use hot water, I let it soak for at least the minimum time, I add salt (the sheets are cotton), and like I said it will get to that color, but the dye won't stay in the fabric.

Does anyone have any advice how to keep that dye in the fabric? IDK what I'm doing wrong. Thanks again for any help.