community of dyers

I'll start by recommending you use pure single-hue unmixed Procion MX dyes for color mixing, when possible, rather than mixing together colors that are already mixtures of several other colors. It's less confusing and can give you brighter, richer colors (though you can also produce subtle colors that way, too, of course).

A big advantage of using the unmixed Procions for your color mixing is that lots more people have used those specific colors, and therefore can tell you more about how they act together. Premixed Procion colors, such as imperial purple or hot pink, can work well together, but I can't tell you what they'll do, since I didn't happen to buy those particular mixes. I suspect you'll need to add a navy blue, but I'm not at all sure. To see which of the Procion MX dyes are unmixed pure colors suitable for use as mixing primaries, see my page, "Which Procion MX colors are pure, and which mixtures?".

You don't have to use black as a toning color if you don't want to. Using black to mix colors is a shortcut, but one that has some drawbacks, so not everyone does it. I generally don't, myself. To get very dark colors, use a navy blue as one of your mixing colors, and use more dye than you would use for paler colors. (See "How much Procion MX dye should I use?".)

Cobalt blue is an excellent navy blue to use in mixing deep rich purples. I also like Dharma's "Strong Navy", although it is a mixture; it contains a different navy blue, reactive blue 9, combined with red MX-5B. You don't need to buy both cobalt and strong navy; either one will do. I like mixing either of these navy blues with violet MX-2R, or either red MX-5B (Dharma calls this one 'light red') or red MX-8B (fuchsia) to make deep purples. I also like ProChem's Boysenberry, which is an unmixed color just exactly the color of crushed berry juice, but you can't buy that one from Dharma or Jacquard, and it's not quite dark enough on its own for what you're trying to do.

Combining any color with the gray background of the wrap will produce a subtler, toned-down color, as compared to dyeing on white fabric.

-Paula