Next time you are at the store, check the Mexican food section.
Klass
is made with food colors (yah, it will dye) and dried fruit juice
(smells yummy), and has an authenticity in hues that Kool-Aid can't
match.
For a mini-hank of .2 ounces, we used 1 tablespoon of vinegar to a package. The vinegar is needed to bond the food dye to the wool yarn.
We sampled Sandia, Jamaica, Mango, Naranja and Tamarindo.
Below is a photo of Klass on the upper row and Kool-Aid on the bottom row so you can compare colors.
Top row from left: Mango, Naranja, Sandia, Jamaica Klass
Bottom row from left: Orange, Soaring Strawberry, Black Cherry, Tropical Punch Kool-Aid
Mango and Naranja are the color of fresh squeezed orange juice (both are almost the same color).
Sandia is a less cotton candy version of Soaring Strawberry Kool-Aid.
Jamaica is slightly darker and richer than Black Cherry Kool-Aid.
And Tamarindo is exactly the color of a Fortune Cookie (need to knit a Fortune Cookie, anyone?)

My favorite color isn't orange but the Mango and Naranja are very
attractive. Unlike Kool-Aid orange, which almost screams "I am orange
Kool-Aid" on any wool yarn, Mango is a mysterious shade.
Jamaica
is a good (but slightly more expensive) substitute for Black Cherry.
Either would be useful to tone or dull other colors used in small
amounts.
Four points:
How to choose a base yarn.
When do you need vinegar?
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