Natural Dyeing with Kitchen Scraps: Onion Skins and Avocado Pits

Before synthetic dyes were common, people colored cloth with whatever grew around them: roots, bark, leaves, and yes, kitchen scraps. Natural dyeing has made a comeback because it turns trash into color and produces soft, earthy tones you simply cannot buy in a bottle. The two easiest starting points are yellow onion skins, which give warm golds and ambers, and avocado pits, which yield dusty pinks and blush tones. Both are free, and both work on natural fibers like cotton, linen, silk, and wool.

Start by saving your scraps. Onion skins pile up quickly if you cook with onions, and avocado pits can be frozen until you have enough. For a small project like a set of napkins or a tote bag, a few cups of onion skins or three or four pits will do. You will also need a large pot you do not mind staining, a wooden spoon, and a mordant. Mordants help the color bind to the fiber, and the simplest option for beginners is alum, available in the spice aisle or online.

Preparing Your Fabric and Dye Bath

Wash your fabric thoroughly to remove any sizing or oils, then simmer it in water with a spoonful of alum for about an hour. Let it cool in the pot, then wring it out. This step is what keeps your color from washing away later. While the fabric soaks, make your dye bath. For onion skins, cover them with water in a pot, bring to a simmer, and cook for about an hour until the water is a deep amber. Strain out the skins. For avocado pits, chop them roughly, simmer for an hour or more, and strain. The liquid often looks brown or murky at first, but it shifts to pink on the fabric, which is part of the fun.

Add your damp, mordanted fabric to the dye bath and simmer gently for an hour, stirring occasionally with your wooden spoon. The longer it stays, the deeper the color. Turn off the heat and let the fabric sit in the bath overnight for the richest result. Keep in mind that natural dyes are subtle. They will not give you neon brights, but they will give you soft, layered tones that look like they came from a meadow.

Rinsing, Caring, and Experimenting

When you are happy with the color, rinse the fabric in cool water until the water runs mostly clear, then wash it gently with a mild soap and hang it to dry in the shade. Natural dyes fade over time with sun and repeated washing, so hand wash these pieces when possible and store them away from direct light. You can also shift colors by changing the mordant or by dipping fabric in an iron bath, made by simmering rusty nails in water, which deepens and saddens the tones.

Once you get comfortable, branch out. Red cabbage gives blues and purples, turmeric gives bright yellow, and black beans give a surprising blue-gray. Keep notes on what you used and how long you simmered, because natural dyeing is part science and part happy accident. Every batch will be a little different, and that is exactly what makes it worth doing.