The Jacquard Tie Dye Kit includes excellent Procion MX dyes, plus soda ash, plastic squirt bottles, gloves, and rubber bands - everything you need to get started except for the shirts!
What is Cellulose?
Cellulose is the main fiber that plants are made of. All plants contain cellulose. Fibers that contain cellulose include the most familiar clothing fibers: cotton, linen, and rayon. They also include more uncommon plant-based textile fibers, such as bamboo (which is usually rayon), hemp, lyocell (Tencel), and ramie. The only plant-based textile fiber that is not cellulose (or a mixture of cellulose and lignen) is the soy protein fiber sold under the name "Soy Silk".
Dyes for Cellulose Fibers
There are several different types of dyes that work well on cellulose.
Cellulose is a polymer, a long molecule made from thousands of repeating simple sugar molecules. Here's a chain of five and a half of them....
Notice how how glucose sugar molecule is shaped like a ring; in this image, the red balls are oxygen atoms, the gray balls are carbons (the backbone of life), and the hydrogen atoms are shown in white. Five complete glucose rings are visible in the chain above, but there are three thousand or more in each long, thin cellulose molecule.
As described in the Encyclopedia Britannica article on cellulose, 90% of the mass of cotton is cellulose, while wood, which is stiffened by another large molecule, lignin, is about 50% cellulose.
The best reference I've found is the 1995 book Cellulosics Dyeing, edited by John Shore. It can be purchased directly from the Society of Dyers and Colourists, in the UK, for £32 plus shipping (ISBN 0 901956 68 6).