Spun Cotton and ? Fibre for plying

What fibres can I ply with spun cotton? I want the fibres to match in characteristics …ie shrinkage or washing reaction etc. I might knit a loose knit 3/4 sleeve top.

Another bast fiber or silk would work. If you’d like something wool, I’d use a superwash.

Thanks. What is “bast” fibre I want to ply my spin cotton with ?? Silk rayon bamboo. My query is which will wash and move in the same manner. I think I will skein and gentle wash
the spun cotton first. How hard will that be​:grimacing::grimacing:?.

Bast fibers are plant fibers. Cotton is a bast fiber

Bamboo, ramie, flax, hemp, jute, kenaf