Naturally dyed color will last the lifetime of the garment and beyond with proper care.
To extend the life of the fibers and deep colors, hand wash in pH neutral soap and hang to dry. Naturally dyed fibers made of cotton and linen can be machine washed in cool water and a gentle detergent. Tumble dry on low. Avoid bleach, baking soda, and vinegar when washing. Do not machine wash and dry wool.
Do not dry or store fibers direct sunlight. Avoid wearing deodorant with baking soda while wearing naturally dyed items. Avoid contact with iron rust and strong acids like lemon juice, wine, or vinegar, which can shift or bleach natural color. If the garment comes in contact with a strong acid or alkaline substance, immediately soak the garment in cool water and pH neutral soap to neutralize the reaction. Hand wash and line dry.
Take care when spot treating stains and test an area of the fabric first. Dilute pH neutral soap in water and allow to soak on the spot before washing and drying. Multiple gentle treatments and washes may be needed for stubborn stains like oil.