Many natural hair colors contain indigo, which transforms into a deep blue over 72 hours. During this time, it needs enough moisture to fully develop its color. Typically, you’ll:

1. Mix the hair color powder with water to form a paste.
2. Apply the paste and leave it on for about one hour, allowing the plant pigments to bond with your hair.
   

This process is usually correct—the problem often arises after you rinse out the dye.

• If you blow-dry your hair right away, you may dry out the indigo prematurely. Without sufficient moisture, it can turn purple instead of blue. When this purple hue combines with henna’s orange tones, your hair may end up looking red.
• Solution: After rinsing, let your hair air-dry for around 72 hours. This extended drying time allows the indigo to fully develop into a deep blue, helping avoid any unwanted red tones.

Even if you air-dry your hair, it might still turn red if it’s highly porous. Hair porosity refers to how easily your hair absorbs (and loses) moisture.

Signs of High Porosity

• Hair sinks quickly when placed in a glass of water.
• Hair lacks natural shine and loses moisture quickly, especially in dry climates.

Why High Porosity Causes Red Tones
Hair with high porosity doesn’t retain moisture well. If the air is dry, the moisture needed for the indigo to develop properly can evaporate too soon, leaving purple or red undertones.

Solution:

• Instead of regular air-drying, wrap your hair in a towel to hold in moisture as much as possible.
• Avoid frequent shampooing. If the plant pigment gets washed out too often, it can leave you with an unwanted reddish color.
• Try using a damp towel around your hair to supply extra moisture without needing to immerse your hair in water.

If you’ve had issues with red hair after using Soft Black, Dark Brown, Brown, or similar darker natural dyes, consider these tips:

1. Air-Dry for 72 Hours: Allow the indigo to oxidize fully and develop into a deep blue.
2. Maintain Moisture: Use a towel wrap if your hair dries out quickly. Keep hair hydrated to give the indigo time to bond properly.
3. Limit Washing: High-porosity hair loses pigment quickly. Space out your shampoos or use gentler washing methods.
4. Check Your Hair Porosity: If you suspect high porosity, try additional moisture treatments before and after dyeing.