Here's a breakdown of what to do:
1. Understanding the Color Wheel & Tones:
* Blonde Hair: Often lacks underlying warm pigments (reds, oranges, and yellows) that are necessary for a natural-looking brown. This is especially true for bleached blonde hair.
* Why Green Can Happen: Dark brown dye usually contains blue tones. If you put a blue-toned dye directly on blonde hair, especially if it's very light blonde or has a cool undertone, the blue can dominate, leading to a greenish cast.
* Filling the Hair: The key is to "fill" the hair with those missing warm tones *before* applying the dark brown dye.
2. Steps to Successfully Dye Blonde Hair Dark Brown:
* Choose the Right Shade:
* Avoid ashy/cool browns: These have a lot of blue and green, which you want to avoid for the first step. Look for browns with "warm," "golden," "caramel," "chestnut," or "auburn" in the name.
* Consider going a shade lighter than your target color: Going a shade lighter will allow the filler to be more prominent and create a more natural base for your desired brown.
* Fill the Hair (Crucial Step):
* Options for Filling:
* Red or Orange-Based Filler: Use a semi-permanent or demi-permanent hair dye in a red, copper, or orange shade (depending on how light your blonde is). Choose a shade that is *slightly* lighter than the brown you eventually want to achieve.
* Protein Filler: This helps repair the hair and also adds a base tone.
* Application: Apply the filler color evenly to all of your hair, following the instructions on the product.
* Processing Time: Follow the recommended processing time on the filler product.
* Apply the Dark Brown Dye:
* Choose the Right Shade: Now you can select your desired dark brown dye. If you have used a filler and your hair is now darker, you can choose your target shade. If you only used a protein filler, choose a shade with warm undertones.
* Application: Apply the dark brown dye evenly, making sure to saturate all of your hair.
* Processing Time: Follow the instructions on the dye box.
* Strand Test (Highly Recommended):
* Before you dye your entire head, do a strand test on a small, hidden section of your hair. This will allow you to see how the colors will look and how long you need to process them.
3. Important Considerations:
* Hair Condition: Blonde hair, especially if it's bleached, can be porous and damaged. It's important to condition your hair well before and after dyeing it.
* Demi-Permanent vs. Permanent:
* Demi-permanent: Depositing only, less damaging. Washes out over time (24-28 washes). A good choice for the filler step.
* Permanent: Lifts and deposits color. More damaging but lasts longer.
* Fading: Dark brown dye can fade over time, especially if you wash your hair frequently. Use color-safe shampoos and conditioners to help prolong the color.
* Root Touch-Ups: Be prepared for root touch-ups as your hair grows out.
* Professional Help: If you're nervous about doing it yourself, or if your hair is severely damaged, it's best to consult a professional hairstylist. They can assess your hair's condition and recommend the best approach to achieve your desired color.
Example Scenario:
Let's say your hair is platinum blonde, and you want to go to a medium chocolate brown.
1. Filler: You might choose a light copper or reddish-blonde demi-permanent dye as your filler.
2. Dark Brown: After filling, you would then apply your desired medium chocolate brown permanent or demi-permanent dye.
In summary, dyeing blonde hair dark brown is possible, but it requires careful planning and execution. Filling the hair with warm tones is crucial to prevent unwanted green or muddy tones. When in doubt, consult a professional!