Hair colour too light, how do i fix it?

[Wroxie]

My hairdresser uses a shade called 'dark ash blonde' on my medium brown hair to keep the grey in check (I'm about 20% grey on one side and barely any grey on the other). It always looks great and perfectly natural when the hairdresser does it but I can't get to her now so I bought a box of 'dark ash blonde' at boots and it's too light. Looks like I have light brown hair that I've dyed a bit darker and the roots are growing out.

Can I just get a box of medium ash brown of the same brand and go again, or do I need to wait, or try to remove this colour first? If it matters, I applied it properly, just to the roots with a brush, left it on the roots for the majority of the time and then applied it to the rest of my hair for the last ten minutes or so. The length of my hair looks great and is still the right colour, it's just the roots that look weird.

(If it matters I used Schwarzkopf colour expert permanent colour - I know they use the professional Schwarzkopf range at my salon so I thought that at least the colours would be the same even if the formula was slightly different).

Hi, could you post a pic? Or what was the number on the hair dye box? Go by the number rather than the description of colour. For a dark ash blonde i would say you need a 6.1, but that may come out too dark if its box dye, so a 7.1 may be fine.

thanks - the colour is 7.1 actually :) I tried to take a picture but it doesn't really show up - it's definitely noticeable in person though (husband confirmed). Just wondering if I need to wait to re-dye with one shade darker, or if I need to try to use a colour remover first, or what.

I'm not a hairdresser so feel free to ignore. If I've read it right you've made your roots too light but are happy with the lengths? If so, then it's probably because the dye was too light and lifted the virgin hair at the root to a lighter shade, whereas it couldn't lift the dye that was already on the lengths as dye doesn't lift dye, if that makes sense. To fix I would get a shade darker (6.1) and just go over the roots to darken them, and not apply any to the lengths.