gitk will not start on Mac: unknown color name "lime"

I've installed git on a mac via brew install git. When I try to start gitk I get the following error:

Error in startup script: unknown color name "lime"
    (processing "-fore" option)
    invoked from within
"$ctext tag conf m2 -fore [lindex $mergecolors 2]"
    (procedure "makewindow" line 347)
    invoked from within
"makewindow"
    (file "/usr/local/bin/gitk" line 12434)

It appears that my Mac doesn't have a color named lime.

Can I add a lime color to the environment, or is there a better fix?

The git version is 2.7.0, and the Mac is running Yosemite 10.10.5

You can check your version of Tcl/Tk by running wish and using the command info patchlevel. It appears that git 2.7.0, Tcl/Tk 8.5.9, and OS X 10.11 El Capitan do not work well together.

I solved this problem by doing brew cask install tcl, which installed 8.6.4, and gitk works now.

I also found the same problem with exactly the same version of git and OSX. As a temporary workaround I suggest you to do the following:

cp /usr/local/bin/gitk /usr/local/bin/gitk.bkp
vi /usr/local/bin/gitk

and replace all occurences of lime to any color you want (I used #99FF00). Here is the vim command:

:%s/lime/"#99FF00"/g

EDIT: Please follow Keith B answer for permanent fix.

@Konrad Thanks for the help!! Although the answer is correct, please be aware that your command

:%s/lime/"#99FF00”/g

contains two different quotation marks, which will def. throw an error if copied & pasted.

So in order to go through with it, I had to do:

cp /usr/local/bin/gitk /usr/local/bin/gitk.bkp
vi /usr/local/bin/gitk

And inside vim:

:%s/lime/"#99FF00"/g

If you don't want to use Caskroom, follow this:

$ brew install tcl-tk
$ brew link tcl-tk --force

I was face same issue in ubuntu system. Then i flow below step to resolve issue.

1. open /usr/bin/gitk file in any text editor

2. search 'lime' keyword in file

3. replace 'lime' to 'green' with all in file

4. save file changes

5. try again gitk then it works