G'day,
The Fallschirmtruppe at first used white chutes and later used camo ones (green, red-brown & tan). Both were used on Kreta although the majority were by far white.
I too have read many accounts from the Allied side saying the chutes on the supply canisters were colour coded but I am not aware of German accounts mentioning this. Certainly the canisters themselves were marked to indicate contents and the unit it belonged to.
I should say I am not an expert on German parachutes. You might try posing your question on the following forum where a few 'experts' hang out.
www.wehrmacht-awards.com/forums
Go to the site and then proceed to the Fallschirmj
äger forum.
Cheers,
George.