Red stem is often the first sign of a nitrogen defciency. This can be because you need to add Nitrogen or you need to adjust your PH so that your plant can actually absorb the Nitrogen.

Almost all clones have red stems.. this is not a problem at all.. But when you have a plant that has a green stalk and it is 3 weeks old and you still want to veg it for 3 more weeks and you notice that the stalk is starting to go red and spread to secondary growth, then you should take some action...

Eventually the plant will/can turn completly red and all the stems will become spindley and brittle...

ALWAYS check your PH first...

and now you KNOWM

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