What is this?

They’ve had purple stems since they were tiny seedlings like popped out of the ground purple. But it just recently started and wondering if anyone knows what to do.

Magnesium def

What are you feeding?

Dyna grow foliage pro. I was thinking mag def but just wanted some more experienced options.

A break down of the grow would help better identify the issue. Grow medium feed and schedule. I'm thinking you should check your pH levels. Droopy leafs are suspect root bind or watering issues may be afoot.

The purple is most likely just the strain, but the yellow to browning spots in the vain area's means you have a mag deficiency! So, add 1/2 tsp of Epsom salt whether you are feeding or just watering, per gallon of feed or water!

I've seen it a million times on a million different plants, very normal since first grow 50 yrs ago. Some plants,same strain,same lot, have turned entirely purple, very rare , mot talking about purple strains. (these are my experiences ).