Tops of new growth are all turning g yellow

I have a couple of purple haze that seam to be having a major problem. The tops of all the new growth are turning yellow. It started over the last few days.

I have them in 1 gallon pots in an organic composted soil . They are only about 6 weeks old.
Any help or ideas will be more than helpful

Have any pictures of full plant from the side in the pot?

First time I think ive seen sulfur deficiency easy fix mix a tablespoon of Epsom salt in a gallon of water for your next couple waterings (you can also give them a tablespoon of molasses to even out the cal mag) then 1/2 teaspoon each watering after

This looks like an iron issue to me. The appearance of yellowing among new growth is normal since the plant hasn’t matured chlorophyll yet, but your type of yellowing looks more like an iron deficiency.