Some diseases attack the stem from the inside, including pythium and some insects bore into the stem and feed in the inside. I'd split open a stem and see what it looks like on the inside. This is no genetic defect, its diseased,
Blue .... Thanks very much
i really don't want to suggest it is any fault of DP
ive no idea what's going on here.
i have never re used soil ... And never stored soil.
bought new every time in sealed bags .
i will set about sterilising everything and spraying with insecticide .
ive been running the same feeding / temperature regime for 2 years .... There have been no sudden changes
I have something similar with my TD grow and I have a known calcium def.
How much was your harvest? Should I expect the same?