From what youβre describing, this looks like a classic potassium (K) deficiency moving upwards, but itβs not a true deficiency β itβs caused by potassium lockout from salt build-up in the medium.
π Symptoms you mentioned:
Brown, crispy edges on the leaves
Leaves drying out and falling off
Starts from the lower leaves and moves upward
β‘οΈ This is not caused by light, shading, or pests, but because the plant canβt properly take up potassium due to high salts in the root zone.
β
What you can do to fix it:
1οΈβ£ Water with low EC solution (or plain water + CalMag) to reduce salt levels in the medium. Not a full flush, just enough to lower the stress.
2οΈβ£ Feed with a more balanced nutrient solution, avoiding heavy Bloom boosters which add extra salts and worsen K lockout.
3οΈβ£ Measure the EC of the runoff:
2.2β2.4 mS β likely salt lockout
3.0 mS β full flush may be needed
4οΈβ£ Add a small dose of Alga Mic or another K supplement without extra nitrogen to help recovery.
π‘ Bottom line:
Not normal leaf shedding
Not a light problem
Not pests
Itβs potassium lockout from salt build-up, starting low and moving up
what medium youβre using (soil or coco), ?