cybersix
Is it chlorosis really?
http://www.daylilies.org/ahs_d...
The causes include incorrect soil pH, nutrient imbalance, unsuitable soil moisture levels, root problems, overfertilization, disease, insects, and herbicide injury.
Over fertilization can be a problem as well as nutrient imbalance, so your fertilizer might help and it might not, it could make the problem worse. I would try it on one plant and see how it reacts.
