Are the tips also white? If I would have to guess without pictures, I would say it's a Mg or Zn deficiency. Maybe even a combination of both. Get some pictures and fill the new sticky troubleshooting form out and someone will be able to answer.

Oh and the reason I think it could be either of those is because Mg deficiencies tend to yellow and white starting at the bottom and eventually dying and working its' way up. Zinc deficiencies usually have white areas forming on the tips and between veins. Soil is probably really alkaline. Need to check that Ph. If so, you can bury some galvanized nails in the soil. They have Zn and help aid to give that micronutrient to the soil and plants.


P.S. Your welcome! (for getting back to you so quickly! )