I live in Egypt, the temperature outdoors ranges from 19-27 celsius during the mornings and drops to 10 celsius at night(I bring them indoors at night) . I don't think they were bleached by the sun as I've hardened them a couple of weeks ago, thank you!

looks like sun-scald/wind scald from not being hardened properly. Has it been very windy? They will be fine though.

Yes! It's been quite windy but I always bring them inside whenever it's windy. Do you think it's an iron defiency tho?

Not iron.

I agree that it looks like sun damage. The plants may have been too high on nitrogen before the transplant.

All fertilizer has nitrogen, phosphorous, and/or potassium in it, and is as a result NPK fertilizer (whether or not you know what the percentages of nitrogen, phosphorus, and pitassium are). What were the numbers for the N, P, and K?

People sometimes call other soil amendments fertilizer that aren't fertilizer, though.

Shule, by your definition I guess the soil micronutrient mix that I’ve been calling “Fertilizer “ for years is really something else. The typical trio on a standard fertilizer premix refers to N- P2O5- K2O. Any one can be zero as in urea: 45-0-0.

But Ali, the white leaves on your plants can result in as few as 20 minutes exposure to sun if plants have not been hardened off properly as Planterjeff noted. Keep them out of sun for a few days and then very gradually reintroduce them to it again.

Barrie, that's the definition I've read about on some occasions. I definitely think other nutrients are important, though, whether or not they're considered fertilizer, whatever that means. I'm just repeating what I've read. How did you find that P refers specifically to P2O5, and K specifically to K2O, rather than any form of phosphorus and potassium respectively? Wouldn't that make a lot of the NPK labels out there erroneous, since they use things like potassium sulfate, monopotassium phosphate, etc.? After looking it up a bit, it seems like they use K2O as a benchmark of sorts; so, the equivalent in K20 seems to be what's important (rather than the actual K2O content). Tell me if I'm wrong.

If it’s a different material it is just calculated back to P2O5 or K2O based on P or K content. However, not quite the same with lime where all lime materials are based on CCE (Calcium Carbonate Equivalent).

Just was my line of work. It’s hard for me to imagine that I’m now retired over 10 years and doing what most retirees do- Gardening.