What are these yellow patches?

[Squash64]

A leaf on one of my giant pumpkins has started to get yellow patches on it.  What is the reason for this, is it serious and is there anything I can do?


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[Squash64]

[slyfox-mal]

it could be lots of things but id go with wet soil conditions and cool soil maybe locking in nutrients just stick with it and see how it goes

[brownowl23]

Mine are doing the same. gonna give em a feed tomorrows see if that helps

[chriscross1966]

Could well be magnesium deficiency... some Epsom Salts in the mix methinks....