There have been a few posts about itchy dogs recently so yes def something extending our usual allergy season!!
Hibiscrub - use it very diluted as it's quite drying. A few drops in less than half a bucket of water will be enough to slosh 8 legs and paws! If you have one, use a cat litter tray to make a foot bath - much quicker. Do dry thoroughly afterward as wet paws = itchy paws. This is my no 1 coping strategy for my itchy dog and it's a godsend
You can use Piriton - but see what your vet says about dosage.
I do give spinach from time to time but haven't found it's ever really made much of a difference. I use the raw frozen stuff, as it's already in handy blocks, and chop very finely whilst it's still partially frozen.
My other miracle stuff is Dermacton. HTH
Kindness is the language which the deaf can hear and the blind can see ~Mark Twain