Septoria can survive on living tissue and plant debris but the odds of survival on metal is slim to none and it cannot create spores below 50 degrees so winter survival would be very limited if any. And since it is air borne any subsequent infections are likely from the air not the cages.

But if you want to clean your cages then the standard cleaning solution recommended for disinfecting pots, trays, and other garden equipment is a 1:10bleach solution - 1 part bleach in 10 parts water.

Dave

Thanks Dave.