Went up the lot late yesterday afternoon, to do some 'damned good watering', as it hasn't rained for at least a couple of weeks, and find the blasted garlic is developing rust spots. Damn. Serious infection can inhibit or completely stop the bulb growing, and it's an air-bourne fungus affecting alliums (so can affect/infect onions and leeks too).
Just read up about it this morning, and somebody suggests pulling off/cutting the affected leaves and getting rid of them, making sure you wash your hands and implements (such as scissors or shears used) so the infection isn't carried over to over plants, and the garlic should still be able to photosynthesise and continue developing! I'll try it!
'They' also suggest it's helpful to water during the day, rather than in the evening, so the plants have a chance to dry out rather than remain damp overnight, because the 'rust' likes damp warm air.
Some of the garlic leaves are yellow as well, and you think: "Too much water? Too little?" Gawd.
Also some bastard insect has been enjoying the onion leaves. Bastards.