I've found it really does make a difference if you plant in the autumn. If the weather is too wet to get onto the soil, plant the cloves in 3 or 4" pots and overwinter in a tunnel, greenhouse or cold frame, before planting out before they get too big for their pots. This year I planted in Feb I think, under weed excluding fabric, and the garlic looks quite big, so I expect they would have been monsters if I'd planted 3 months earlier. These were cloves I had saved from my biggest plants last year. I'm looking forward to lots of garlicky meals this winter.