Answer: Digging and storing bulbs is one way to protect them from harsh winter weather, but some bulbs require a rest period (typically during the winter months), so digging them is also a way to ensure they are able to rest before putting on their display a second time. When bulbs become overcrowded they'll produce fewer and smaller flowers. Hyacinth's are bulbs that, if left alone, will naturalize. The size of the bulb has a direct relation to the size of the flowers they produce. Hyacinth's will multiply by developing little bulblets, but the bulblets won't flower for a number of years, so leaving them in the ground (or in their present containers) is a good idea - especially in your climate.
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