Article: When they start to yellow because of cooler temperatures and less water, they are ready to cut. Be gentle to avoid harming the bulb. Dry it and store it in a cool dry place, just as you did before you planted the bulb. It should be kept cool and dry for 6 to 8 weeks before you plant it again.

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Start to water the plant less as you get close to removing the bulb. Make sure you remove and store the bulbs before the first frost, and before temperatures reach 50 degrees Fahrenheit (10 degrees Celsius). Cut the leaves back to 2 inches above the bulb. Remove the bulb and roots from the soil. Clean the bulb with water.