Mineral nutrients return to the soil when leaves and branches periodically fall to the ground and decay, thereby completing one of nature’s most important cycles. Prior to leaf abscission, some of the nutrient elements (including nitrogen, potassium, and magnesium) are released from their bound form in protein, chlorophyll, and other molecules and transferred from leaves to the plant’s growing tips for reuse. Because mineral relocation is in progress when older leaves turn yellow, gardeners can help their plants conserve nutrients by not removing discolored leaves for several days, until the
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