|My new yaupon's leaves are turning black. Am I overwatering?|
It could be soggy soil conditions or also damage from certain weed killers which are also found in some weed and feed fertilizer combos. Dig down a few inches and feel the soil to see if it needs watering. Water when it is getting a little dry to the touch. It is better to give a good watering on an infrequent basis than to keep the soil wet all the time. If you get the soil moisture right the plant should recover. If the problem was herbicide it may recover in time and with good care although some branches may be lost.
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