Answer: One of the most common Rose of Sharon health issues is "Flower Bud Drop." Your shrub may be in bud or full bloom and then the next day the buds/flowers have fallen off. To avoid this, the soil moisture must remain constant; it can't fluctuate excessively between dry and moist. This is why a rich, organic moisture retentive soil is recommended.
To reduce evaporation and maintain a cooler soil temperature, apply a 3-inch layer of mulch under the shrub. This should curtail any future bud drop issues.
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