BloomstruckBloomstruck is an all around fantastic hydrangea. From its array of colors that change depending on the pH of the soil to its higher than average heat tolerance, this hydrangea really packs a punch! Bloomstruck is incredibly disease resistant, especially to powdery mildew, and has strong stems for cut flowers. This hydrangea does prefer morning sun and afternoon shade, however it will tolerate more sun in cooler climates.