Yet, all of a sudden they've been killed. This disease can infect flowers in the fall or young succulent shoots in the spring. Young shoots are especially vulnerable when predisposed by frost trauma just before temperatures exceed 61 degrees F. and if one tenth of an inch of rainfall occurs at the same time.
Fire blight causes young, tender shoots to wilt, turn brown and black, and die.
It also produces cankers that cause twig and branch dieback. Control infections by pruning out and discarding blighted branches. Bleach solution is highly corrosive to metal, so if you use it, be sure to rinse your shears and re-oil them before you put them away.