Q.My Hydrangeas Were Full On Brown Rust Like Spots On The Leaves This Past Summer And The Blooms Were Not Very Pretty This Season.
What do I need to do to prevent this next spring when they sprout back out in the green folliage, short of digging them up and sta rting all over again. the leaves were full of brown rust like spots and blooms were not pretty also. do I need to dig them up and start again. I live in Sandhills of NC where it is hot and humid all summer.
It is hard to diagnose leaf spot accurately and suggest fungicides/bactericides with no sample pictures of how impacted the whole shrub is as well as several leaf closeups. Spotting can be caused by fungal or bacterial infections. While a normally humid environment will promote spore germination, overwatering and watering the leaves will also help spread these diseases. So make sure you only water the soil directly instead using drip irrigation or soaker hoses. Sprinkler stations should activate from 6-8am so the leaves do not spend the night wet. Use clean sanitation practices to also help. In addition to the previous suggestions, discard all plant debris (leaves and spent blooms) in the trash; replace old mulch with new mulch; do not allow plants to touch each other so prune when there are no flower buds in order to increase air flow; open the inside of the shrub to more sunlight, etc.