I will be honest, I donβt think the app is great with the watering part. I still have to check the soil myself first. I feel like over time it will work well once it learns your watering habits.
Removing them encourages new growth and keeps the plant looking healthy and pest free. French hydrangeas are not a fan of direct sunlight especially in the afternoon. You might want to find a shadier place to put them - morning sunlight and afternoon shade.