I posted a link that has everything you need to be succesfull in you Hydrangeas planting in the related links box below.
they change colour with the soil pH level.
yes
In gardening
No.
Aqua blue.
Hydrangeas
Mophead hydrangeas (h. macrophylla) bloom in Chicago (zone5) in late May or early June, depending upon the site conditions.
Hydrangeas are not particularly dangerous to dogs. Dogs should not be eating weeds or flowers on a daily basis. If a dog overeats anything, it can be unhealthy.
No. They are flowers that grow from seeds.
Usually dryness at the roots.
Some do and some do not
Yes.