Should I cut the dead wood from hydrangea plants?

My grandmother says no, that is what brings next years blooms.

I cut my plants back to about a foot tall every fall...and in the spring they come back like gangbusters !

I don't drastically cut mine back, because they are old (20+ years) and about 4 feet tall now. The larger the plant the more blooms you have.

To prune, when the plant starts to bud out, cut out any dead brittle wood that didnt produce leaves, and any dead wood left above where it's leafed out. Worked for me every year so far!

No they help support the flowers

I've researched this ad infinitum on Google, and it's confusing. Experimenting with my own hydrangeas, they will not bloom if cut all the way down to the ground in the Fall. I cut them back each Fall to 1-2 feet and mulch the base with either mulch or shredded leaves. That way they will bloom the next summer. Clearly some varieties will bloom if cut to the ground, so perhaps a season or two of experimentation on your part will give you the answer.

It depends on the variety. Some form flowers from old wood so you would only trim off the old wood once the leaves bud off of it in the spring. Sometimes mine will grow all the way up the old wood and then some of the old wood I will cut down completely because no new growth formed. It is crucial to know what variety you have because if you cut down the old wood before it buds, it will not bloom that year.

I have climbing hydrangeas that are at least 10 years old. The greenery is full and healthy but they only produce one or two flowers each year. I am thinking of just getting rid of them at this point.