I have three that are about 10 ft. tall, after 20 years. All are trained into a tree form, which means that there are no branches within 4-5 ft. of the ground. They do not spread by suckers and the canopy is about 8 ft.wide. All H. paniculata's require some sunlight or a very brightly lit location to produce blooms and to thrive.
I have only staked them while training into tree form. If you want a multistem shrub, staking is probably unnecessary.
Rb

All the branches on my Pee Gee Hydrangea meet the trunk on
top at one point. I've had if for two years and it has eleven "rings" on it's slender 4' trunk so it may be quite
mature. It bears masses of
flowers and I remove some so it doesn't bend over. Should I stake it? How can I encourage the trunk to thicken?

Our families old home plantation has a pee gee atleast 80 years old about 30 feet tall

My Pee Gee is about 10 years old. Every January I prune it back to 4 main branches about 18'-20' long. It always comes back looking like the picture that I'm going to attempt to post. It's about 5' tall each year.

Here is a link that might be useful: PG

at my ancestral home there is a pee gee that is 80 to 100 years old and is 30 feet tal! very old and a single trunk!

Woooow, post a picture if you get the chance!

There's also one like that in the neighborhood I grew up in. It's next to a 2-story 1920's style house, and the tree goes all the way up past the rain gutters! I will try to get a pic of it on my way to work in August.

at the family reunion will get a pic-my Aunt thinks my great grandmother planted it around 1920

I see this thread was renewed this year - I'd be interested in seeing the photos of the pee gees. Am thinking of purchasing one, but not sure if I want it to get 30 ft tall in the space I'd like to plant it.

While this shrub has the ability to get quite large - see George's (ego45) photo above - it is not going to happen in any great hurry. Most of the photos you see of very large PG's are of plants that are 30-40-50 or more years old. 8-10' is a much more typical size in most gardens although in ideal conditions it will grow larger. And since paniculatas bloom on new growth each season, they are very easy to prune to keep to a more manageable size. PG (or pee gee - cultivar name 'Grandiflora') is known for producing very large inflorescences, maybe the largest of the species, and by pruning and thinning on a routine basis, these can be encouraged to an even larger size.

Thanks, gardengal48! Just the information I needed.