Depends on variety.

Mine started out with base growth. I went to cut back "dead" branches and saw that they are now growing leaves.

I'd leave it for a while longer to see what happens.

Exactly!! How it should be treated now depends on what kind of hydrangea you are growing. Panicle hydrangeas flower on new seasonal growth so can be cut back hard. Same with smooth or Annabelle type hydrangeas. Bigleaf hydrangeas bloom primarily on the previous year's growth so you do not want to remove anything that could have the potential to produce flowers. Stems that fail to produce any leaves can be removed at the base but wait until you are sure no more leaves are being produced before removal.

You don't have to do anything if you don't want to. New growth will cover the old growth later in the summer. Based on the lack of dead flower heads, I'm guessing it didn't bloom much last year. And if it's a mac, which I think it is, it probably never will in NY.

What is a mac? it had a few flowers last year but not covered w blooms like hydrangeas i see i didnt plant it so i dont know what kind it is

A mac is a Hydrangea macrophylla.

H. macrophylla do quite well in the tropics of New York - usually known as NYC and Long Island.

Gardengirl is correct, panicle hydrangeas can be cut back hard. I cut my limelight hydrangea tree form back hard in the fall. It barely looks like anything is left. But it comes back and blooms beautifully. I do the cut back in fall so branches are not broken by heavy snow, sleet or ice. I found that out the hard way.

debra

This is a macrophylla/mop head hydrangea which blooms on old wood; it's buds would be visible now. It could be an Endless Summer which blooms on both old and new wood. It was a rough winter and a lot of hydrangeas lost their buds but wait a little while longer before you cut out any deadwood. It's highly likely you won't see any blooms this year unless it is an Endless Summer and then you'll get maybe a few blooms later in the season,

This is not a panicle hydrangea which unlike mopheads bloom only on new wood and can be cut back hard in the spring, If you want a lot of guaranteed blooms every year, buy a panicle hydrangea since bad winters don't affect them. Unlike the mopheads they love sun although they bloom well in as little as 2 to 3 sun hours in my yard, Mopheads usually do not do well in the afternoon sun; they usually only want morning sun,

Below is Bobo a dwarf 3 foot panicle hydrangea. I've tried them all and this by far is the best for both blooms and sturdy branching. This only gets three hours sun. The blooms turn pink as the the season progresses,

@Anita D'Ammora if the bloom was red/pink or blue, it's almost certainly a mac. it will only bloom from stems that survived the winter. Some claim to bloom off new growth, but, in my experience, it's really iffy. If the blooms were white, then it almost certainly blooms on new growth, so you can prune whatever old stems you want now and it will have little effect on blooming.

Because you only had a few blooms, my guess is it's a mac. The white ones usually produce a lot of blooms.

Bigleaf hydrangeas - macs - also come with white flowers so color alone is not necessarily a determining factor. And a lot of new wood bloomers are quite successful in colder zones. The Endless Summer series is one of the less reliable

Thank you to everybody who responded. Special thanks to jan beth who identified the type of hydrangea and how it is meant to bloom. very useful information. is there any such thing as a hydrangea native to america? im trying to incorporate natives into my garden and might just remove these if there is a suitable replacement.

Oakleaf (Hydrangea quercifolia) and smooth hydrangea (H. arborescens) are the two US native species.

btw, just from the OP's photos alone, there is no way an identity can be confirmed!

As gardengal48 said, those are 2 natives. Annabelle (smooth hydrangea) now has an improved version with less floppy stems called Incrediball. I have Annabelle and a hard rain will put many blooms on the ground. I might try Incrediball myself. I'm not a mophead fan....fussy and unpredictable blooming. As I said, your's MIGHT be an Endless Summer but that's a guess only because of the huge# of them out there. We had some thatcame with our house...I gave them away. Great to see more people going native.

From online: " Incrediball is an improved version of the popular Annabelle hydrangea, with strong, sturdy stems that do not flop over and extra-large blooms. Incredibly hardy, even in the harshest winters, this US native hydrangea is perfect for mixed borders, small gardens and patio containers."