Penny hate to see you go without some sort of answer. I don't know what the major differences are other than hardiness and size. The penny mac is considered tender for this area so we don't see many of them.

Color for both is going to be based on soil alkalinity so if your in the so-so area your going to have an ugly bleached out looking pink or blue.

Regarding size, all the penny macs in this area are pushing the 5-6' range and the ES 4-5'. I think your probably going to have to do heavy pruning to keep either at 3'.

Good luck.

I knew the blooms were blue in acidic soil and pink in alkaline... but are you saying that the pH also determines how vibrant the color is? If that's the case, can't I just add some aluminum sulfate (for blue) or whatever to the soil to make the color deeper?

I read this on a hydrangea website:

"One can rarely change the intensity of a color (how strong or pale the color is). The intensity develops for a number of reasons: the heredity of a particular hydrangea variety, weather conditions (hot or cold, humid or dry), health of the plant, and possibly other natural factors."

That's why I thought the deepness of the color was independent of the soil alkalinity.

Here is a link that might be useful: Hydrangeas color change reference

My Penny Mac has done a lot better for blooms and hardly any wilt compared to Endless Summer but that may be due to where they are both planted too. Size-wise Penny may be 3-4 feet tall while ES is less than 3'.

Here is PM with the majority of the blooms facing the side that gets most of the sun.

The soil pH will affect the color and the shade of color. Closer to neutral, the pinks and blues will be lighter/fainter while very alkaline or very acidic soil will produce a deeper shade of pink or blue. The exact shade that you get will be based on all of the factors listed: soil pH, genetics, weather. etc, Genetics, for example, will make some plants like Nikko Blue produce very deep and nice blues, but provided it is planted in acidic soil. If the soil is not very acidic, blooms have been known to be light blue.

both are not a dark blue but a light blue. Es is much more a stronger grower and has more flowers than PM. Both for me are 5 foot plus so neither will meet your size requirements-perhaps mini-penny will do.

I'm not looking for "dark blue" (like navy or something). I just want some deep, rich color. Here is Monrovia's sample photo for Endless Summer: http://www.monrovia.com/img/plants/256/d/1731-endless-summer-hydrangea-close-up.jpg

The flowers look kinda washed out and blah.

Here is one of Monrovia's sample photos for Penny Mac:

http://www.monrovia.com/img/plants/4205/d/2375-penny-mac-hydrangea-full-shot.jpg

I wouldn't call that a "dark pink" but it is a "vibrant pink"... you can tell it is pink.

I've seen some good shots of Endless Summer too... but Penny Mac seems to be more consistently the one with nice rich color. That's why I was asking about difference in bloom color between the two.

It looks like it depends on the person for which one does better -- one person saying Penny Mac has been better and growing no more than 4 ft and another person saying Endless summer is better and they both get 5 feet. Decisions... decisions... *sigh*

hcmcdole -- you should let your hydrangeas out of jail! :P Anyway, where are your Endless Summer hydrangeas planted? Are they getting more sun than the Penny Macs? And how is the color of the Endless Summer blooms compared to the Penny Mac color? Same?

I'm thinking what I might do is go ahead and get an Endless Summer to fill one of the two holes. Based on how it does, I'll decide whether to get a Penny Mac for the other or just another Endless Summer.

Both will grow similarly in size and stature..

Differences:

- PM has smaller sepals than ES. Both can grow similarly-sized flower heads (up to 12"+), but PM's will appear to have more individual flowers on the head and hence appear more "intricate" than ES.

- both are affected equally by PH, so "vibrance" depends strictly on soil conditions and NOT genetic predispositions.

- PM seems to produce both thinner and more numerous stems than ES, possibly affecting the supposed mature size difference.

Opinion: I'm slightly happier with my PM so far since it produces more stems than my ES's... Much less scraggly -looking!

Yeah, I have to keep them in jail so my dogs don't totally destroy them going after squirrels.

Endless Summer is next to a very large, very tall oxydendrum (sourwood) which probably drinks all the water but then I have a Snow Queen, Incrediball (so far not that incredible), Lilacina, Hanabi, Emile Mouillere, and a PInky WInky around the same tree that don't seem to be as affected as E.S. They all get plenty of sun while I think E.S. and E.M. get more shade than the others.

P.M. has both large florets and smaller ones on different stems. Is this normal?

Here is the dinky E.S. last month.

I know I'm reviving an old post, but it's mine...so there :P

Anyway, I ended up waiting until this year to get my new hydrangeas. I got two that actually had labels and both are supposed to be Penny Mac. They're doing well and look more like I expected (definitely not another Annabelle). However, I noticed that the leaves look different on the two. One has darker, rounder leaves -- do the leaves differ a lot between different specimens of the same cultivar?

Here's a picture

They do appear different. Time will tell.

How did those two that looked different turn out?

Very late to this party but since this thread has been resurrected, it might be helpful to offer some clarifications.

Color intensity in bigleaf hydrangeas is almost exclusively due to genetics. Some cultivars just produce paler, lighter colored flowerheads and that will not change due to soil chemistry. Light exposure can have some bearing but generally only to fade or washout the coloring.

Both ES The Original and Penny Mac are pale colored. You will never achieve a rich dark blue color with either despite soil conditions, as it is just not in their genetics. OTOH, cultivars like Mathilda Gutges or Enziandom have very intense coloring and will produce very deeply blue flowers in appropriate soil chemistry.

And size is relative :-) I have seen 8' tall ES hydrangeas in my area but then dieback due to cold winters is pretty much unheard of here! There is no set magic number at which point a plant stops growing. If it continues to live it will continue to grow, barring pruning or cold damage.