Do you know what kind of hydrangea you have? And what are you expecting when you are looking for pink color? There are some hydrangea that are pink at their peak, and others that bloom one color (blue, white, or green) and then fade to pink with age. Yours looks like the latter--to me it looks like they're white or green blooms turning pink as they dry out, which is what some hydrangea just do naturally.

As they fade, some types turn much pinker than others. The ones on the left look pretty nice to me, actually. My hydrangeas (endless summer, which are blue in June/July, then fade to green and finally pink) turn pinkest when they have a non-stressful summer--enough moisture that they don't dry out frequently and enough sun to turn them rosy. I then cut the nicest dry ones and bring them in, where they stay that way for up to a few months.

Here are two links: a pink blooming type (which I don't think you have),

http://www.hydrangeashydrangeas.com/images/pia_shrub.jpg

and one that has faded to pink in fall (which is probably what you have)--3rd picture on this link.

http://sentimentalquilter.blogspot.com/2012/10/fall-colors.html

Hmm. I have noticed some hydrangeas here will also skip the pinks (or other intermediate colors) and go directly to greenish-pinkish or even brown too. Some paniculatas (not your type of hydrangea) such as Vanilla Strawberry for example, will not achieve pinks (let alone its famous magenta) here on year 1; it goes from white to green with pink splotches. I am waiting to see in future years that improves as it gets "older". Other older paniculatas have had this issue so I am now trying earlier blooming ones to see if they get pinks earlier in the summer.

Another example of this problem happens to me regularly with Little Limelight. In its current location, it only gets bright shade so it stays green and does not transition to white. Instead of turning white after a few weeks, it remains green and at the end of the growing season, it turns green-pinkish. Funny though. It turns out that I prefer seeing the green blooms all the time now. So with limited sun, Little Lime bypasses white and goes green-pink. I assume lack of enough sunlight is the cause since LL is in bright shade (actually, the shrub is located just a few inches from getting sunlight!) and in a protected location where it gets sufficient moisture.

So, over here, I 'blame' this issue on very high summer temperatures, insufficient sunlight and-or drying winds. If the blooms turn brown and there is no fungal issues, I assume there is a problem with winds drying the plant too much or soil moisture issues doing the same. If the plant skips a color but the sepals do not turn brown, I assume the plant needs more sunlight. In SD, your temps are not as bad so I would check the other conditions: a location that is protected from winds but still provides morning sun thru 11am (more or less) and provides evenly moist soil conditions at all times (or obviously, as best as you can). Dry-wet-dry-wet-dry issues will make the plant first abort the blooms in the summer and they will turn brown. If the moisture problem becomes more pronounced then the leaves will also be affected and show symptoms.

I do not know what fungicide you used or if it may have interfered with the bloomage but insecticides/fungicides can do all sorts of things. However, I think if the fungicide had affected your blooms, it would have affected the leaves too.... but these look just fine in you picture.

Some hydrangeas improve bloomage after 3 years so give it a try for that long and replace it if it still does not perform well.