There is no "maximum" amount of sun per se since the strength of the summer sun also needs to be taken into account. For example, my MIL used to grow Nikko in NH on a west exposure; it got -weird I know- shade in the morning and afternoon sun- and the plant did well. However, down here on the South, the summer sun is way more strong and I have to provide afternoon shade for all hydrangeas, In general, I would look for afternoon sun conditions though as they do best with a break from the afternoon summer sun. The further south you are, the more important that is.

Annabelle and paniculatas down here get shade by 11am to 12pm or the leaves get sunscorched. But the leaves are more sun tolerant in areas north of me so these might be worth looking into. Panics grow fine in full sun in the northern states.

VS, its more compact clone Strawberry Sundae, Limelight, Little Lime, Quickfire, Little Quickfile, Pink Diamond and many others would be good choices. Check them out. Do not place them near entrance doors or where people get together as they all produce some scent that attracts flying insects.

Since you say you want mopheads, I would also plant a tree to =eventually= provide shade and then in a few years, I would try some mopheads placed so the tree gives them afternoon shade. Observe in the meantime, where do other people near put their mopheads and get ideas from that. Typically, eastern exposures and some northern ones will be best.

Luis

I have some in full sun and others in total shade, all do just fine. The only issue is that the one in the sun is huge, 6' high and probably 7-8' diameter, and in summer heat needs watering every day.

But hemlock140, you are located here in the PNW, yes?? Our summer sun is quite mild and and of much lower intensity than most places, certainly TN :-)) While we can get away with hydrangeas in full sun - with frequent watering during summer - I would not necessarily encourage others to do the same in hotter summer or more more southerly areas. It just puts too much stress on what are essentially woodland understory plants.

I ended up buying the vanilla strawberry. I got a really good deal on them too and they look super healthy! I have a plan to dig out the entire bed (we have solid clay soil) and replace with organic garden soil and compost. I do have another question (can you tell I have never grown hydrangeas? haha). Should I fertilize after transplanting? I know there are fertilizers like I used on my trees for transplant shock or should I use plant tone? I would love some advice from experienced hydrangea growers. I love these plants so much and I want to be sure that I do everything that I can to make them thrive. :)

I did plant two trees that one day will provide shade for my mopheads. I planted a weeping willow at the back corner of my yard that I am hoping will provide an area for a beautiful shade garden. Everyone said not to plant one and that I will regret it, but hey, live and learn. I find them stunningly beautiful and have wanted one since I was a little girl.

Rather than dig out a bed of clay and replace it with different soil, which will cause a "bathtub" which collects water and holds it, add the organic matter to the soil in the entire bed - lots of it - and mix well, and create a slightly raised or mounded bed. This will allow better movement of water. Plant a bit high and add soil around the root ball so it isn't exposed. Also, add an organic mulch to the entire surface such as shredded bark which will help maintain more even moisture and temperature. Especially in clay soil, you probably don't need fertilizers since it usually has really good nutrients, but certainly you don't need to fertilize any new plantings.

Sun will change over the season, between higher summer sun angle (up until June 20 or so, when it starts moving back towards the southern horizon.) So the sun is furthest south around Christmas, and days get longer up until the summer solstice (June 20 or 21). So see how it is in late June as well. In my more northerly garden, I get a larger change, but you will still get a fair difference. Also, tree leaves will change light levels, so I usually check near the beginning of the growing season, then when the trees leaf out, and also i late June to get a feel of light levels in my yard during the growing season.

Hydrangea paniculata plants like Vanilla Strawberry are lovely plants and less fussy than H. macrophylla, the big leaf types Blushing Bride, Nikko and LA Dreaming. Annabelle is really easy if it gets enough water and shade from hot sun. You have made a good choice to start with!