The easiest mophead macrophylla to find would be Forever & Ever White Out. It grows to only 30x30" and reblooms Summer-frost (not sure if there is a compact white that begins in Spring?) They don't seem to be sold in large numbers, but should appear at places like Lowe's as they have the past couple of seasons. 3-gals of Forever & Ever products can sometimes be found at independent nurseries, but can run from $35-40.

If you are in a sunny spot you could try paniculatas Bombshell or Little Lime, and less commonly White Diamonds although I've seen it around this season. They would require little pruning and bloom on new wood so how much you prune is up to you. The paniculatas are most commonly sold in 3-gallon containers as well and are in the $40 price range.

Here is a link that might be useful: F&E White Out Hydrangea

Thank you Springwood. That looks like a great fit. Their dealer locator shows Lowe's as the only option, I wouldn't have thought to look their for something unique.

Are their any other cultivators that bloom white for part shade? The site I have in mind get dappled light all day and very little direct sun. Thanks!

I would wait two weeks to a month (or call) to check Lowe's. The ones around me just got in F&E original/blue/peppermint only.

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The most common white macrophyllas would be Mme Mouillere, Sister Therese, Regula, Snowball, Snow Storm / White King (rebloomer), Blushing Bride (the top pick for bloom count + hardiness), and Peace (double flowering).

There are not as many lacecaps but Princess Lace comes to mind, from the Royal Majestics series, also a rebloomer and I think Home Depot carried them.

White out! It is by far my favorite hydrangea---although very hard to find. I had to call my Lowes and ask for them to call me as soon as they got them in. I had them reserve 2 for me (I had bought 2 the previous season and loved them) and when I got there the guy said they had only gotten a few in and the rest were all gone.

Most Lowe's around me have White Out right now. They are in 2.5 gal pots and are $24.95 I believe. Some are a lot healthier looking than others - make sure you grab one with a lot of stems coming from the crown. Not sure whether or not I want one since they are so darn compact that some blooms get lost in the adjacent foliage! I'm sure Lowe's will have various F&E products throughout the summer. For example I found a 3-gal Peppermint in a promotional black deco pot, but there were only a couple of its kind.

Found some very nice F&E White-outs at the local Lowe's last night. Very excited to find something that is exactly what I was looking for- thanks everyone!

As of today, some Lowe's are also carrying PEACE (double-flowering white with yellow tint). Not nearly as attractive foliage as White Out (lighter green; kind of lanky leaves) but can look good in the right location/pot.