This is kind of one of those "it depends" on where it's going to be planted situations. Depending on the variety of smokebush, you can get a height and spread anywhere from 4-6' to 10-25'. Does well in sunny location with well drained soil.

Summer Wine Ninebark has a height and spead of @4-6' and does well in full sun to part shade.

I don't have any smokebush, but do have a few varieties of Ninebark (Dart's Gold and Diablo) scattered around the yard and they're good performers - mine are a little too young yet to have the peeling bark which gives them their winter interest.

Looking at the Google images for both, the ninebark seems to be a shrub with a little more substance; the smokebush lighter and airier. Sometimes my preference in shrubs runs to something I can see as opposed to something I can see through.

Physocarpus 'Diablo' will make a large shrub with purplish brown leaves. P. 'Summer Wine' is supposed to be smaller, though mine is not. All cultivars of purple smoke (and you do want a named cultivar) tend to have considerable winter dieback, even in zone 6, and look best if they are cut back to stubs (coppiced) in spring. That gives you a huge (up to 8 feet)flush of upright new growth with intensely purple red leaves.

Physocarpus = deer food
Smokebush = deer resistant

I had a 'Diablo' at a previous house and the deer loved it. I was so disappointed. Here, I have a purple smokebush out in full southern sun. Not a single deer nibble, looks stunning right now and it isn't even in bloom.

Here, it is behind an iris pseudocorus (yellow flag)

{{gwi:223728}}

If of interest, I do a lot of experimenting for deer resistance (and drought) and put updates in my gardening blog.

Cameron (North Carolina)

Here is a link that might be useful: my gardening blog (focus on deer)

Stooling a smokebush here produces a flopping flowerless octopus of no charm.

Interesting, bboy, how different parts of the country cause plants to behave so differently. Stooling a purple smoke is the only way to get a handsome plant here.

I love Ninebark - mine always look good. I have Summer Wine, which is blooming now, Diabalo, which will bloom this year for the first time, and three Coppertina. The last is somewhat of a problem because I situated them in a spot that is too shady, so they are not reaching their full color potential. I have noticed no watering problems. Deer do like Diabalo, so I moved him from far away to next to the dog's pen and have had no further snacking. They taste Summer Wine, but don't seem to like it much and it is such a strong grower the damage never really shows - I just wish the flowers lasted longer.

I have 2 Diablo Ninebarks. Deer are regular visitors to my yard and snack on a lot of my plantings, but have never bothered the Ninebark. However last year, powdery mildew became a problem with them. One Ninebark is situated in perhaps a less than ideal place where airflow, or more correctly, lack of it and just 4 to 5 hours of full sun might be the problem. I cut it back severly this year to try to get a handle on the mildew. The other Ninebark is in a very breezy spot with full sun and good moisture, but is showing a few spots of mildew.

Lucinda, all these above responses aren't helping you choose, I am sure. Sometimes you just have to jump in with both feet and "Go for it!" Good luck with whatever you choose!

It's interesting that the deer forgo the 'Summer Wine' but will munch on 'Diablo'. Who'd have guessed?

Lovely color combination, Wits. I am thinking that the lacy smokebush is for the perennial bed while Ninebark is more appropriate to a shrub border.

Now I am off to ascertain the distinction between "coppicing" and "stooling". Valuable feedback, thank you!!

Predictions of deer browsing behavior are like those of hybrid rose disease susceptibility: there is too much variation from one time and place to another to come up with truly reliable lists. It is true that there are certain plants that they seem fairly consistent about passing by, but unless those are all you want to grow it still always boils down to effectively fencing them out.

I have (2) Smokebushes, "Royal Purple" and "Velvet Cloak".

"Royal Purple" grows faster than anything I've ever grown, but I had to chop the main braches down to 1-3 ft tall each of its first (3) winters ... to get the bush to spread out at all.

Now my 5 years in the ground "Royal Purple" is about 12 ft tall and 8 ft wide.

"Velvet Cloak" is much more of a spread out plant, much more bush-like than "Royal Purple". It doesn't grow quite so voraciously, and its smoke is more wine-colored. The one I have I've had for 3 years or so, and its now about 4 ft tall X 4 ft across. I've never had to cut it back. I'd recommend it.

I have two Coppertina's. They're stunningly beautiful! Mine are planted full sun. The one is approx 7' tall and a good 5' across. They are very showy colour wise. In the spring they look coppery and lovely. Then as we get farther into summer it turns purple with it's beautiful pink flowers. I'm so pleased with mine. I do keep it pruned and tidy as they can look untidy otherwise. I keep it mulched with pine needles and shredded bark. This has helped to achieve colour change in the leaves, and hold moisture. I receive many compliments on this shrubs colour.

I love both shrubs but find my ninebarks easier to grow and look better during the entire growing season than my smoke bush. I am with Cheryl Coppertina is a wonderful plant. I like all the ninebarks and barely do a thing to them but a little compost at their feet when I remember.