its a beast.. it wont be easy to beat it back ... in terms of the work you will need to do annually

i planted one about 6 feet from the front of my old house.. in a few years it was up above the gutters .. and working its way to heaven ... i just cut some of it down to about 6 inches ... and then each year cut more back ...

but with no insult to the root mass ... it was usually back over the gutters in a year or two ...

i moved.. seemed easier at the time.. lol ...

check into rejuvenation pruning ... and go at it .. and then decide if you want to move to get away from it.. lol ...

ken

https://duckduckgo.com/?q=rejuvenation+pruning+smokebush&t=ffcm&iax=videos&ia=videos

I'm not sure I understand what you mean by "make it proportionate to the rest of my garden" but you can keep the shrub to a smaller overall size by coppicing or stooling. Coppicing is a pruning technique of cutting back trees and shrubs to the ground, often on an annual basis. Stooling is similar but cutting back to a predetermined height (rather than to the ground).

This is done in late winter or early spring, just as you see the buds on the stems begin to swell. If you Google "coppicing Cotinus coggygria", you will find numerous websites outlining how.

I did not want the smokebush to grow to a height where it would not look like it fit the garden where the junipers would be the sentry of the garden.

When do you hard prune time of year. May have to learn technique of stooling as suggested.

I prune them early spring. i’ll try to find a pic from at the end of the season to show you how tall it gets here.

Here are a few I found.

this is in July approaching 6 feet

later in October well over 7 feet (I did shape/shorten this with no concerns as it was the end of the season)

Another one just to give you an idea of how they grow vertically...on the right

and this is how I wish they would stay... Love the rich color

If you do cut it down a foot or or more will it grow more scraggly. That is something I wanted to avoid my church's garden high profile

Yes I believe it would.

Here is a link I came across while researching the best way to prune these. It really helped me understand its growth rate/pattern. I hope it helps.

http://www.rathersquare.com/2014/08/how-not-to-prune-a-smoke-tree/

Thanks for all your input much appreciated

You’re welcome and good luck.