Assuming you are "shearing" these plants, ie. a formal hedge treatment, then yes, August is the last month in the growing season during which this should still be done, in the north temperate zone.

+oM

why tom???

so it can set buds for next spring???

ken

So as to allow for the sheared foliage to not be desiccated by winter winds, etc. Pruning now (or earlier in the growing season) allows time for the wounding to be overgrown by slight new growth. Prune (of this type-shearing) any later in the year and you're apt to have lots of burning. Yews, etc.

+oM

who knew.. learn something new everyday ... ken

Please note all-this only applies to shearing-style pruning and has nothing to do with whole-branch removal, or for that matter, any other pruning style or technique.

+oM

HI everyone. I would like to thank you for the responses and the advice. Yes I just plan on shearing the plants for a better shape.

Thanks again

vince