Question
Thank you for taking my question, James.  Gill Borchardt, the shrubs expert, is on vacation until 12/31/13.  
I live in Kingman, KS (zone 6b), and I am planning on planting some Crape Myrtle shrubs on the west side of my house where they will get morning shade and afternoon sun.  However, I am trying to decide which cultivar of Lagerstroemia indica to plant.  I don't want to grow the crape myrtles into trees but keep them as shrubs.  I am considering either the Lagerstroemia indica 'Hopi' or the Lagerstroemia indica 'Victor Dwarf'.  There are mixed opinions about how tall and wide each of these shrubs will grow.  Most of the information that I have read indicates that the 'Victor' will not grow as large as the 'Hopi', but I like the hardiness of the Hopi more than the Victor.  Do you have any experience with either of these shrubs, or Crape Myrtles in general, from which you could give an accurate estimation as to how large each of these shrubs would actually grow?  Also, would I be able to control their growth with rejuvenating pruning without damaging their flower production?

Thanks,
Tim

Answer
Thanks for the question Tim,

I also live in zone 6b in Connecticut and I抳e not seen Crape Myrtle in landscapes here due to hardiness issues. I did however see one last year in what I think was on the boarder of Zone 7a and 6b just over the border in New York.  

The reason I抦 saying this is because I would be very cautious of USDA Zone maps and especially growers claiming hardiness. Unless you抳e seen Crape Myrtles in your area that have been successfully established, I抎 be wary. That being said though, I do think that in a sheltered area you could very well grow some specimens that might do quite well in your area. I would be mindful though of exposure to cold winter winds when making your final planting decision.

When it comes to selecting a particular cultivar, having never grown either one, I can only trust what the label professes as to their maximum height. I always keep in mind something my old Horticulture professor once told me about shrub labels, 揑f the label says 6-8?it really means 8-10?

Rather than 揜ejuvenation?pruning (removing up to two thirds or more of branches) I would suggest annual reduction pruning instead (removing shoots back to larger branch unions to reduce height). Reduction pruning will give a more natural growth habit and not look like it was hedge pruned.

I抎 be very encouraged to see you successfully grow Crape Myrtles in your zone and would inspire me to try my luck as well.

Best of luck

James