Crepe Myrtle won't bloom

I have had a crepe myrtle for 5 years now, and it has yet to bloom. Any idea what I might be doing wrong?
It's in full sun, is watered regularly, and appears very healthy judging by the foliage.
Any help would be greatly appreciated.

Hey rikerbear, I found this info...hope it helps

Planting: The plants should be spaced 18" apart in the landscape. When potting a Whiskey Barrel you should place 3-4 plants in each pot you make.

Light: They grow best in full hot sun anywhere in the U.S. up to about 1/2 or 50% shade.

Soil Type: I have not found a soil where Lagerstroemias won't grow including all commercial mixes.

Watering: Crape Myrtles do well in any moisture situation except dry desert climates where you must water more often.

Fertilizing: Fertilize Lagerstroemias during the growing season with any of the water soluble fertilizers such as Peters or Miracle Grow. Any analysis about every 2 weeks works well. Osmocote type fertilizers also work well.

Spacing Between Plants: Place or space plants 12" to 14" apart in group plantings, borders around buildings or homes, and mass ground cover plantings(see our photos from the Worlds Fair for examples)

Blooming: Crape Myrtles flower on "new" growth made in the spring so even the smallest plants flower the first season you get them.

Perennials: These Lagerstroemias are Pennsylvania grown to provide maximum cold hardiness in all areas of the country. If your area is colder than a Zone 5 you should grow them in Containers or Hanging Baskets. Plants should be protected when the temperature gets below -10 to -20 F. If plants are planted in the ground they are more cold hardy.

Pests: The Mini Crape Myrtles are almost insect and disease free although you may see aphids from time to time. We spray with over the counter sprays like diazinon, malathion, & we use rose disease sprays(for mildew) that are readily available.

Pruning: We have bred these Lagerstroemias to be very self-branching with a tremendous amount of New Growth so you will see many thousands of flowers each season.

Where to Use these Patented Lagerstroemias: In Landscapes, as border plantings around buildings for summer color or as mass ground cover plantings like I did at the Worlds Fair. In Containers, they make excellent Hanging Baskets(10" to 12" Baskets or larger fiber baskets), excellent containers in large clay or plastic pots, or put several in a half whiskey barrel for a traffic stopping specimen plant.

Patents: Patents: These Patented varieties have been selected from thousands of crosses and over 20 years of hybridization and breeding. Much like the tree crepe myrtles they are very strong plants and can survive even the most primitive conditions.

Thanks DC...obviously mine is not a Lagerstroemias of the variety spoken about in your info. I have altered the fertilizer regiment. It's really the only thing I haven't tried.
I'm beginning to wonder if it just doesn;t get hot enough for long enough here to activate the 'bloom' gene.
Thanks again for posting the info. :-)

I dont think your zone is a factor, people here have them all over the place and they bloom. My mom has one and she does nothing to it, in fact Mom is known for killing flowering plants except weeds.
The only way Ive found to for her to keep plants alive is if I plant them for her and she leaves it alone. LOL

Hmmmm.....I'm almost beginning to believe this isn't a crepe mrytle at all, but some mislabeled plant my partner brought home by mistake. LOL