Crepe myrtle trees (Lagerstroemia indica) are common ornamental landscape trees for both commercial and residential properties. The trees thrive in U.S. hardiness zones 7 through 9. Dwarf varieties are available for small landscaping spaces. The average height of the crepe myrtle tree is 15 to 30 feet with a canopy width of 6 to 15 feet. Small, delicate white, pink, red or purple flowers bloom on the tree from July through the early fall months. Trimming the crepe myrtle after the first blooms fade, and again in early fall, increases bloom volume. Blooms develop on new, current growth and last year's growth.
Stand on a step ladder to reach high branches on your crepe myrtle trees. Snip off tips of the top section of limbs with faded blooms, in the middle of July, with sharp pruning shears. Only remove 1/3 of the total limb length. For example, remove 4 inches from the end of a 12-inch long limb that has a faded bloom.
Return down from the step ladder. Repeat the first step with the remainder of the crepe myrtle tree.
Cut any offshoots sprouting at the base of the crepe myrtle tree flush with ground level.
Fertilize the base of the tree out to the drip line with 10-10-10 granular fertilizer. Use 0.1 pound per 100 square feet.
Water the crepe myrtle tree with 3- to 5-inches of water or until the ground is thoroughly wet but not soaked.
Repeat the first three steps around the middle of August, after the second set of blooms appear and fade.