Red Rocket and Dynamite are both true-red crape myrtles, and in full flower most people couldn’t tell them apart. They differ in the ways that matter once they’re planted: the shape and size they reach, how their leaves look, and how they handle disease. The better choice depends less on the flowers than on the spot you have and how humid your summers are.
Where These Two Red Crape Myrtles Came From
Before the late 1990s, “red” crape myrtles were really deep pinks or watermelon shades, and in hot sun they leaned even pinker. A gardener hoping for a clean red was often disappointed. In 1997 Dr. Carl Whitcomb introduced Dynamite, the first crape myrtle with true red flowers.1UF/IFAS Extension. Red Crape Myrtle Varieties Red Rocket came from the same Oklahoma research station, and the two became industry standards.2Lacebark Inc.. Lacebark Inc. Horticulture Research Station That shared parentage is why their flowers look so alike. Named varieties are grown from cuttings, which are genetically identical to the parent plant, so any healthy Dynamite should bloom and grow much like another.
Nursery tags take a little reading. Both plants are sold under trademark names with Whit code names behind them, and on labels Red Rocket may appear as Lagerstroemia indica ‘Whit IV’, its official variety name.3Brandywine Trees. Red Rocket Crape Myrtle: A Vibrant Landscape Choice4NC State Extension. Lagerstroemia indica ‘Whit IV’ A tag with “Whit” plus a Roman numeral points to a Whitcomb variety. A generic “red crape myrtle” tag may be one of the older pink-red types, so look for the actual name.
Size and Shape, Which Fits Your Space
Red Rocket reaches about 15 to 20 feet tall and 12 to 17 feet wide.5New Blooms Nursery. Red Rocket Crape Myrtle It grows fast and can push more than a foot of new shoots in a few weeks.6New Blooms Nursery. Red Rocket Crape Myrtle Dynamite generally grows more compact and rounded, while Red Rocket grows slightly taller and less wide.7Mortellaro’s Nursery. Crape Myrtle, Dynamite
In real yards, that sorts out simply. A strip beside a driveway or house wall favors the taller, narrower Red Rocket, and so does a row planted as a screen. A specimen in an open lawn suits Dynamite’s rounded crown, which looks balanced from every side. If you can’t be sure of your measurements, the more compact Dynamite is the safer pick for a smaller footprint. Leave roughly half the mature width between the trunk and a wall or fence so branches aren’t rubbing the surface, and space a row to allow for the full width, or the trees will crowd each other within several years.
Measure the distance to roofs, wires and walls against mature height before buying. A young tree can look small at purchase and outgrow its space within a few seasons. A plant that reaches 15 to 20 feet can grow into power lines that sit lower than you expect, and roots spread outward as the canopy does, so keep trees a sensible distance from foundations, septic lines and driveways.
Choosing the wrong size leads to “crape murder,” the yearly hard topping of a tree too big for its spot, which leaves knobby stubs and weak, floppy shoots. The right size up front means only light pruning of crossing or dead wood.
If any shaping is needed, prune in late winter, before new growth starts.
Flower Color, Leaves and Bark Through the Year
Red Rocket’s blooms may look slightly lighter in some conditions, while Dynamite keeps its deep red more consistently.8Mortellaro’s Nursery. Crape Myrtle, Dynamite Dynamite’s flowers are ruffled and fiery red.9Monrovia. Dynamite Crape Myrtle Red Rocket blooms from early July into September, about 100 days of color,10Trees.com. Red Rocket Crape Myrtle Tree and Dynamite blooms from early summer into fall.11Mortellaros. Crape Myrtle, Dynamite
Strong sun and heat can fade red petals as flowers age, so older blooms often look pinker than fresh ones on the same cluster. Full sun still gives the most flowers despite some fading. At the nursery, look at plants in bloom if you can, since a tag photo may be color-adjusted and light changes how color reads.
Red Rocket’s spring and summer leaves are deep wine red, darkening to purplish green.12Brandywine Trees. Red Rocket Crape Myrtle: A Vibrant Landscape Choice Its foliage contrasts with the flowers rather than blending in, which suits a mixed border with greens and silvers. Dynamite’s leaves emerge crimson in spring, turn dark green, and finish with orange and red fall color.13Monrovia. Dynamite Crape Myrtle That green backdrop makes its summer flowers read as brighter. Both drop their leaves in winter to show smooth, peeling bark.14Monrovia. Dynamite Crape Myrtle15Mortellaro’s Nursery. Crape Myrtle, Red Rocket
Dynamite’s orange-red fall leaves give a second season of color after the flowers finish, so favor it if fall color matters to you. Also think about what’s behind the tree: red against brick can blend, while red against green or white stands out.
Disease and Pest Resistance
Cercospora leaf spot is a fungus that makes brown spots on crape myrtle leaves, followed by yellowing and early leaf drop. In a Georgia field trial, Dynamite was among the varieties with the most leaf spotting and early leaf drop.16HortScience. Susceptibility of Crape Myrtles to Cercospora Leaf Spot in Georgia In humid summer climates, expect that Dynamite may lose leaves early in some years. The damage affects appearance more than it threatens the tree’s life, and the tree leafs out again the next spring.
Spotted leaves that yellow and drop in mid to late summer point to disease rather than fall color. If your summers are damp with frequent rain or dew, weigh this more heavily when choosing Dynamite.
You can lower the odds. Plant in full sun with room for air to move, water at the soil rather than over the leaves, and rake up fallen spotted leaves in fall. A spot with morning sun dries leaves faster, which helps either variety. Fungicide is rarely needed for a home tree.
The trial did not single out Red Rocket, so its disease risk is less documented, not proven lower. Ask local nurseries how it performs in your area.
Crapemyrtle bark scale is a sap-feeding insect that leaves white felty patches and black sooty mold on trunks. In a potted-plant test, Dynamite held fewer than 100 egg-bearing scale females, far below some other crape myrtle species.17PubMed Central. Feeding Preference of Crapemyrtle Bark Scale (Acanthococcus lagerstroemiae) on Different Species
To catch scale early, look for white crusty specks in bark cracks and branch joints. A black sooty coating on bark or leaves is a warning sign. Scrubbing trunks with soapy water can knock back a light infestation, and it’s worth asking your local extension office before using systemic insecticides.
Cold Hardiness and Where Each Grows
USDA hardiness zones map how cold winters get, based on average lowest winter temperatures, and you can look up yours by entering your zip code in the USDA map tool. Dynamite is listed as hardy in zones 6 through 9.18NC State Extension. Lagerstroemia indica ‘Whit IV’ Red Rocket is listed for zones 7 through 10.19Mortellaro’s Nursery. Crape Myrtle, Red Rocket In colder zone 6 gardens, Dynamite is the safer bet.
In zones 7 through 9, both are listed as hardy, so cold won’t decide between them. Gardeners in zone 10 have only Red Rocket listed. Both need summer heat to bloom well, and cooler, short summers mean fewer flowers.
A zone number describes the coldest typical winter, not unusual cold snaps, so a plant at the edge of its range can still be hit. Microclimates matter too: a spot against a south-facing wall may run warmer than the rest of your yard. At the cold edge, a hard freeze can kill stems back to the ground. Crape myrtles often regrow from the roots and still bloom on new wood, so wait until late spring before pruning dead-looking stems, and mulch the root zone before winter in colder gardens.
Planting and Care for Either Variety
Dynamite does best in full sun and well-drained soil.20Mortellaro’s Nursery. Crape Myrtle, Dynamite Crape myrtles tolerate many soil types, acidic or alkaline.21National IPM Database. Pest Management Strategic Plan for Crapemyrtle in the South Once established they are very drought tolerant, though occasional deep watering helps during long dry spells.22Mortellaro’s Nursery. Crape Myrtle, Dynamite
Pick a spot with at least six hours of direct sun. To check drainage, dig a hole and fill it with water; if it still holds water many hours later, choose another spot or raise the bed. Avoid low areas where water pools after rain.
For planting, dig a hole twice as wide as the pot and no deeper, and set the top of the root ball level with the ground. Spread mulch a few inches deep, kept off the trunk. Plant in spring or fall to avoid summer heat stress.
The first summer, water deeply once or twice a week, soaking the whole root ball rather than sprinkling. Water less often as the tree roots in over a season or two. Soggy, poorly drained spots lead to rotting roots.
Wilting or curling leaves in midday heat that don’t recover by evening are a sign of thirst. Otherwise, most gardeners need to water only in extended dry periods.
Heavy nitrogen feeding gives leaves at the expense of flowers. Snipping spent flower clusters can encourage more bloom, and too much shade is a common reason for poor flowering.
Do Bees Visit Red Crape Myrtles
In a Georgia bee survey, Red Rocket was among the crape myrtles bees visited least, and bee numbers differed by flower color group.23CAES Field Report. What’s Your Flavor? Bee Preferences for Crape Myrtle Cultivars If feeding bees is a goal, a red crape myrtle shouldn’t be your main pollinator plant. It’s a note about one survey on bee visits, not a finding that the tree harms pollinators.
You can still garden for bees around it. Pair it with lighter-colored crape myrtles or other summer flowers, and plant summer-blooming perennials, ideally native ones, beneath it so bees have something to feed on while the tree is in bloom.