The ‘Double Dynamite’ Crape Myrtle is a popular and distinctive ornamental shrub or small tree. This variety stands out due to its vibrant flower color and extended blooming period, making it a favorite for adding dynamic beauty to various landscapes.
What Makes Double Dynamite Unique
The ‘Double Dynamite’ Crape Myrtle (Lagerstroemia indica ‘Whit II’ PP#23,914) features intense, deep cherry-red flowers. These vivid blooms appear continuously from mid-summer through early fall, offering an extended period of color unlike many traditional crape myrtles that bloom only once.
The plant reblooms continuously on the same flower panicle, ensuring a consistent display of vibrant red flowers for over 100 days. Its rich green foliage emerges with a reddish tint in spring and often transitions to burgundy or orange-red in the fall, providing multi-season interest. This cultivar also exhibits high resistance to common crape myrtle diseases like powdery mildew and leaf spot. It typically grows to a manageable size of 8 to 10 feet tall and wide, with an upright, rounded, and dense growth habit, making it versatile for various landscape applications.
Planting Your Double Dynamite Crape Myrtle
The ideal time for planting ‘Double Dynamite’ Crape Myrtle is during the dormant season, either in the fall or early spring, though it can be planted any time of year in suitable growing zones (USDA Zones 7-10). Select a site that receives full sun exposure, meaning at least six to eight hours of direct sunlight daily, to maximize its blooming potential. While it can tolerate some shade, flowering will be diminished in less light.
This crape myrtle thrives in well-drained soil and is adaptable to various soil types, including average garden soil. To prepare the planting site, dig a hole twice as wide as the root ball, ensuring the top of the root ball is level with or slightly above the surrounding soil. After placing the plant, backfill with soil, gently loosening any bound roots, and water thoroughly to settle the soil and eliminate air pockets. Apply a 2-3 inch layer of mulch around the base, keeping it a few inches from the trunk, to help retain moisture and regulate soil temperature.
Ongoing Care for Double Dynamite Crape Myrtle
Consistent full sun exposure is crucial for vigorous growth and abundant flowers. During its first growing season, deep watering once or twice a week is recommended, allowing the top few inches of soil to dry out between waterings. This practice encourages roots to grow deeper, enhancing the plant’s drought tolerance once established.
Once established, the ‘Double Dynamite’ Crape Myrtle becomes drought-tolerant, requiring supplemental watering only during extended dry periods or extreme heat. Check the soil regularly, watering when the top 2-3 inches are dry. To support vigorous growth and continuous blooms, apply a balanced slow-release fertilizer (e.g., 10-10-10 or 12-4-8) in early spring as new growth appears. Spread the fertilizer evenly around the drip line, away from the trunk, and water it in thoroughly.
Pruning for Health and Bloom
Prune ‘Double Dynamite’ Crape Myrtles during the dormant season, typically in late winter or early spring, before new growth begins. This timing minimizes plant stress and encourages vigorous new growth, as crape myrtles bloom on new wood. Pruning goals include shaping the plant, promoting air circulation, enhancing bloom quality, and removing dead, diseased, or crossing branches.
To avoid “crape murder” (excessive topping), focus on selective cuts rather than severe heading back. Remove small, weak branches, suckers emerging from the base, and any rubbing branches. Thinning the interior canopy allows better light penetration and air flow, leading to more blooms and reduced disease risk. For a tree-like form, select three to five strong, well-spaced main trunks and remove lower branches to expose the attractive bark.
Common Issues and Solutions
While ‘Double Dynamite’ Crape Myrtles are known for disease resistance, gardeners may still encounter some common issues. Powdery mildew and Cercospora leaf spot can affect crape myrtles, though ‘Double Dynamite’ exhibits high resistance to both. If these issues arise, ensure good air circulation through proper spacing and pruning to help prevent their spread. Fungicidal treatments can be applied in severe cases.
Aphids are among the few pests that may occasionally bother crape myrtles, leading to sticky honeydew and sooty mold growth. Minor aphid infestations usually don’t cause significant problems, but larger populations can weaken the plant. Natural solutions like horticultural oil, neem oil, or insecticidal soap can manage aphid populations. Environmental stressors like prolonged drought can reduce flowering, so supplemental watering during dry spells is important.
Landscape Design and Uses
The ‘Double Dynamite’ Crape Myrtle is versatile in landscape design due to its striking appearance and manageable size. Its intense deep red flowers and multi-season foliage make it an excellent specimen plant, serving as a focal point in a garden bed or lawn. The upright and rounded growth habit also lends itself well to mass plantings, creating vibrant hedges or colorful privacy screens.
It can be integrated into mixed borders, adding height, structure, and continuous summer color. For smaller spaces or patios, the ‘Double Dynamite’ Crape Myrtle thrives in large containers, bringing its dazzling blooms closer to living areas.