Crepe myrtle (Lagerstroemia indica) is an important shrub and small tree in Texas landscapes and across the southern United States. In 2014, wholesale sales of crepe myrtle exceeded $65 million, and there are a wide variety of cultivars, differing in size, flower color, bark color, and disease and pest resistant (Wang et al., 2016). Crepe myrtle tolerates difficult conditions across many soil types and is tolerant of low fertility, alkalinity, drought stress, heat stress; in some cultivars, it is also resistant to powdery mildew (Arnold, 2008; Cabrera, 2004; Dirr, 2009).
A cross of Red Rocket® crepe myrtle (‘Whit IV’) and ‘Sarah’s Favorite’ crepe myrtle resulted in a crepe myrtle with dark foliage, ‘Chocolate Mocha’ (Knight and McLaurin, 2010). ‘Chocolate Mocha’ was used as a parent to create five more cultivars of dark-foliaged crepe myrtle with different flower colors (Pounders et al., 2013). These new cultivars have black-purple foliage that is darker than ‘Chocolate Mocha’ and more resistant to fading in summer sun, along with a range of flower colors including red, white, and pink. Cultivars include Ebony Embers, Ebony Fire, Ebony Flame, Ebony Glow, and Ebony and Ivory, and they are sold commercially under the Black Diamond® (BD) brand under the names BD Blush (Ebony Glow), BD Pure White (Ebony and Ivory), BD Crimson Red (Ebony Fire), BD Best Red (Ebony Flame), and BD Red Hot (Ebony Embers) (Pounders et al., 2013). Each crepe myrtle in the series exhibits the dark foliage and has a similar mature size, but the cultivars vary in flower color and growth habit.
New ornamental plants are always welcome, but landscapers and homeowners face mounting challenges of decreased water availability, contamination of surface and groundwater from fertilizer runoff, and the impact of pesticides on our environment (Zlesak et al., 2015). Of these, limited irrigation water is especially important in Texas, with a potential water shortage of 5.6 million acre-ft per year in 2030 and irrigation water needs above 3.5 million acre-ft per year (Texas Water Development Board, 2017). The use of pesticides is decreasing as customers seek insect and disease control methods with minimal environmental impact (Harp et al., 2009; Zlesak et al., 2015). For north-central Texas, crepe myrtle is an important landscape species because it continues to provide color and landscape value when drought stress is at its most severe (July-August) (Cabrera, 2004; Chretien and Harp, 2017).
This study was conducted to evaluate the landscape performance of Ebony crepe myrtle cultivars in north-central Texas (U.S. Department of Agriculture Plant Hardiness Zone 8) under low-input conditions.
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