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Joshua tree (Yucca brevifolia) is a visually dominant plant of Mojave Desert. We documented unique directional orientation of its flower panicles in Joshua Tree National Natural Landmark in southwestern Utah. We first became curious after observing directional orientation of cactus flowers in the hyper-arid Atacama Desert of northern Chile. Because much of the Atacama lies south of the Tropic of Capricorn, the sun is always in the north. The flowers maximize exposure to sunlight by orienting themselves to the north. Although not a cactus, we hypothesized that the Joshua tree might utilize a similar strategy. Because the Mojave Desert lies north of the Tropic of Cancer, we hypothesized that Joshua tree flower panicles might orient themselves toward the south. We measured the orientation of all flower panicles on 50 random plants. The flower panicles grew primarily at the tips of branches that were oriented to the south. When branches with flower panicles were not oriented in a southerly direction, the flower panicles themselves tended to bend or tilt toward the south. This strategy maximized exposure to solar radiation. The strategy minimizes energetic costs of translocating photosynthates from the leaf rosettes to the flowers. Residual warmth in the flower panicles also provides a thermal reward for moth pollinators that emerges shortly after sunset. In the context of ecological restoration, when transplanting Joshua trees, one should ensure that the side of the plant that faced south in its natural setting, is also oriented to the south in its new setting.