Sunflowers track the sun during the day, moving from east to west from dawn to dusk respectively. However, at night, they move back towards the east in anticipation of the sunrise despite a lack of sunlight. It is known that the circadian clock plays a role in regulating this heliotropism that increase plant fitness. Seeds from a heterozygous mutant plant were planted in an attempt to find a homozygous recessive mutation of the LUX gene that represses day-phased genes in the circadian clock of Arabidopsis thaliana. Using DNA extraction, PCR, and restriction digestion, no plants of the twenty samples were found to be a homozygous recessive mutant. Future research includes performing the experiment again with more samples, and once a mutated plant is found, planting the homozygous mutant plant in a field to observe any phenotypic differences from typical behavior. Understanding how a disrupted LUX gene affects the circadian clock and solar tracking may help future research in improving plant adaptations to increase plant productivity on a molecular level.