The cultivation and application of Pseuderanthemum palatiferum, a plant found in the latter half of the 1990′s in northern Vietnam, was studied at a total of 12,829 households located in the city center and suburb of Cantho city. The frequency of the households cultivating the plant, the plant′s population and age, recipients, purposes and amount of the dosages were surveyed in interviews with households. Second, growth of the plant at an experimental farm of Cantho University was observed. Only 1.1% of the total households cultivated the plant. However, more (p<0.01) households in the city center cultivated the plant than those in the suburb. More households in the city center cultivated greater populations of the plant. The city center households dosed the plant not only for treatment of human diseases, but also for the prevention and treatment of animal diseases. The frequencies of the dosage and the amount of each dose were more for treatment than for prevention, and more for human diseases than animal diseases. The dosages were more in the city center households. The results of the field study would suggest that cultivation of the plant had been spread from the city center to the suburb, and its dosage had widened from the purpose of treatment to prevention of diseases, and the recipients from human to animal diseases. The plant observed could grow very fast and bloom, in the same way as the growth in northern Vietnam. The easiness of its planting and the earliness of growth would have helped the spread of its cultivation and application in the Mekong Delta region.