Over the years a number of papers have appeared which have evaluated the oils of clones of lavender (Lavandula angustifolia Mill.) and lavandin (L. x intermedia Emeric ex Loisel.) which were developed by industry or governmental agencies: Algeria, Bulgaria, France, Hungary, Italy, New Zealand, and the U.S.S.R. Many of the clones reported in these papers are proprietary, so we have begun our research on readily available clones. We have examined the essentiaI oils of twelve lavender and five lavandin clones from the nursery trade in the United States and Great Britain to assess them for future agronomic utilization. In order to increase the confidence of extrapolating from a laboratory situation to commercial field conditions, a plant of ‘Grosso,’ a leading cultivar of lavandin was also included in this study.
We are just beginning to assess the variation within a clone according to harvest. The oils of lavender, lavandin, and spike (L. latifolia Med.) have been analyzed from a number of different seasons and countries by investigators, and these papers provide some estimate of the variation to be expected.
Materials and Methods
Plants were grown for one to two years on a Sassafras sandy loam topped with 1-2 cm of sand in Camden, Delaware. Approximately 26 g of inflorescences with 50% of the flowers open were harvested at 7:00 A.M., E.S.T. Within two hours, all inflorescences were steam-distilled in a Neo-Clevenger of Moritz after Kaiser and Lang with the modification of Hefendehl. OiIs were dried over sodium sulfate, capped with nitrogen, and stored at 3°C until analyzed within 1-10 days.