Our agronomic studies have shown that earlier seeding was beneficial, particularly with the later maturing varieties, in obtaining higher essential oil and seed yields and in increasing the probability of producing acceptable quality oil. Although closer row spacings of 30 cm increases total plant biomass yield, satisfactory oil yields can be obtained even in wide rows of 60-75 cm apart. The optimum stage of harvesting dillweed for oil is when most of the mature umbels have fully developed seeds that have turned purplish in color. At this time, oil yield appears to be highest and with acceptable quality. At this moisture content, the crop can be cut and distilled immediately without the need for drying in the field.
Oil recovery is lower as the plant material becomes drier.
Screening a number of dill lines have indicated the possibility of increasing oil yields over the current varieties being grown commercially. Caraway - This biennial crop has been grown for its seed and for the essential oil extracted from the seed. It has a wide range of adaptability in the Canadian Prairie and has been commercially grown since the early 70's. However, in recent years the acreage has rapidly expanded and in 1996 estimates ranged from 4000 - 8000 acres in western Canada. Essential oil produced from the seed, besides being used for the flavoring, is also being directed towards industrial purposes.