Davana is a delicate, erect, branched annual herb with a flowering top that yields an essential oil, extensively used in high grade fine perfumes. The oil is also used for flavouring cakes, pastries, tobacco, beverages, sausages and preserved products. The leaves form an important component of garlands and bouquets. Its origin can be traced back to South India. Karnataka, Tamil Nadu, Uttar Pradesh and Andhra Pradesh are some of the major producers of Davana.
The plant Davana Artemisia pallens Wall.ex DC., belongs to the family Compositae (Asteraceae). It is an erect branched annual herb 45-60 cms tall and covered with greyish white tomentum. Leaves alternate, exstipulate, petiolate, lobed; inflorescence capitulum, axillary, peduncled to sessile, heterogeneous with yellow glabrous florets; involucre two or more, seriate, ovate to elliptic-linear; inner florets 5-lobed, bisexual; stamens 5 with free epipetalous filaments; style bifid.
Davana is a delicate plant and hence cannot withstand heavy rains. Light drizzles, bright sunshine, and a mild winter with no frost and heavy morning dew is ideal for Davana cultivation, especially during the growing stage. Cloudy weather and rains during flowering and seed ripening stages are known to adversely affect the yield. Usually the crop grown during November gives the maximum herb and oil yield. The crop is often grown round the year for use in garlands and bouquets. The plant grows on various types of soils ranging from sandy loam to medium black soils, but humus rich red loam soil is most suitable. The plant is propagated by seeds. Seeds are short-viable and cannot be stored for long. Transplanting is generally practiced for this crop. Typically, a nursery area of 500 m2 sown with about 1.5 kg seeds is sufficient for planting one hectare. Seeds are usually mixed with fine sand, broadcast over the nursery bed, covered with a thin layer of sand and watered regularly. Germination occurs in about 3-4 days. When the seedlings are 10-12 cms tall, they are transplanted to the main field at 15 x 7.5 cms spacing.
Post Harvest Technology
The crop is harvested during February-March when the flowers start blossoming. Flower to plant ratio at the time of harvest is reported to be important for Davana cultivation. Harvesting is done by cutting the whole plant with sickle at a height of 10 cms from the ground. The herb yield is about 8-10 tons/ha.
The harvested herb is dried under shade for 2-3 days. The dried herb is then steam distilled for a period of 6-8 hours to extract essential oil. The flower heads contain 0.3-0.4% of oil and in general, an oil recovery of 0.2% is achieved from the whole plant. The oil yield is 12-15 kg/ha.