In addition to extracting your pure lavender oil, you can also extract Oil of Spike from the left over stems, which was used as a Lavender Painting Medium and has many other uses.
Oil of Spike Lavender is the ultimate less-toxic painting medium! It is listed by the FDA as (GRAS) "Generally Recognized as Safe".
Oil of Spike Lavender is the medium used by Great Masters and recent Artists , including Leonardo and Netherlands painters. Pacheco, in his Arte de la Pintura published at Seville in 1649, advised artists to moisten just the tip of the brush in lavender oil. Oil of Spike Lavender was often washed over a new canvas to prepare it for painting. It was also mixed with the pigments as a base. An artist would dip the brush hairs in the Spike Oil to make brush strokes smoother. Oil of Spike Lavender was the medium of choice from the fourteenth century on. It has an appealing uplifting scent / aroma, and only a small amount is needed - a drop or two at a time.