Orris (_Iris florentina_) is a perennial, native to southern Europe,
and is cultivated chiefly in Italy for its fragrant rootstocks, which
yield the orris of commerce. The plant grows well in a variety of
soils and flourishes in a rich, moist loam, but roots which are grown
in rather dry, gravelly soil appear to be the most fragrant. Orris
is readily propagated by division of the old plants, which may be
set either in the spring or fall about a foot apart in rows spaced
conveniently for cultivation.
Since harvesting usually takes place only once in three years, the use
of the land is required for that length of time in order to obtain one
crop. After the roots are dug they are peeled and dried in the open
air. The desired fragrance does not develop until after the dry roots
have been stored for a number of months, during which time they are
especially liable to the attacks of insects.
The yield is from 5 to 6 tons of dry root per acre. The average annual
importation of orris is normally about 500,000 pounds. The wholesale
prices, which before the war ranged from 6 to 10 cents, in June,
1920, were 14 to 15 cents a pound. The outlook for a profitable orris
industry in this country does not appear promising, and it does not
seem advisable for any considerable number of persons to undertake the
growing of this crop.