274 Handbook of herbs and spices
among the three cultivars tested, Karzo produced the highest seed yield (1648 kg/ha)
and had the highest essential oil content (3.4%) and for best yields, Karzo required
high sowing rates (about three times the current sowing rate used with other cultivars),
a sowing depth of 2.5–4 cm, and sowing no later than 19 May, to ensure full seed
maturity (Arganosa, et al., 1998). The different sowing dates (between 6 April and 21
June) and seed rates (5, 10 or 15 kg/ha) using C. carvi (cv. Sylvia) were standardized
by Dragland and Aslaksen (1996) for its successful cultivation in various agro-
climatic localities in Norway.
15.2.4 Fertilization
Nutrient intake by caraway plants is intensive and the pure crops require about 10–
15 t/ha farmyard manure and the best fore crops for caraway are considered root and
vegetable plants previously supplied with a full rate of farmyard manure (20–40 t/
ha). Plants ploughed in for green manure could also be recommended. According to
Schroder (1964), 85 kg N, 39 kg P 2 O 5 and 94 kg K 2 O per ha, yields 1.2 and 4.2
tonnes of fruits and straw, respectively. In Poland, caraway crop is usually provided
with 60–80 kg N, 70–80 kg P 2 O 5 , 100–120 kg K 2 O and 20–30 kg MgO, applied both
in the first and second growing season (Ruminska, 1990). Full rates of P, K compounds
together with half amount of N-fertilizers are applied prior to sowing in late autumn
or early spring. The other half of nitrogen is provided after caraway emergence.
However, the main sources of nutrients as mentioned above are mineral fertilizers,
supplied in both years of cultivation in the biennial type.
Annual caraway responds very positively to N and P for increasing plant height,
number of branches, seed weight and seed yield (Munshi et al., 1990) and in Europe
it was found that N is needed mainly during leaf development and K during flower
stalk growth while the P and Ca uptake (as found in plant parts) was high during seed
ripening (Lihan and Jezikova, 1991). The highest seed production has been obtained
when a high level of N is applied before sowing or 50% before sowing and 50% of
the total amount at mid-winter. In Israel, maximum seed yield has been obtained at
50 kg of N/1000 m^2 supplied as ammonium sulphate (Putievsky and Sanderovich,
1985). The highest seed yield and carvone yield were achieved with 30–60 kg N/ha
under the Netherlands growing conditions (Wander, 1997).
15.2.5 Maintenance and care
The important agricultural practices for caraway production after sowing are loosening
of soil, weed control, irrigation and plant protection. It is necessary to decrease the
weed population to the minimum, not only to reduce competition with the crop, but
also to maintain quality at harvest, because many weeds are umbelliferous and their
seeds are difficult to separate from caraway fruits and ultimately reduces its value.
Since the crop growth during the initial period of emergence is slow, crop should be
kept free of weeds during the first two months by practising 2–3 weeding and hoeing
for annual types (Malhotra, 2005). For biennial crops, one weeding and hoeing
would be required in the first year when the crop has started sprouting and another
during spring of the next year after over wintering in April. This practice helps in
removal of weeds and loosening of soil for aeration.
In Russia, herbicides like prometryne and gasgard are used against dicot weeds. In
pure crops of caraway, the use of linuron, prometryne and metobromuron have proved