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to their growing conditions easily. Sorghum species are more adapt-
ed to warmer than cooler climates.
Management and utilisation
The best possible time to seed forage sorghum is preferably once
the spring rains have arrived. The establishment period is thus any
time between October and January all depending on the amount of
rain received.
If the sorghum is to be used for grazing purposes, it is however rec-
ommended that the planting is spread over the planting period, this
way optimum utilisation of the available grazing is achieved. It is sug-
gested that the sowing density be determined by the soil type and
quality and then ultimately the expected rainfall.
It is advised that sorghum is planted in rows under dryland condi-
tions, and row spacing should be widened according to the dryness
of the area. With these seeding conditions in mind, seeding rates
can vary between 5 kg/ha - 20 kg/ha. General recommendations for
annuals are 7 kg/ha - 10 kg/ha in rows, or 15 kg/ha - 20 kg/ha broad-
casted. Perennials are sown at the rate of 12 kg/ha - 15 kg/ha broad-
casted and 5 kg/ha - 7 kg/ha in rows.
Soil fertility is an important factor in the optimal production of sor-
ghums, irrespective of their ability to survive in infertile soils. To
achieve good production it is essential to maintain soil P levels at
15 mg P/kg soil. As a guideline 15 kg N/ha can be applied at plant-
ing, and subsequent top dressings will be determined by the avail-
ability of rain and the level of production required.
Top dressings of 35 kg N/ha can be applied once or twice through-
out the season. If the crop is grazed it is less important to fertilise
with potassium (K), as this element is returned back to the soil via
dung. If the crop is used for silage, significant amounts of K are re-
moved and will need to be returned through fertilisation.
1: Forage sorghum ready to graze.
2: Variable planting dates provide
different stages for grazing to facilitate
optimal grazing throughout the grow-
ing season.
3: Forage sorghum ready for silage
making.
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