- Early preparation and a well fallowed seedbed will give better weed control for summer grasses as these are very difficult to control once the crop is established. Soil preparation similar to cereal and maize is suitable prior to planting.
- Weed free, loose seed beds are essential to obtain the most from forage sorghum; the management is similar to that of a maize silage situation.
Soil test early, increase base fertility to adequate levels if required. pH – between 5.5 and 7.0 (CaCl2)
- Apply starter fertiliser at sowing. For example, 200 kg/ha DAP applied at sowing ensures adequate levels of phosphorous and nitrogen.
Follow each graze or cut with an application of 45 - 60 kgN/ha as a forage sorghum crop will require between 180 - 220 kgN/ha during the growing season.
- At sowing soil temperatures should be 16°C minimum and rising for strong even germination.
- Sow with a drill that can achieve consistent seed depth with excellent seed-to-soil contact.
- Apply pre-emergent herbicide (for grass weeds), and post emergence if required.
- Monitor for pests and treat if necessary.
Grazing / harvest of BMR Revolution
- SF BMR Revolution suits either grazing or cutting.
For hay or silage, SF BMR Revolution can be harvested at 100 cm in height. It will take approximately 40 days to reach height for the next harvest. When cut the crop is 85% water and must be wilted for proper fermentation and conservation of the silage.
Under a grazing regime, SF BMR Revolution can be first grazed at 80 - 100cm which provides the high quality of feed in terms of protein and energy as well as allowing for proper plant development. The crop can be re-grazed or harvested at 4 - 6 weeks intervals.
Forage sorghum bred to contain the BMR gene technology have less lignin and are more digestible giving stock better animal productivity and performance. Excellent for hay production or silage. Low prussic acid levels.
Be aware of nitrogen related animal disorders and manage nitrogen availability accordingly. Rates at sowing and climate will influence this.
Sorghum can contain varying levels of Prussic acids which can be toxic to animals. Factors that will increase the levels of Prussic acids in forage sorghum include severe drought or frost stress, low phosphate availability in soil, and large amounts of nitrogenous fertiliser. Avoid prussic acid problems by using a low prussic acid variety such as SF BMR Revolution, do not graze when crop is stressed, do not introduce hungry stock, and supplement stock with sulphur e.g. lick block.