
False strikes can be a challenge with subterranean (sub) clover, as happened in many parts of the country last year. Rainfall in January caused seeds to germinate, but lack of follow-up rain killed off the seedling. Professor Derrick Moot from Lincoln University says if this happens over successive years, the sub clover seed bank can be decimated and over-sowing or over-drilling may be required to increase the population.
Sub clover needs phosphate to fix nitrogen and for photosynthesis. It grows well at an Olsen-P of 10-18, pHs of 5.6 and sulphur levels of 7-10. Derrick says these fertility levels are typical of many hill country pastures.
Boron and molybdenum are important for clovers, if molybdenum levels are high, farmers can get away with slightly lower pH levels.
Once sub clover has become well established within the farm system, blocks need only be shut-up once every 8 to ten years to allow re-seeding to occur.
Derrick stresses that these forage systems will not develop overnight. There are many farmers throughout the country successfully using this clover to drive lactation and early-season stock performance, but all will have struck management challenges along the way. Derrick says it can take three or four years to refine the system and maximise productivity.
He urges farmers looking to use sub clover as part of a forage and management system to get good advice – and have patience.
Sub clover is another tool in the tool box- but its early season activity makes it a very valuable one.