Reducing the cost of growing grass
In this article Dr. Peter Lawrence Teagasc drystock advisor Co. Wicklow, has advice for reducing the cost of growing grass. His tips include using paddocks, soil testing and drawing up a fertiliser plan based on the reports and incorporating white clover into grass swards
2022 will be a year of high input prices especially fertiliser, feed and fuel. For livestock farmer’s grazed grass still remains the cheapest feed available on farm despite the increased costs in fertiliser and other farm inputs. Teagasc researchers have estimated that the 2022 costs of grazed grass (per t DM grown) are €64 and €121 including a land charge (€300/ac), respectively. Similar to previous year’s, grazed grass still remains almost 2 times less expensive as silage and 3-4 times less expensive than concentrates feeds. So the challenge for 2022 is can farmers maintain production and maximise animal performance from grazed grass in order to minimise their farm business production costs.
Sub-dividing grazing land into smaller paddocks is essential to be able to carefully manage pastures and protect grass re-growths. Investing in fencing infrastructure to help sub-divide grazing lands into 3-day grazing intervals will have a quick return on investment. There are many ways to divide up fields such as using wooden stakes and high tensile electric steel wire or simply using a more flexible option such as pig tail posts and a reel of poly-wire. By grazing paddocks in 3 days and allowing them to grow in 3 weeks is essential to maximise grass growth and to allow animals graze the grass at its optimum growth stage to boaster animal performance. Increasing animal performance off grass will be essential this year because if animals are below targets weights it will be very expensive to compensate for the lack of performance by feeding additional concentrate feeds. For farmers looking to reduce input costs for 2022, adopting a 3-day paddock grazing system will increase the tonnage of grass grown on the farm without necessarily requiring additional chemical fertiliser to do so.
Most farmers should have a recent soil analysis on their farms. This report should be consulted with an Agricultural advisor to develop a plan to determine:
- Is Lime required?
- What fields should get slurry or farm yard manure?
- What fields should receive compound fertiliser or just nitrogen?
The target pH for grassland is 6.3 so apply lime where required in order to increase the efficiency and response rate from fertilisers. Correcting soil pH will also help to unlock the Phosphorus already in the soils available to plants. Cattle slurry is a very valuable source of organic fertiliser and is currently valued at €50/€1,000 gal). Therefore, cattle slurry should be prioritised to silage ground due to its high Potassium requirements and targeted to grazing land with low soil P & K indexes. Spreading cattle slurry with low emission equipment such as the trailing shoe has the ability to increase the N content in the slurry.
Grazing lands identified with high indexes for P & K (Index 3&4) may be able to skip compound fertiliser for this year. However, there will be a response to spreading compound fertilisers on Index 1&2 soils for P&K.
By devising a fertiliser plan for 2022 based the soil sample reports and crop nutritional requirements there are opportunities for farmers to reduce their total fertiliser spend by targeting specific fertilisers to each field or crop.
Incorporating white clover into grass swards by direct reseeding or over-sowing into existing swards has the potential to reduce the requirement of chemical N to grow grass especially during the summer months. White clover has the ability to fix N from the atmosphere and make it available for plant growth. Teagasc research has shown that swards with 25-30% clover content can potentially supply 100-150 kg N/Ha/year if managed correctly. Consequently, white clover has the potential to reduce the costs of growing grass for grazing and silage production. Clover is very sensitive to soil fertility so it is important that it is only sown into soils with pH of 6.3-6.5 and P&K Indexes are 3&4. The best time to sow clover is from April to June when soil temperatures are above 8oC and when rain is forecasted as moisture is very important for seed germination. Research also shows that grass-clover swards can help increase animal feed intakes and subsequent performance when compared to grass only swards.
Along with Teagasc specialists and researchers, Teagasc advisors also regularly provide articles of interest on Teagasc Daily.