Applying fertiliser: The upturn in weather this week has opened the door for more farmers to get fertiliser applied. Many sheep farmers operating on more marginal lands are still not in a position to move with fertiliser but should be ready to take the earliest opportunity, even if this means targeting any drier areas and delaying an application on lands not yet fit to travel on.
For most, straight nitrogen (N) will remain the product of choice for this application. Highly stocked farms that are running behind in their target opening grass cover (650kg to 750kg DM/ha for flocks stocked at 10.5 to 12 ewes/ha) should be applying in the region of 23 to 25 units of N, with some farmers heading into lambing and not likely to get out again for a significant period applying 30 units per acre.
The later application on some farms is also raising the question on whether or not phosphorus (P) or potassium (K) should be applied now. On high P and K index soils straight N will suffice and the advice is to hold off in applying K in high-index soils due to a heightened risk of grass tetany. Soils with a P and K deficit, however, will benefit from receiving a compound fertiliser or slurry application.
At last year’s Teagasc sheep conference, soil nutrient specialist David Wall advised that in the region of 50% of the recommended P and K should be applied in spring once significant grass growth begins which tends in a normal year for sheep farms to be in March or April depending on soil type and farm location. He advised the remainder should be applied in two or three applications in May or June, with maintenance rates of K applied in spring-summer and build-up rates in autumn.
There is a low-to-medium demand for P and K on grazing ground, with livestock recycling a high percentage of these nutrients. The recommended ratio of P to K for grazing ground tends to be one unit P to two units K. The recommended application rates for sheep grazing at 130kg to 170kg org N/ha (10 to 13 ewes/ha) is detailed in the table, with units per acre in brackets.
The rising cost of fertiliser is making the benefit of applying lime even more worthwhile. Lime will generate a return on investment of 6:1 at a cost of €25/t. Soils maintained at the optimum pH and receiving regular lime application as required have been shown to release 80kg N/ha compared with low pH soils while also releasing significant soil P and K nutrients.
Ewe hogget dilemma: Further farmgate price rises are putting a spotlight very much on the dilemma of selling ewe hoggets now or retaining them until breeding sales for those in such a trading system. Typical costs of €30 to €40 per head can be factored into the equation for keeping hoggets until next autumn. The question should then be asked if hoggets are of a quality that will sell at the top of the market next autumn. Types that generally struggle to sell above the lower end of the market will be better off traded in the coming weeks.