As August nears, thoughts turn sowing new grass swards to replace older, unproductive swards. Reseeding benefits are well known, such as taking advantage of new variety characteristics, better production on the shoulders of the season, higher stocking densities, bigger yields and higher quality.
However, costs associated with re-seeding are also well known, with new grass ley costing as much as £250/acre, including labour and machinery costs. It is imperative then to give new grass leys the best start possible - maximising the return on investment. Therefore, Farmers should consider these two things when sowing out a new grass sward:
1. Soil conditions. Are there drainage issues that need attention? Is the soil compacted and in need of subsoiling? These two things can make a huge impact on the future productivity of your field.
2. Soil pH. A major player in the availability of critical nutrients to your crop. At a pH of 6.0 – considered quite reasonable by most farmers – nearly 50% of Phosphorus (P) applied to fields is locked into the soil and unavailable to the growing crop. As pH values drop towards 5.5, up to 25% of Nitrogen (N) & Potassium (K) are also locked into the soil and unavailable. P & K in particular are key in the establishment of young seedlings, but even at a pH of 6.0, it is very difficult for the small seedlings and roots to reach the nutrients they need to get off to a good, strong and healthy start.
Liming of the soil to bring pH into the target range of 6.2-6.5 is crucial to the establishment of our grass swards. The historical challenge with conventional lime has been that it is relatively slow to give a full pH correction, taking as much as 6 months before the full lift in pH is realised. By this time, the grass sward has already established and missed the benefits of having the pH neutralised and greater quantities of nutrients available to it at an early stage.
G-Lime granulated calcium lime is a great product to overcome this obstacle. Because the granules of G-Lime are made up of superfine particles of calcium carbonate, G-Lime begins to work immediately to correct soil pH, and the superfine particles break down very quickly giving a full reaction in 4-6 weeks, thus giving your grass sward the best possible start.
Correcting pH with G-Lime is easy, as it can be spread with your own conventional fertiliser spreader, and does not require the same co-ordination with the liming contractor as conventional lime. Soil pH corrections of as much as 0.5 are possible with just 300kg/acre of G-Lime. Further small maintenance dressings, often as little as 50 - 100kg/ac in subsequent years will then help you to maintain your soil pH at your target.
Using G-Lime annually to keep soil pH at target level is key to maintaining the productivity of your grass sward. By keeping pH above 6.2, you then maximise your nutrient use efficiency, resulting in higher yielding and healthier crops. Because the grasses and clovers are then able to extract all of the nutrient they require from the soil, they remain healthier and more productive and don’t die out as quickly, keeping out natural grasses which prefer more acidic soils. As a result, your grass swards will be more productive for longer, extending the period between sowing out new grass swards, and maximising your return on investment.