Making the most of nitrogen in tight times

6 March 2015

If finances are tight this year, try to look for effective ways to support profitable production, both now and in the future.

Nitrogen applications are a good example; in terms of return for dollars spent, they have been shown to out-compete supplementary feeds as long as they are used wisely and well.

Nitrogen for boosting established pasture

Nitrogen applications can be profitably used in autumn to extend lactations and build winter feed wedges. Following best practice management guidelines is important at any time to ensure you use the extra feed generated efficiently - and this is even truer when money is tight. Make sure you have a feed budget in place so you can identify the feed deficits you need to fill, then monitor your actual pasture covers and compare them to your targets. This will help you pinpoint when nitrogen needs to go on so that your deficits will be met.

The response you get from applying nitrogen will be affected by a number of factors, but the bottom line is your pasture needs to be growing to respond, and the faster it is growing the bigger the response. So, if it is too dry, cold, or wet, you can expect a poor nitrogen response, and you risk nitrogen leaching as plants will be unable extract nitrogen from the soil. Your soil temperatures need to be over 7°C in autumn – then you can expect to get a response in the range of 4-10kg DM/kg N applied.

Nitrogen use on new pasture

If you have gone to the effort and expense of renewing pasture then you will want to protect your investment by giving it the best start. At sowing, include nitrogen in a starter fertiliser to encourage young plants to establish well and outgrow any competing weeds. After that, the aim is to encourage tillering in ryegrass plants and stolon growth in clovers, and this will require additional nitrogen applications at regular intervals.

It takes around 12 to 18 months before clover plants are established enough to reach their full nitrogen-fixing potential. Until this time you need to make up the difference. Light applications of nitrogen (around 25-30kg N/ha) are best, starting about four to six weeks after sowing and then every six weeks after that (or after each grazing).

Choosing a product

SustaiN is definitely the best product to use in autumn as weather conditions at this time can be highly variable. Recent Ballance research has shown, if you cannot guarantee at least 5-10mm of rain (or irrigation across the whole area) within eight hours of an application, you are better to use SustaiN rather than urea.

The key ingredient in SustaiN slows down the activity of urease, a naturally-occurring soil enzyme that breaks down urea. When this breakdown happens close to the soil surface, it increases the risk of nitrogen being lost to the atmosphere as ammonia. On average, using SustaiN halves these losses, meaning more nitrogen can be assimilated into the soil where it can be used by plants. So, although SustaiN costs a little bit more than urea, it does help to ensure your nitrogen ends up where it can do some good.

For more advice on using nitrogen applications to optimise your pasture production, speak to your local Technical Sales Rep.

Article supplied by Ballance Agri-Nutrients