Your Reading List

Foliar Fertilizer

When you’re sitting on the tractor seeding with auto steer you have a lot of time to think. It’s always mind blowing to figure out how much money is going into the crop with every pass. Most Western Canadian farms take the plunge at seeding time and place down a good portion of their variable input costs — seed and fertilizer — then hope for favourable growing conditions to reap the rewards.

Splitting up the application of fertilizer is a common practice in other areas of the world, such as the EU. More recently it’s becoming an option for farmers here. There can be many merits to splitting up your fertilizer application into two timeframes, at seeding and then later in the season, when crop potential can be more easily assessed.

I spoke with Mike Floer who farms near Minton, Sask., about his experience with applying foliar fertilizer. While for many years Floer has split his fertilizer application on his winter wheat acres, this past year he drastically changed his fertilizer practices and placed starter fertilizer down at seeding and top dressed all of his acres. Floer is very happy with the results and plans to continue this into the future.

For 2012, Floer plans to put down a base fertilizer rate based on soil analysis results, including all of his phosphorous, potassium, and sulfer requirements along with a small amount of starter nitrogen. Then he’ll monitor his crops and foliar apply the rest of his remaining nitrogen needs with his high clearance sprayer.

The benefits to this system are multiple.

1. Spreading the risk

Lack of precipitation is the most common limiting factor for crop production near Minton. By placing a portion of the fertility needs at seeding, Floer allows his crop to get off to a good start. When it’s time for foliar application, crop potential is a little easier to estimate. This allows Floer to change application rates, and money spent, according to conditions.

2. Increasing seeding efficiency

One large benefit to foliar application is simply handling less product in the spring. With less time lost filling the drill, seeding can be completed in a much more timely manner.

Floer likes the fact that he can put his nitrogen down when he has time. He estimates that while it took approximately four days to foliar apply the fertilizer later in the season, he saved over a week during seeding. This is definitely appealing for farms dealing with a labour shortage problem.

3. Efficient fertilizer uptake

Splitting up the fertilizer applications means more efficient uptake of fertilizer. Floer estimates he’s obtaining the same results using 80 per cent of the nitrogen due to improved usage.

Last year, Floer produced some of the best crops he’s grown on his farm. He attributes much of that to the split applications of his fertility needs. He’s excited to continue looking at pushing his crop potential, as he believes that he was able to control tillering on his durum with his foliar application, boosting his overall yield and perhaps quality.

Timing tips

Proper timing of foliar application of nitrogen is dependent on the crop grown as well as your main objective. Some farmers look at a foliar application to increase crop yields, others are trying to boost wheat protein levels.

Application tips

Proper application will help ensure beneficial results.

Spray at night, during the early morning, or during a light rain to minimize the effects of leaf burn from the foliar fertilizer.

Look at using nozzles that spray with a direct stream pattern similar to dribble banding rather than those with a triangle pattern, to help minimize leaf burn. This will help to minimize the amount of contact of the urea ammonium nitrate (UAN) with plant foliage and maximize the amount coming into contact with the soil and becoming available to the plant. Yield reductions can occur is excess leaf burning occurs, although the effect on yield is hard to determine. Studies completed at North Dakota State University showed yield reduction only if more than 40 per cent of the leaf surface was burnt.

Be very conscientious about washing out the sprayer afterwards or between uses if the sprayer is going to sit for a couple of days due to the corrosive nature of the UAN.

As with any farm management decision, there are always a few drawbacks. The timing and logistics of applying fertilizer in the summertime can be a bit more cumbersome. If you don’t have on-farm storage, pre-buying or pricing fertilizer can be difficult as you can be buying or taking possession of the UAN when it’s traditionally still elevated in price from spring pricing. Some of this could be offset when you consider the increased crop uptake efficiency and the corresponding reduced rates required.

Improved potential crop yield coupled with the ability to spread out risk and decision making means that foliar fertilizer may have merit for an increasing number of farms. Floer has certainly experienced success with this method, and he doesn’t see himself ever going back to placing all his fertilizer down during seeding. †

About the author

Bobbie Bratrud's recent articles



Stories from our other publications