Environmentally Sound Soil Fertility Management

Six best management practices for minimizing the impact of fertilizer on the environment.

You have heard the horror stories about the lingering effects of chemical fertilizers on the environment-water supplies contaminated, air quality compromised, ocean life destroyed. They are alarming and disturbing at the very least. It is easy to believe that the fertilizer industry does not care about what happens to the environment but nothing could be further from the truth. The industry advocates responsible nutrient management that minimizes the negative impacts of fertilizer on the environment.

Recently, four leaders in the fertilizer industry, The Fertilizer Institute (TFI), the International Plant Nutrition Institute (IPNI), the International Fertilizer Industry Association and the Canadian Fertilizer Institute (CFI) collaborated on a new initiative called the 4R nutrient stewardship system. The 4R system involves using the right source of fertilizer, at the right time, in the right place, and at the right rate.

In addition to minimizing environmental impacts, utilizing the 4R practices can increase production, boost profitability and improve sustainability. All best management practices regarding fertilizer use should have the 4R principles at their core.

Here are six best management practices to consider for responsible soil fertility management:

Store chemical fertilizers properly

Limit fertilizers exposure to air, precipitation, groundwater and subsoil by storing them in a dry area that has a base, sidewalls and a roof. Keep fertilizers in a secured area, separate from other chemicals. Store chemicals in their original containers when possible and keep them properly labeled. Containers need to be puncture proof and decay resistant.

Calibrate application equipment accurately and inspect regularly

Inspect application equipment on a regular basis for wear and tear; always keep it in good repair.

Calibrate equipment properly to ensure that fertilizer applications are uniform and accurate.

Use irrigation efficiently

Excessive runoff carries nutrients that can potentially pollute waterways. Consider using drip irrigation or a low energy precision application (LEPA) system to improve irrigation efficiency. Make sure that water applications over crops are uniform and even. Avoid overwatering.

Apply nitrogen fertilizer at the right time

Remember that not all crops are the same when it comes to nitrogen (N). Consider the peak demand times for N applications on a crop-by-crop basis. Applying nitrogen at times when plants cannot utilize it is wasteful, encourages nutrient losses, and can potentially damage crops.

Use mulch where appropriate

The use of organic or synthetic mulch around vegetable crops reduces nutrient losses due to leaching. Organic mulches have the added benefit of providing an additional source of nutrients as they break down, thus reducing the amount of fertilizer needed.

Make use of soil sampling and foliar sampling

Annual soil sampling is a useful tool for establishing a baseline for fertilizer applications. Test results can indicate if pH levels need adjusting, and they are helpful for determining proper application rates. Use foliar sampling results to see if fertilizer applications are working. To be effective, balance test results with crop nutrient needs (based upon practical yield goals).