After harvest, farmers have the option of fertilizing fields with potassium and phosphorous in the fall — or waiting until spring.
There are several advantages of applying fertilizers in the fall, said Robert Mullen, director of agronomy at PotashCorp.
Benefits range from resource availability to logistics. There are exceptions to this practice, particularly in coarse, sandy-textured soils. But for many farmers, fall fertilization is advantageous, Mullen said.
He shared his top five reasons to fall fertilize with AgriNews.
1. Logistically more manageable: Farmers have more time, labor and equipment available in the fall.
“Farmers are really in a time crunch in the spring,” Mullen said.
“The primary concern of the farmer is getting the crop planted. If he’s up against a time window and needs to apply potassium and phosphorus, but also needs to get planted, and is facing rain, it becomes a real time-condensed period.”
By applying in the fall, it’s one less thing farmers need to do later.
If you make that investment in the fall, it still will be there by spring, Mullen said.
2. Less soil compaction: In the fall, soil is typically drier, and soil is less susceptible to compaction from heavy equipment. This will provide crops with a better growing environment.
“The reason we typically see less compaction in fall versus spring is primarily related to soil moisture levels,” Mullen said. “Usually they are not as wet — although we do have wet falls.
“Forcing it in spring, where there are higher probability of wetter soils and running floaters over those soils, it can make serious compaction. If I focus on fall, I’ll have less of a problem with soil compaction.”
3. Ideal for deep tillage: Application prior to fall deep tillage allows fertilizer to be more evenly distributed, maximizing crops’ growth and yield potential.
Deep tillage is a practice that varies by geography, Mullen said.
“Deep tillage isn’t the right answer for everyone, but if we can get phosphorous in contact with the soil better, it won’t be as mobile,” he said. “If I incorporate the phosphorous with tillage, the rooting zone will have adequate nutrition by spring.”
4. Less runoff: Fall tends to have lower intensity rainfall events than spring, meaning a decreased chance of fertilizer investments being washed away.
“We in the ag community get our fair share of blame for nutrient enrichment of water bodies, so we’re able to manage our nutrients in a way to immunize risk of offsite transport,” Mullen said.
“We want to keep it in fields and out of the waterways. We’re very well aware of that. Part of strategy is to manage the application to minimize runoff potential.”
5. Product availability: Depending on weather and economic conditions, there may be less intense demand for fertilizer in the fall — making it easier to acquire product.
“This year, because we had such a demand in the spring, the supply chain wasn’t able to get product from the producer to the retailer or to the farmer,” Mullen said.
“We had a wet spring, snowfall, high grain production in Canada and we were competing for railway space. The primary way we move phosphate in to the Midwest is rail through Canada.”
The supply chain struggled to meet demand this spring. But typically, in the fall, there is more product availability, Mullen said.
Erica Quinlan is a Field Editor for AgriNews.
This article originally appeared in AgriNews and has been reposted with permission.