Sampling season is approaching quickly. As soon as the crop starts going into bins, sampling trucks will be busy taking soil cores. Have you ever wondered about the best timing for soil sampling? There are different opinions on that: fall, winter, or spring – which is the best time to get the most accurate and reliable soil test? Each season has its own pros and cons. In the Canadian Prairies, all three can provide trustworthy results. There are several factors to consider when choosing the best time for your farm:

1. Application Time:

If you apply nitrogen (N) in the fall, fields should be sampled right after the crop is harvested and the soil has cooled to slow down microbial activity, avoiding inaccuracies. If application timing is in the spring, all three seasons may be considered acceptable.

2. Soil Texture:

Soils with a significant amount of clay can hold nitrogen over fall and winter well, making both fall and spring sampling acceptable. Light soils with a tendency to leach should be sampled, preferably in the spring to get the most accurate results.

3. Weather Conditions:

Typically, weather in the Prairies is favourable for keeping mobile nutrients in the soil profile over winter. However, if severe rain events occur frequently, the closer the sampling date is to the application, the more accurate the soil test will be. With climate change, the likelihood of extremely warm winters may increase, potentially shifting the sampling schedule to spring.

4. Logistics:

The larger “window” for fall sampling allows larger producers to effectively manage the sampling process, avoiding delays with sample turnover time or weather events.

Scientifically, soil with average or heavy texture would have very similar lab soil test results compared to those sampled in spring.

If you need to sample your land professionally, contact us for a quote.