Q: What’s the impact of soil temperature on crop emergence?
A: Seeding into warm soils ensures the best start for the crop. Proper crop emergence is the fundamental start to reaching the crop’s yield potential.
Seeding into cold soils may result in slower emergence. This places crops at risk of infection by soil pathogens. Pathogens can cause seedling diseases, which can result in poor or staggered emergence or even seedling death.
If seeding into colder soils, one way to lower the risk is to use a seed treatment. A seed treatment will help protect the seed against disease if it has to sit for a longer-than-desired period of time and gives the seed and seedling the best chance of survival. Some seed treatments also provide plant health benefit additives that can help with the pop-up effect of seedlings to encourage faster emergence. Poor emergence may cause lower-than-desired plant stands. Reduced plant stands create an environment more favourable for weed and insect pressure as well as staging issues when timing herbicide and fungicide applications.
Planting at the optimal soil temperatures will help ensure the best crop emergence. Where possible, cereals, peas and lentils should be planted at a minimum soil temperature of 5 C, canola at 7 C and soybeans at 10 C.
If soil temperatures are cooler, seed shallower if adequate moisture is present to access a warmer seedbed. Other considerations include bumping up the seeding rate to compensate for lower seedling survival and use a seed treatment whenever possible. Planting into cooler soils cannot always be avoided but agronomic practices can help to mitigate risk.