Pulses are well known for their ability to fix their own nitrogen in-crop, but some farmers choose to add starter nitrogen at seeding. Is it worth it?
While pulses have the ability to fix their own nitrogen, they may need a little help at the start of the year to bridge the gap between seed and about five-node stage, which is when they can begin to fix the nitrogen that they need to continue growing.
The first thing to consider though is a soil test, even when growing pulses, says Mike Palmier of Max Ag Consulting in this episode of RealAgriculture’s Pulse School. If a field has low residual nitrates, it may be a good idea to add nitrogen fertilizer at seeding to support early growth.
When soil testing, the focus should really be on that zero to 6 inch depth in the soil profile, says Palmier. Once the roots outgrow that, in combination with inoculant, they should be able to fix their own nitrogen.
While a lack of fertility at seeding can cause a whole host of problems, high rates of nitrogen early in the season can cause the pulse crop to become “lazy,” negatively affecting the plants’ nodulation. High rates of nitrogen early in the season can also cause a higher risk of molds and disease by increasing plant biomass.
In this video, Palmier explains the levels of nitrates in the soil that pulses require at seeding, how rotation impacts the need for synthetic fertilizer, the importance of a good quality inoculant and the impact that rotation can have on yield loss if there is an inoculant failure.
Subscribe: Apple Podcasts | Spotify | RSS | All Podcasts
