b'ROUNDTABLE The Perks of Cover CropsHow can cover crops help your soil and potato yieldsBY: ASHLEY ROBINSONJUDITH NYIRANEZA Editors note: This interview has been edited for length and clarity.research scientist in nutrient management and soil health withSpud Smart (SS): Why grow a cover AAFC Living Lab crop?AtlanticScott Gillespie (SG): The first set of reasons is to hold the soil in place and SCOTT GILLESPIE to hold on to the nutrients. To me, this is something that will always pay. Losing regenerative ag consultant with Plantssoil costs you money. You may be able Dig Soil Consulting Ltd.to compensate for it by adding more fertilizer, but you lose much more than that if you regularly have water flowing through the profile, you can lose the mobile nutrients such as nitrogen. The next set of reasons to grow a cover crop is to increase water infiltration, increase nutrient availability and to lower pest pressures. Water infiltration may be increased within weeks of a cover crop being established, but its more likelyA cover crop of forage pearl millet. something that will gain over multiplePHOTO: AGRICULTURE AND AGRI-FOOD CANADAcycles. Water infiltration is not the total amount the soil can hold. This refers toused an organic approved product. The how fast the water can move into the soil.first application will usually give the When you have good water infiltration,greatest return. Think about the week you can take in rainstorms quickly andbefore canopy closure. Early blight may have less runoff. or may not be appearing. But as soon The final reason of better reasonsas the canopy closes it has the ideal to grow cover crops is to lower pestenvironment, the humidity will be higher, pressure. Herbicide tolerant weeds are aand the spores will be coming from the common reason that most farmers in thesoil. Good coverage slows or stops this United States got into cover crops, and itinitial infection and makes the whole rest is where they have the most success. Byof the season easier. covering the land with the best species forIf you only sprayed once, this is the one the job, they crowd out the undesirablethat would give you the most money back. species. Its not 100 per cent control, but itThroughout the season the subsequent may allow them to use the herbicides thatsprays should continue to give you more ROUNDTABLE SUPPORTED BY: they do have more effectively. money back than spent on the product and the application costs. Scouting spore SS: How can cover crops helptraps, weather, irrigation and many other reduce expenses on the farm? factors will help will play into how many SG: I want you to think about somethingsprays, what products and how often that all potato growers usefungicides.theyre used. The best time to stop is just Even if youre organic, Im sure youvebefore the cost is greater than the return. 44SPUDSMART.COM Fall 2021'