Agrium (AGU -1.2%) shares have shed ~6.5% since its Q4 earnings report, but Scotiabank says the correction is due to weakness in the fertilizer space rather than Jana Partners' complaints or "uneventful" Q4 results. The firm thinks it's time to buy again, seeing retail metrics are improving and U.S. corn acreage and yields coming in below expectations, which could improve sector sentiment.