The wet weather we’ve had in the Midwest through the spring and early summer has made it difficult to time field operations, letting the weeds get a head start. The last few weeks have been full of hand weeding for me and my summer students. Before we started on weeding, though, we spent a couple of days in the last week of June spreading straw in the potato field. This is part of a weed management trial we have been running for a few years now. We’re comparing the effectiveness of mechanical weeding – tine weeding and hilling – with straw mulch. We’ve seen in the past that the straw mulch does a great job of controlling weeds late in the season as the potato vines start to die back – a time when weeds can turn into small trees seemingly overnight! So, in addition to mulching trial plots in our weed management study, we also mulch our variety trial plots to cut down on weed problems later in the season.

This year we are taking a closer look at some other effects of straw mulch in addition to weed suppression – soil conditions (temperature and moisture), insects (both pests and beneficials), and plant nutrition.

Last week I did our first round of variety evaluations for the 60 varieties in this year’s trial. Although we planted several weeks later than usual due to the wet weather this spring, the plants have grown fast and seem to be making up for lost time. This year my favorite so far is Blue Tom Cat – it has big beautiful vines that seem to be taking leafhoppers and Colorado potato beetles in stride. Many varieties have tarted flowering, a stage that roughly correlates with tuber initiation. The earliest to flower were Barbara, which produces yellow tubers splashed with purple; Hunter, which yields yellow tubers; and Early Bangor, a red potato which has produced well in previous years, comparing favorably with the standard Dark Red Norland.

As you can see, the potatoes are loving the regular rain and mild weather. If you’re growing some of our trial varieties, let us know – how are they doing?

This article was posted in Blog Posts, Research News, Uncategorized and tagged organic potato, organic weed management, straw mulch, variety trials.