Organic  growers can face tough challenges when it comes to weed control.  But new research published in the journal Weed Science shows weather conditions and well-timed cultural management techniques can make a big difference.

A team from the USDA’s Agricultural Research Service (ARS) analyzed 18 years of weather data to determine the impact of meteorological and management factors on weed abundance at a Maryland project farm.

They found that rainfall during a crop’s early reproductive growth or late vegetative cycle can make the crop much more competitive and able to shade out weeds.  Rotary hoeing, delayed planting and crop rotation were also found to boost crop competitiveness and negatively impact weeds – but to a lesser degree than precipitation.

What should growers do with this information? Though you can’t control the weather, you can respond to it. Remain flexible and adapt the weed management techniques you use to weather conditions and to the shifts you notice in weed populations.

Want to know more? The article “Meteorological and management factors influencing weed abundance during 18 years of organic crop rotations” is available in Vol. 66, Issue 4 of the journal Weed Science.