Authors: Ignacio Ciampitti, Mary Knapp

The cool weather has delayed Kansas corn planting this year. In 2017, 45% of the corn had been planted by the first week in May. The latest numbers from the USDA National Agricultural Statistic Service (NASS) for 2018 show just 15% planted as of April 22 (Figure 1). The majority of the progress has been in the Southeast Division, where warmer temperatures have prevailed.

Figure 1. Corn planting progress in Kansas as of April 22, 2018. Source: USDA/NASS.

Cold and dry conditions over the last few weeks are presenting challenging soil environments for early corn stand establishment. As a result, corn growth and development progress has been delayed based on the low heat unit accumulation. This has been delaying emergence of the recently planted corn and slowing down growth progress on any emerged crop.

For the next 7-days, now through May 3rd (Figure 2), the outlook for precipitation shows a probability of receiving from 1.15 inches (central section) to less than a quarter of an inch of rain (western part of the state), adding to the limited precipitation already received this past month (Figure 3). Given the dry conditions, this is unlikely to limit field work, but may provide a more favorable soil moisture environment. Warmer-than-normal temperatures will help warm soil temperatures to more favorable ranges. You can monitor changes in soil temperatures at the Kansas Mesonet: http://mesonet.k-state.edu/agriculture/soiltemp

Figure 2. 7-Day outlook precipitation probability for April 26 – May 3. (NOAA)
Figure 3. Seasonal precipitation summary for March 28 – April 26, 2018. (Weather Data Library)

The precipitation outlook for the longer term (6-10 and 8-14 days) is calling for a drier-than-normal start to the period in the western parts of Kansas, with an equal chance of above-or below-normal precipitation for the rest of the state (Figure 4, left map). Only the eastern third has a slight chance of above-normal precipitation in the 8-14 day period (Figure 4, right map).

Figure 4. 6-10 (left map) and 8-14 (right map) day outlook precipitation probability. (NOAA)

Optimal soil conditions have a large impact on corn uniformity and early-growth. Lack of uniformity in emergence can greatly impact corn potential yields.

Producers should go back and check corn planted in early-to-mid April to check stand establishment, number of plants emerged as compared to target seeding rate, and early-growth uniformity. If plants did not emerge, dig and check for any seeds that did not germinate or seedlings that died before emergence.

There is still time to plant corn and get good yield potential. If possible, wait and plant under uniform soil temperature and moisture conditions to guarantee a more uniform early-season plant stand.

Stay tuned for more information about corn planting progress and delayed planted corn in upcoming issues of the Agronomy eUpdate.

Ignacio Ciampitti, Crop Production and Cropping Systems Specialist

Mary Knapp, Weather Data Library