It takes an average of 475 growing degree days (GDD) to teach V6, so anything planted the last two weeks of April should be in this range for all three counties. Be sure to scout your fields and check out our article on whether you need a PSNT : http://extension.udel.edu/weeklycropupdate/?p=11879.

Over the last week, the entire state has experienced about 21 growing degrees per day, so we can easily expect to reach V6 with any fields planted the first week of May if warm temperatures continue. It is possible that saturated conditions have slowed corn development, although there isn’t great information on how this may correlate to GDD. The warmer temperatures that came between rainfalls also could have promoted growth as well as denitrification in saturated soils.

Table 1: Growing degree days accumulated through May 29^th from the beginning of each week.

Jarrod Miller, Extension Agronomist.

If you have had issues with tidal inundation of soils in the past or had some flooding this spring, you may be thinking about remediation methods to get the salt content down. While gypsum is a great method of ameliorating these fields, it works best if your salt issues come from sodium (Na). The calcium (Ca) in gypsum can replace Na on your CEC, which will let rainfall or irrigation leach it below the root zone. Fields where Na contents is greater than 15% of the CEC are the most likely to show toxicity issues and should be taken care of first.

However, if your total salt content is high due to Ca, Mg and Na, gypsum will not solve this issue. In these fields irrigation is your best option with recommendations of up to 6 inches of water to reduce salinity by 50% and up to 24 inches to reduce it by 90%.

Amy Shober, Extension Nutrient Management and Environmental Quality Specialist, ashober@udel.edu; Jarrod O. Miller, Extension Agronomist, jarrod@udel.edu; Phillip Sylvester, Kent County Extension Agent,phillip@udel.edu; Cory Whaley, Sussex County Extension Agent, whaley@udel.edu

Barring any major weather delays, the lion’s share of the corn crop will be planted in the next three to four weeks. Applying starter fertilizer for corn at planting has become standard practice, yet we regularly receive questions regarding the benefits and what nutrients should be included in a starter fertilizer blend. Before we dive into the proverbial weeds, we would like to point out the difference between “pop-up” and “2×2” starter fertilizer setups. Pop-up fertilizers are placed directly in the seed trench with the seed, and because of potential salt-injury, often contain low-salt formulations of fertilizer and are used at low rates. Emergence may be delayed if too much fertilizer is used due to burning of the roots by the fertilizer. More common is the 2×2 setup, which places fertilizer in a band 2” off to the side and 2” below the seed, because it is less likely to injure roots. Therefore, more fertilizer can be used in a 2×2 setup and has greater utility for supplying nutrients to young corn. While pop-up fertilizer setups might be useful, especially for applying pesticides directly in the furrow, the focus of the article will be on 2×2 setups.

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Amy Shober, Extension Nutrient Management and Environmental Quality Specialist, ashober@udel.edu; Jarrod O. Miller, Extension Agronomist, jarrod@udel.edu; Phillip Sylvester, Kent County Extension Agent, phillip@udel.edu; Cory Whaley, Sussex County Extension Agent, whaley@udel.edu; and Richard Taylor, Retired Extension Agronomist.

After what seems to be a never ending winter, temperatures this weekend are projected to reach the high 70s. Thankfully, the extended forecast suggests that those frigid temperatures may be behind us. With the warmer temperatures comes the itch to get your corn planted. Here are some considerations for deciding when to plant corn. Continue reading