The Lawn and Garden Soil Sample program wrapped up for 2015 on November 20. There were 133 soil samples sold through Helena Agronomic Center and the Mercer Soil and Water Conservation District office. 58% of these samples are from gardens, 29% from lawns, 12% from other/unidentified, and 1% from woodland.
Several parameters are measured including: pH, percent organic matter, phosphorus, potassium, magnesium, calcium, and Cation Exchange Capacity. The above graph shows a scatter plot of all the sites in comparison of pounds of phosphorus to percentage of organic matter. While, there is no direct relationship between phosphorus and organic matter, the samples with the highest organic matter (above 8%) do have the highest phosphorus levels in this sample set. This graph also shows the wide range of percentage organic matter of the samples taken. It would be interested to know how each of the gardens and lawns grow in comparison.
The Lawn and Garden Soil Sample Program will continue in early spring of 2016. This program provides an excellent opportunity for continued education and awareness of fertilizer usage on gardens and lawns. If you have a company applying fertilizers, talk to the applicator to understand what is being applied and make sure they are following best management practices during application. Are they sweeping excess dry fertilizer off of sidewalks, driveways, and away from storm drains? Is it a calm day with a potential rain in the near future to help absorb the fertilizer and not blow it away? Are they over-fertilizing? Are you over-fertilizing your lawn or garden? Find out what your soil needs through this program!