Guide to Urban Gardening in Winooski Valley, Vermont

Urban Farm DB summary

This guide established a baseline of soil health for community gardens in the Burlington, Vermont, area of the United States. Ten sites in the Winooski Valley area were soil-sampled in fall 2018, and eight sites in the Chittenden County vicinity were sampled in spring 2019 for comparison, using the Modified Morgan's Universal Extraction Solution to quantify phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), pH, and percentage of organic matter, along with testing hypotheses about nutrient concentration changes from 2011 to 2018 under till and no-till management. Nearly all soils sampled in the Winooski Valley area were found excessive in phosphorus, potassium, and magnesium, most likely due to soil amendment application. Comparing the 2018 tests with tests done by Burlington Parks, Recreation, and Waterfront in 2011, only potassium had increased significantly, and tillage (till vs. no-till) did not affect nutrient concentrations. The guide notes concern that these excess soil nutrients could be exported from the gardens via erosion and leaching, given the gardens' proximity to the Winooski River and Lake Champlain.