2002 Annual Report
Research
Blueberry Response to Micro-Irrigation Systems
Jerry Wright, Associate Professor,
West Central Research and Outreach Center, Morris, MN
Dave Wildung, Professor, Horticulture, North Central Research and Outreach
Center, Grand Rapids, MN
Becky Sheets, Research Technicians, Central Lakes Ag Center, Staples,
Minn.
Mel Wiens, Research Technicians, Central Lakes Ag Center, Staples, Minn.
Funding Source
U of M Central Regional Sustainable Partnership; MN Fruit & Vegetable
Growers–USDA/MDA Specialty Crops Fund; MDA Integrated Pest Management
Project; Irrigators Association of Minnesota; Minnesota Berry Growers
Association; Agricultural Utilization Research Institute; Minnesota Agricultural
Experiment Station
Objective
- Evaluate effect of micro-irrigation on the growth of half-high blueberry plants.
- Evaluate the impact of an organic production system on micro-irrigated blueberries.
- Provide educational opportunities for area growers.
Project Description
Replicated plots on sandy loam soils are used to evaluate the effect
of micro-irrigation systems (single-line surface); water scheduling scenario
(soil moisture sensors at 40-50 centibars with and without wood chip mulch
and dryland); and organic and conventional production systems on water
use, plant growth, berry yield, and soil pH. St. Cloud cultural blueberries
planted in 1989 are used to assess impacts from these treatments. Single
in-line emitter tubing was used in all of the irrigated treatments. Well
water was treated with an aeration process and a filtering system to study
the effects on emitter plugging. This project will be continued in 2003.
Results
Three organic production treatments, with and without wood chip mulch, and four additional conventional production treatments were monitored and blueberry growth and yield responses were measured. Dry land produces about 60 percent of irrigated yield. Wood chip mulch treatments used 20–40 percent less irrigation water than treatments without wood chips. The wet-high frequency watering treatment operated two to three more times than the moderate moisture strategy treatments. Watermark soil moisture sensors have been used very successfully in scheduling irrigations and most continue to function after 4-5 years of operation. Weed growth was reduced at least 70% when wood mulch was used in the system. Nutrient content in leaves (N, P, K) was reduced slightly in plants grown with wood chip mulch. Over 50 people attended the fourth annual field night at the site.