Nutrient Management Research Database

The objectives of this study were to:
1) Study the impacts of drip irrigation on water use efficiency, fruit quality, storability, and yield of
sweet cherry relative to micro sprinkler irrigation under different ground cover systems.
2) Compare ground cover [straw mulch or fabric (polypropylene) cover] vs. no ground cover, mulch cover vs. fabric cover, and white fabric cover vs. black fabric cover on water use, fruit quality, storability, and yield of sweet cherry, and on plant nutrition and soil fertility as well.
3) Evaluate the long-term impacts of black fabric ground cover on sweet cherry tree nutrition and soil nutrient supply.
4) Estimate the placement effects of organic fertilizers on sweet cherry tree nutrition and
productivity. 

• Drip irrigation significantly increased the percentage of marketable fruit by reducing cherry surface pitting and bruising compared with micro sprinkler irrigation. Straw mulch, black fabric cover, and white fabric cover also increased the percentage of marketable fruit in some years.
• Drip irrigation saved over 70% of irrigation water each season compared with micro sprinkler irrigation averaged over the four ground cover systems.
• Fruit yield under drip irrigation was similar to that under micro sprinkler irrigation. However, there was a trend of yield increase, although statistically insignificant, with straw mulch and fabric covers.
• Fruit quality was generally comparable with drip irrigation relative to micro sprinkler irrigation, and with straw mulch and fabric covers compared with no ground cover.
• Soil available nitrate (NO3 - ) and potassium (K) contents were sometimes significantly lower with black fabric cover relative to no ground cover due to the greater removal of these nutrients by higher fruit yield in 2005-2007. Other nutrients did not differ between the black fabric cover and no cover treatments.
• From a long-term perspective, more fertilizers need to be applied on black fabric ground-covered sweet cherry trees because of the increased tree growth and fruit production.
• Application of organic fertilizers directly on the top of black fabric cover was equally effective as the application of these fertilizers beneath the fabric cover; application of organic fertilizers directly on the top of black fabric cover could save labor.