Nutrient Management for Peaches. 

 I. Introduction to the Factors Affecting 

 Nutrient iVIanagement 



Karen I. Hauschild 



Department of Plant & Soil Sciences, University of Massachusetts 



Nutrient management is not only related to 

 which elements to apply and when but also to 

 how ground cover, pH, and soil structure affect 

 nutrient availability and to the economics of 

 various management approaches. Proper site 

 management before planting plays an impor- 

 tant role in the success of an orchard block as 

 well. 



Following is a discussion of the major 

 factors that affect nutrient availability in peach 

 orchards. For this discussion the focus will be 

 on mature plantings on a properly prepared 

 site. 



Orchard- floor Management 



Young peach trees are very poor competi- 

 tors for nutrients and for water. The use of 

 living ground covers - native or seeded - can 

 result in poor tree growth, reduced (availability 

 of) soil moisture, reduced leaf N levels, and 

 increased problems with insects, diseases, and 

 nematodes. Results of a study conducted in 

 peach orchards in North Carolina showed that 

 after two growing seasons, peach trees grown in 

 cultivated soil, 25% Bermudagrass, or 50% 

 Bermudagrass had greater trunk diameters 

 than peach trees grown with native weed 

 species, 75% Bermuda grass, or 100% 

 Bermuda grass. Trees in the smaller of the two 

 groupings were up to 67% smaller than those in 

 the larger grouping. 



In the late 1980's, studies conducted in 

 West Virginia suggested that trees grown in 

 undisturbed killed sod (K-31 tall fescue) had 

 greater growth and fruit yield than trees grown 

 in a vegetation-free system. The killed sod 

 slowed the loss of soil organic matter, increased 



water filtration rates, and reduced runoff. 



Crop Removal of Nutrients from the 

 Soil 



According to 1973 figures, peaches use the 

 following pounds of nutrients per acre per year: 

 79 lbs. nitrogen (N), 21 lbs phosphate (PPg), 90 

 lbs potash (Kp), 92 lbs calcium (Ca), and 23 

 lbs. magnesium (Mg). This is not necessarily 

 the amount of each nutrient that should be 

 applied. Efficiency of uptake greatly affects the 

 amount of each element that should be applied 

 (refer to paragraph below). 



Effects ofpH on Nutrient Uptake 



Each nutrient has a pH range at which it is 

 most efficiently taken up by plant roots (Table 

 1). Because soil pH plays a major role in 

 nutrient availability, frequent soil testing is 

 recommended in order to monitor soil pH. The 

 relative level of each nutrient, as reported in a 

 soil test analysis, indicates the amount present 

 in the soil, but not necessarily the amount 

 available to the plant roots. The pH alone and 



Table 1. The effects of pH on the relative 

 efficiency of uptake of nitrogen (N), phos- 

 phorus (P), and potassium (K). 



Fruit Notes, Volume 61 (Number 4), Fall, 1996 



