Fertility Management

Improving the quality of organic herb production and marketing

Farmers interested in transitioning some or all of their land into organic production need information regarding the best management practices for these systems. Soil fertility and weed management strategies are imperative for optimum plant growth and yields. Current research in organic herb production at Iowa State University has included investigations into certified organic methods of fertilization and use of organic mulches for weed suppression.

Maintaining nutrient balances in systems utilizing soluble organic fertilizers

The purpose of the present study was to simplify the previous experiments by utilizing the same substrate (peat:perlite), the same additions (low rates of limestone), the same greenhouse, and the same pest management practice (biological control with Encarsia) for all treatments. We also wanted to try several recently-OMRI certified materials which would potentially be easier to formulate, less expensive, and easier to apply with the drip system.

Investigating the Impact of Green Manures and Weed Mat on Soil Biota and Tree Growth in Organic Peach Tree Orchards

In the spring of 2001, organic peach blocks were established at two Western Colorado Research Center sites: Rogers Mesa and Orchard Mesa. These plantings were established to allow multi-disciplinary research, systems comparisons, and demonstration of an organic production system for peaches. The objective of this project is to study the effects of different organic management practices on the soil microbial and faunal communities within peach orchards on the western slope of Colorado.

The Effects of Green Manure, Compost, and Feather Meal on Soil Nitrogen Dynamics, Beneficial Soil Microorganisms, and Bell Pepper Yield

Many organic growers utilize a preceding cover crop or diverse types of organic fertilizer materials for fertility management. Cover crops are one of the most economical sources of organic nitrogen and provide additional potential benefits for succeeding crops. Time or market constraints and the need to intensively farm high value land may limit the use of cover crops and increase the need to utilize organic fertilizer sources of plant nutrients.

Analysis of Compost Tea Under Different Stages of Production

In this paper we review some of the pertinent research concerning organic teas, and note that the results of studies on the effects of such teas, especially as a biocide, is quite mixed. We believe this is due to the variable nature of both the organic feed stock and the methods of extraction. We also make some suggestions concerning a protocol for on-site research into the production and use of organic teas with suggestions for controlling feedstock and extractor variables infield experiments.

Monitoring the ability of compost to provide sufficient nitrogen to a bell pepper crop under drip irrigation

This project was designed to evaluate inputs of various rates of compost on the yield and nitrogen status of a crop of peppers. The grower-cooperator on this project makes his own compost and, for the last two years, he has applied from three to ten tons of compost (along with other nitrogen inputs such as cover crops, feather meal and sodium nitrate) to provide for the nitrogen need of his pepper crops.

Long term vegetable rotation systems using organic production methods and conservation tillage

This experiment is a long term study comparing continuous tomatoes with vegetable rotation under five possible production systems to determine which system is most viable for each vegetable commodity produced. Some vegetables in the southeast can be grown easily with organic production methods (sweet corn, cabbage, broccoli, peppers, etc.) but others have numerous problems (foliar diseases in tomatoes) that will require changes in production strategies. By rotating vegetable crops we are able to see which crops also can be grown under conservation tillage.

Nutrient analysis of organic strawberries: effect of cultivars and mycorrhizal inoculations

Objectives 1. Demonstrate the relative nitrogen performance of standard California cultivars grown under organic management. 2. Determine if a commercial arbuscular mycorrhizae (AM) inoculant could provide mineral nutritional benefit, especially on phosphorus, to the cultivars being tested in the first objective. 3. Provide information that will aid organic strawberry producers in fertility management.

Impact of Disease Suppressive Composts on Organic Vegetable Quality Composition and Yield

The goal of this research was to initiate studies on compost effects on severity of common soil borne diseases and to characterize changes plant growth due to improved nutrient availability and soil microbial activity with compost application in organic production systems. 

Project Objectives

-Analyze several animal manure-based, organic-approved compost products for suppression of important soil-borne pathogens of vegetable crops in the Northeast

-Determine applicability of a farmer-based test kit for assessment of compost maturity to predict suppressiveness

Snap Beans with Enhanced Nitrogen-Use Efficiency for Organic Production-Year 2

Snap beans with enhanced nitrogen-use efficiency
for organic production-Year 2


Subscribe to Fertility Management