Vegetables

Vegetable Production

Croptime: Croptime introduces degree-day (DD) models for vegetable varieties and weeds. Vegetable DD models can help schedule planting dates and predict harvest dates more accurately than calendar days. Weed DD models can predict development of first germinable seed, and help reduce the risk of weed seed rain. 

Kabocha and Buttercup Squash for Western Oregon Gardens: Kabocha and buttercup squash are gaining popularity for their outstanding culinary characteristics and small size. The squashes' intriguing history, production practices, flavor and uses may inspire more gardeners to grow and eat this exceptional vegetable.

Pacific Northwest Watermelon Production East of the Cascades: Here are steps to successful commercial watermelon production in the Columbia Basin and other warm-climate regions of the Pacific Northwest. You’ll learn best practices for cultivar selection, site preparation, planting, pollination, irrigation, pest management (weed, insect and disease), harvest, and marketing.

Nutrient Management & Soil Health

Nutrient Management for Sustainable Vegetable Cropping Systems in Western Oregon: This publication reflects over 30 years of vegetable production research conducted in the Willamette Valley. It is divided into three main sections: sustainable soil health; soil testing and nutrient management; and nitrogen management. The appendix includes detailed information on the technical aspects of fertilizer technology.

Nutrient and Soil Health Management for Sweet Corn (Western Oregon): This guide integrates recommendations for nutrient management with cover cropping practices that promote soil health. Recommendations for nutrient rate, source, timing and placement for nitrogen, phosphorus, potassium, sulfur, calcium, magnesium and zinc are provided for organic and conventional cropping systems. Cover cropping practices that reduce soil erosion and conserve nutrients are highlighted.

OSU Organic Fertilizer & Cover Crop Calculator: Predicting Plant-available Nitrogen: This online tool predicts plant-available nitrogen released from organic fertilizers and cover crops, compares the cost of different inputs and supports nutrient management planning.

Estimating Plant-Available Nitrogen Release from Cover Crops: This publication explains how to sample cover crops and estimate the nitrogen fertilizer value of winter cover crops using the OSU Organic Fertilizer and Cover Crop Calculator. It describes some research conducted in the Willamette Valley, and includes some Willamette Valley case studies.

Soil Nitrate Testing for Willamette Valley Vegetable Production: A soil nitrate test measures the concentration of nitrate in the soil at a specific moment in time, including nitrate originating from organic inputs, fertilizer, and soil organic matter. This publication describes how to use in-season soil nitrate testing to adjust side-dress N fertilizer application rates to match crop requirements.

Nitrogen Uptake and Utilization by Pacific Northwest Crops: This publication provides information on the timing and pattern of biomass accumulation and nitrogen (N) uptake for a variety of Pacific Northwest crops. You can use this information to schedule N fertilizer applications for maximum efficiency. To achieve near-maximum crop yields, an adequate supply of available N must be present during the period of rapid N uptake by the crop. Supplying N when it's most needed usually reduces the amount of N lost via nitrate leaching, denitrification, and other processes. Improving the timing of N applications can provide three benefits: It can improve crop yield and quality, it can reduce fertilizer costs, and it can help protect the environment.

Soil Fertility in Organic Systems: A Guide for Gardeners and Small Acreage Farmers: This publication discusses the many types of fertilizers and soil amendments available for organic crop production. Fertilizer formulations, nutrient availability, and application practices for common organic products are also explained. 

Estimating Nitrogen Mineralization in Organic Potato Production: Describes a "crop N uptake" method for estimating N mineralization from soil organic matter. Crop N uptake is a site-specific indicator of N that is "available" to the crop.

Fine Tuning Nitrogen Supply in Organic Vegetable Cropping Systems: This short video from the 2020 Soil Science Society of America Conference describes recent research into nitrogen management in organic vegetable cropping systems.

Biodiversity & Pest Management

Organic Management of Flea Beetles: Flea beetles are common garden pests found throughout the Pacific Northwest. Flea beetle feeding on plants in the Brassicaceae and Solanaceae families can scar foliage and potato tubers, leading to reduced marketable yields and potential total crop loss. This publication introduces current organic management options, including cultural control techniques such as trap crops, companion plants, and mulches; biological control; and approved organic pesticides.

Wireworm: Biology and Nonchemical Management in Potatoes in the Pacific Northwest: Wireworms can damage roots of a wide range of crops. This publication explains the wireworm life cycle and describes a program for monitoring and risk assessment in potatoes. Management methods that are discussed include crop rotation, soil drying, flooding, cultivation, resistant varieties, soil amendments, early harvest, trap crops, and biological control. 

Integrated Clubroot Control Strategies of Brassicas: Nonchemical Control Strategies: Clubroot (Plasmodiophora brassicae) is a major soilborne disease of brassica crops in the Willamette Valley. This publication provides information on integrated control strategies to minimize crop loss.

What's Wrong with my Potato Tubers? Diagnosing Tuber Abnormalities in Western Oregon and Washington: Describes and illustrates (color photos) tuber damage caused by insect pests, plant diseases, and physiological disorders.

Weed Management

Weed Management in Conventional and Organic Snap Beans in Western Oregon: Discusses weed prevention and management in conventional and organic snap bean production.