Dr. Ajay Nair
Department of Horticulture
Iowa State University

A new publication providing information on micronutrient levels in soil and optimum range in plant tissue is now available at the Iowa State Extension and Outreach store. Although needed in very small amounts, micronutrients have an important role to play in plant growth and development. Most of them are involved in enzymatic reactions that are essential for plant survival such as photosynthesis and respiration. This publication highlights the major roles, deficiencies, and toxicity symptoms of micronutrients in plants and provides an understanding of the interactions between micronutrients in the soil. Click on the link below to download the guide

https://store.extension.iastate.edu/Product/Micronutrient-Publication-for-Vegetable-Growers

2016 Field Day Highlights

Dr. Ajay Nair, Kristine Neu, and John Krzton-Presson
Department of Horticulture
Iowa State University


We would like to offer up a HUGE thank you to everyone who attended and supported the 2016 Fruit and Vegetable Field Day! It was great to have a group of close to 100 people join us for research presentations and hands-on demonstrations.

We would like to especially thank the following individuals and organizations for their support:

• Eric Franzenburg and Iowa Fruit and Vegetable Growers Association
• Liz Kolbe and Practical Farmers of Iowa
• Brian Nordschow and Windridge Implements Inc.
• Donald Lewis, Lina Rodriguez-Salamanca and Laura Jesse with the Plant and Insect Diagnostic Clinic
• Joe Hannan and Patrick O'Malley with Iowa State Extension and Outreach

The day would not have been possible without the tireless efforts of Nick Howell, Brandon Carpenter, and the entire staff of the ISU Horticulture Research Station.

Please keep an eye on our website http://www.extension.iastate.edu/vegetablelab/ for winter workshops and presentations, and know that we already look forward to seeing you for the 2017 Field Day!

Brian Nordshow answering questions about planting and harvesting equipment available from Windridge Implements Inc.

Liz Kolbe sharing the message and work of Practical Farmers of Iowa. She is joined by Lina Rodriguez-Salamanca and Laura Jesse of the ISU Plant and Insect Diagnostic Clinic.

Dr. Ajay Nair and Kristine Neu giving an overview of their colored bell pepper cultivar trial and shading study.

Field day attendees explore the grafted tomato research in a high tunnel. Project supported by IDALS.

Dr. Diana Cochran sharing updates on the apple rootstock trial.

Bryn Takle explains the layout of his hops research focusing on nitrogen fertility.

Kenny McCabe demonstrating the use of the HopsHarvester.

Dr. Ajay Nair and John Krzton-Presson talk about conservation tillage and food safety in muskmelon production.

Hayley Nelson and Dr. Mark Gleason explaining row covers, ProtekNet, and their role in the potential prevention of bacterial wilt.

Students and staff who played a vital role in the success of the 2016 Fruit and Vegetable Field Day.

Dr. Ajay Nair
Department of Horticulture
Iowa State University

A new publication providing information on commercial asparagus production is now available at the Iowa State Extension and Outreach store. The production guide discusses all aspects of production including cultivar selection, fertility management, insect-disease-and weed management, harvesting and storage. Click on the link below to download the guide

https://store.extension.iastate.edu/Product/Commercial-Asparagus-Production

Commercial melon production

Ajay Nair and John Krzton-Presson

Department of Horticulture

Iowa State University

A new publication providing information on commercial melon production is now available at the Iowa State Extension and Outreach store. The production guide discusses all aspects of production including cultivar selection, transplant production, fertility requirement, insect-disease-and weed management, harvesting and storage. Click on the link below to download the guide

https://store.extension.iastate.edu/Product/Commercial-Melon-Production

Wind Damage on High Tunnels

Kristine Neu and Ajay Nair,
Department of Horticulture,
Iowa State University

We've recently received some much needed rain in Central Iowa; however, this has brought along some necessary evils. Wind and the other damaging culprits that accompany summer thunderstorms have been especially unwelcome for producers growing in high tunnels. 

On the evening of July 11 the ISU Horticulture Farm fell victim to the 30+ mph hour winds with gusts upwards of 50 mph. The results were the complete loss of one high tunnel skin and the displacement of a shade cloth on another. Thankfully the research was not compromised. We hope that our local growers did not face the same misfortune!

Ajay Nair

Department of Horticulture

Iowa State University

A new publication providing information on all aspects of Pak Choi production is now available at the Iowa State Extension and Outreach Online Store. The commercial production guide discusses all aspects of pak choi production, starting with with choosing appropriate cultivar, planting method, fertility, etc. Click on the link below to download the guide

http://store.extension.iastate.edu/Product/Commercial-Production-of-Pak-Choi

Managing Stress in High Tunnels: Shade Cloth

Kristine Neu and Ajay Nair,
Department of Horticulture,
Iowa State University

The early onset of high temperatures in June has kept us on our toes as we manage our high tunnel production systems at the ISU Horticulture Research Station. While high tunnels bring many benefits to high value crop production, including season extension and increased produce quality, we find that one major downfall is the increase of heat stress. 

Last year, after blossom abortion due to heat stress and severe sun scald damage on tomatoes within our high tunnel, a 30% light reducing shade cloth was purchased to alleviate some of these issues.When the predicted highs reached over 90 degrees early this month, we knew it was once again time to place the shade cloth on our high tunnel, and there was an audible sigh of relief from the tomatoes.

On June 24 we applied shade cloth to small high tunnels that are being used to trial seven colored bell pepper cultivars. In addition to trialing the cultivars, we are examining the response of the plants and fruit to three different shade treatments- no shade, 30% shade, and 50% shade. Our hope is to hone in on the best production methods for colored bell peppers in high tunnels.

A shade cloth may be a valuable tool to utilize in your high tunnel production system, but we understand that cost is a huge decision factor. Here is a short breakdown of approximate costs taken from a large grower supply company:

• 30% polyethylene knitted shade cloth = $0.20 / square foot
• 1000' spool of polyester curtain cord = $30
• Shade Clip (suggested placement is 2' spacing) = $0.47 / clip

Cost to cover a 30' x 96' structure with a 30% shade cloth = $500 + shipping

Please watch for updates throughout the season regarding our high tunnel production of tomatoes and colored bell peppers.

Unique Insect Feeding Damage on Peppers

Kristine Neu and Ajay Nair,
Department of Horticulture,
Iowa State University

The growing season is never without challenges, and this summer is no exception- especially for our high tunnel bell pepper research! On June 13 we noticed some unique feeding damage on the stems of our pepper plants. This damage was isolated to the stem area beneath the mulch layer.

The stems appear to be completely girdled, but the vascular system of the pepper seems to still be functioning at some level. A week and a half later and many of the damaged plants are beginning to fall over. Some have snapped off completely at the weakened point, but many are still trying to press on and flower. Unfortunately, these plants will likely not be viable much longer either. 

We are working with ISU Professor and Extension Entomologist, Dr. Donald Lewis, to narrow down the source of the damage. Dr. Lewis agrees that this doesn't look like the normal feeding damage for the typical cutworm that plagues vegetable production in Iowa. 

Have you ever seen damage like this in your production system? We would love to hear from you!

Sweet Pea Harvest in Central Iowa

Kristine Neu and Ajay Nair,
Department of Horticulture,
Iowa State University

Yesterday we were invited to check out the harvest of 100 acres of sweet peas on a farm in Central Iowa. The harvest began at 5:00 a.m. and would be completed by early afternoon. The crew included 7 harvesters, 2 transport carts, 2 teams of mechanical support, and a crew of 10 semi trucks on a continuous rotation. The drivers were transporting the peas 180 miles to a processing plant in southern Minnesota; each semi truck load contained approximately 28,000 lbs of shelled peas.

Rye Cultivar Trial - Anthesis and Roller Crimping

Kristine Neu and Ajay Nair,
Department of Horticulture,
Iowa State University


Cereal rye plots at anthesis on May 21, 2016.

Early summer has kept us busy with our cereal rye cultivar trial located at the ISU Horticulture Research Station near Gilbert, IA. This study is comparing five cultivars of cereal rye (Aroostook, Elbon, Prima, Wheeler, and Wrens Abruzzi) for their performance as a cover crop in a roller crimping system. Each cultivar was planted on two dates last fall - September 16 and October 13. 

Pollen being shed at anthesis.

One of our primary questions of interest is, "When does each cultivar reach anthesis?" This question is important because cereal rye cannot be successfully killed with a roller crimper until it has reach flowering stage, also known as anthesis. We saw Aroostook reaching anthesis on May 17 with Elbon and Wrens Abruzzi following two days later. Prima and Wheeler both reached anthesis on May 21.

Cereal rye being terminated with the roller crimper.

   










Due to recent rain our roller crimping was slightly delayed, and all plots were terminated with the roller crimper on Friday, June 3. The plots were evaluated on Tuesday, June 7 to assess the success of the kill with the roller crimper. Aroostook and Wrens Abruzzi appear to have the best rate of kill and would be ready for strip tilling and planting of a vegetable crop. Wheeler and Prima appear to be standing back up, and would require another round of roller crimping to be a viable mulch bed.

Prima (left) and Aroostook (right) on June 7.

For more information on cereal rye and roller crimping, please visit reference our extension publication Strip Tillage in Vegetable Production.
  

Carrot harvest from soil benches

Ajay Nair
Department of Horticulture
Iowa State University

Today (4/21/16) we harvested carrots (cultivar Nelson) and parsnips (cultivar Javelin) from the soil benches. These were planted by students in HORT 471 class (Vegetable Production and Management). Carrots were seeded on 12 January, 2016.

From a 4ft by 4 ft section we harvested between 25-30 lbs of carrots. Parsnips did not do that well and produced smaller roots and yielded around 5-8 lbs from a similar area.

Commercial Potato Production Guide

Ajay Nair

Department of Horticulture
Iowa State University

A new publication providing information on all aspects of potato production is now available at the Iowa State Extension and Outreach Online Store. The Commercial Potato Production Guide, The publication discusses all aspects of potato production, beginning with choosing the correct type of potato to grow, size of seed potatoes, spacing, fertility, and pest management. Click on the link below to download the guide

http://www.extension.iastate.edu/article/commercial-potato-production-discussed-new-publication

Salad greens- Vegetable Production class

Dr. Ajay Nair
Department of Horticulture
Iowa State University

Students in HORT 471 (Vegetable Production and Management) course are growing variety of vegetables in HORT greenhouse. Crops were seeded/transplanted on soil benches with medium consisting of soil, compost, and peat. The course provides students with theoretical knowledge and hands-on experience required for successfully producing vegetable crops. Some of the crops being grown include leafy greens (arugula, tatsoi, lettuce, mizuna, bok choy), summer squash, carrot, pepper, tomato, pole bean, bush bean, sweet corn, cabbage, cauliflower, collards, brussels sprout, and radish. Students had a great time collecting data, harvesting greens, and enjoyed a full-service salad bar yesterday (24 February, 2016). Check out the pictures:

Thrips damage and control strategies

Ajay Nair
Department of Horticulture
Iowa State University

Thrips are very small, slender insects that are common in greenhouses at this time of the year when growers are gearing up to grow transplants. Thrips can cause damage with their feeding, which distorts plant growth, deforms flowers, and causes white-to-silvery patches on leaves (figure below). regular, frequent, and thorough scouting is important to keep a tab on this pest. Use sticky cards and hand lens to trap and properly identify the insect. 





One can use products that have low toxicity such as azadirachtin (Neem-based products, BioNeem), insecticidal soaps (Safer), horticultural Oil, or neem oil (Safe Brand Neem Oil). Biological control is very effective if the infestation is detected early. Biological control includes Predatory mites (Typhlodromips montdorensis, Amblyseius cucumeris, Amblyseius swirskii, Eurseius ovalis) and predatory bugs (Orius laevigatus, Orius majusculus and Orius insidiosus)

Stronger synthetic insecticides such as neonicotinoids, pyrethroids, and organophosphates should be used if the infestation is heavy.