Wenjing Guan

Vegetable Crops Hotline Editor & Clinical Engagement Assistant Professor
Department of Horticulture and Landscape Architecture
Area(s) of Interest: Commercial Vegetable and Melon Production
Wenjing Guan's website

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New 3-27-2020: H2A Update, Business Resource Guide, Dept. of Labor Info, Farmers Market Coalition Resources. In the rapidly changing present situation we want to share information pertinent to vegetable growers as we become aware of it. Here are resources you may find useful. We organize information in categories such as Financial, Production, Labor, Food Safety, Marketing etc. The newest information will show at the beginning of this article and under specific categories. New for Today (3-27-2020) H2A Update: Waiver of in-person interview requirements for certain H-2A and H-2B visa applicants. https://travel.state.gov/content/travel/en/News/visas-news/important-announcement-on-h2-visas.html Additional info and FAQ at https://www.farmers.gov/manage/h2a COVID-19 Affected Business and Employee Resource Guide from Sen. Braun https://www.braun.senate.gov/sites/default/files/2020-03/Senator%20Mike%20Braun%20COVID-19%20Affected%20Business%20and%20Employee%20Resource%20Guide_0.pdf Information about the Coronavirus Aid, Relief, and Economic Security (CARES Act); the Families First Coronavirus Response Act; and Small Business Economic Injury Disaster Loans (EIDL). U.S. Dept. of Labor – COVID-19 and the American Workplace. Fact sheets, Q&A, and posters for employers and[Read More…]


  March 20, 2020 A Guide for Farmers’ Markets to Navigate the COVID-19 Outbreak WEST LAFAYETTE, Ind. — Farmers’ markets play an essential role in the food distribution network, similar to traditional grocery stores. Consumers depend on farmers’ markets for fresh, local foods, and vendors depend on them as an outlet through which to sell products. Keeping these markets open while maintaining public safety during the COVID-19 pandemic is a priority — evidenced by California’s designation of farmers’ markets as essential spaces amid a statewide shelter-in-place and the continued operation of some New York farmers’ markets. However, markets must implement proper precautions and amend their more social practices. Farmers’ markets have traditionally allowed farmers to socially engage with consumers. At this time, farmers’ markets must shift solely to providing essential spaces for people to purchase fresh, local food. Initiating sensible changes, communicating those clearly to customers and vendors, and considering online[Read More…]


NEWS RELEASE: Special to Agriculture Media and Reporters March 17, 2020 A guide for local producers to navigate the COVID-19 outbreak WEST LAFAYETTE, Ind. — COVID-19’s arrival in Indiana has created unprecedented disruption to local production cycles that bring food, fiber, flowers and more to our restaurants, farmers’ markets and communities. Now is the time to determine the best methods to find and connect with your customers during a time of confusion and challenge. You can play an important role in improving this connectivity along the supply chain and ensuring continued access to fresh produce and products in our local economies, and it is imperative to establish and implement plans before any additional drastic measure occurs that could affect your bottom line. As the indefinite cancellation of the Indy Winter Farmers Market illustrates, the potential postponement or cancellation of farmers’ markets across Indiana could have a major impact on your[Read More…]


We know from published research that the health and quality of a vegetable transplant affects how it will establish, grow, and yield in the field. Our recent work comparing tomato and cucurbit seedling growth in different organic growing media and with and without added fertilizer has provided some good examples of this. See Vegetable Crop Hotline issues 653 and 668 for descriptions of media. Tomatoes flowered and set fruit earlier, and had greater early yield when the seedlings were grown in a media that sustained good growth (Figure 1), or if in a media with low fertility but were provided additional nutrients from solid or liquid fertilizer (Figure 2). What does this mean for transplant producers? Plan to provide nutrients the seedlings need, either pre-mixed in the growing media or by adding fertilizer. Among the media for organic production that we tested, additional fertilizer was most beneficial to those media[Read More…]


Dear Vegetable Crops Hotline readers, Firstly, I want to let you know the status of a few Purdue Extension Events related to fruit and vegetable growers. That PSA Grower Training in LaGrange County that was planned on March 20 was canceled due to concerns about the spread of coronavirus (COVID-19). A Strawberry Workshop that planned to be held in May at Southwest Purdue Agricultural Center may need to be canceled or delayed. We will let you know the decision soon. The Hydroponic Workshop that was planned to be held in June or July at West Lafayette, and the Small Farm Education Field Day that planned to be held on July 30 at Purdue Student Farm, West Lafayette, do not expect changes at this point. We will keep you posted about the details of our coming events. Meanwhile, please read the article below about what you should know and how to[Read More…]


Dear Watermelon Growers, At our past winter technical meeting, several growers suggested fertilizer recommendations need to be reevaluated for watermelon production in our area. This suggestion is timely and critical. We plan to initiate a project for the 2020 watermelon production season to reevaluate the fertility and irrigation practices used in Indiana.  We will identify 7-10 watermelon fields with different irrigation and fertility practices. We will collect soil samples and plant tissue samples at different crop growth stages. Lab results will be shared with growers immediately after they are received. Growers who wish to closely watch the nutritional status of the watermelon plants may want to take this free opportunity. As part of this project, we will collect information about fertilizer and irrigation application, and approximate yield of the evaluating field from growers. Summarized results of this project will be shared at the next Southwest Indiana Vegetable and Melon Growers[Read More…]


Welcome to a new year of the Vegetable Crops Hotline (VCH), Purdue Extension’s newsletter for people in the business of growing vegetables. As usual, we will have fifteen issues throughout the 2020 growing season. The first issue of the year is sent to all who subscribed to VCH via US-mail in 2019 as well as new subscribers for 2020. To continue receiving future copies through US-mail, renew your Hotline subscription using the form attached  to this issue. The year that your subscription is paid through is on the bottom right hand side of your envelope. Note that we provide an up-to three years’ subscription of VCH at a reduced price. If you receive the issue through email, you will continue to receive the newsletters on the issue dates. In addition, you will receive emails if there are articles or announcements that need your immediate attention. These articles will be posted under Hot[Read More…]


A grafted tomato plant grown in a high tunnel

Tomato and Cucumber growers who are interested in grafting tomato and cucumber plants by themselves may find this information helpful. Step-By-Step instruction of how to graft tomato plants is available from Purdue Extension publication Vegetable Grafting: Techniques for Tomato Grafting https://mdc.itap.purdue.edu/item.asp?Item_Number=HO-260-W as well as a Purdue Extension video https://www.youtube.com/watch?v=7Ufx66Isf88 A cucumber grafting instruction was also released. It provides step-by-step guidance of cucumber splice grafting technique. The publication is available at https://www.extension.purdue.edu/extmedia/HO/HO-328-W.PDF The cucumber grafting video is available at https://www.youtube.com/watch?v=z-tXoobiMnY&t=1s


Table 1. Growing media evaluated and major ingredients as listed by manufacturer.

Growing media for organic transplant production vary a lot in their chemical composition: pH, electrical conductivity, nutrient levels, and C:N ratio. This of course influences how seedlings grow. Knowing the characteristics of growing media can help growers decide whether adding nutrients or materials to adjust pH are likely to improve seedling growth. As part of our research into media for organic transplant production we would like to test growing media used by Indiana growers using organic practices. The media could be a commercially available product, or a product made on the farm. If you would like your media to be tested, please fill out the form at https://purdue.ca1.qualtrics.com/jfe/form/SV_eezVW7ubRhgh3Ip . Wait for notice that your submission will be accepted and then send 4 pints of media to Liz Maynard, Purdue University, 1101 Glendale Blvd, Suite 101-A, Valparaiso, IN 46383. To request a hard copy of the form, contact Liz Maynard, emaynard@purdue.edu, [Read More…]


It is time to renew your Indiana Vegetable Growers Association (IVGA) membership for 2020. Please use the form attached to this newsletter or download from ivga.org/renewal.pdf and send in with your membership dues. About IVGA IVGA was established in the early 1900’s to be the Voice for Vegetable Growers in Indiana and is dedicated to the improvement of vegetable production and marketing in Indiana. The IVGA supports education and research about vegetables and melons in Indiana, and as your advocate, the IVGA is your resource to help find solutions for your everyday problems. Join today and be a part of a great team in Indiana!