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

106 articles by this author

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Hydroponic Lettuce Production Workshop The department of Horticulture and Landscape Architecture is hosting a Hydroponic Lettuce Production Workshop on Wednesday, March 29, 2017, 8:30 am to 11:30 am (EST) in room 222, Horticulture Building at Purdue University. Topics include: Most common mistakes made during hydroponic lettuce production (Petrus Langenhoven); Nutrition, temperature and supplemental lighting for hydroponic lettuce production (Krishna Nemali); Market access (Jodee Ellett), and Tour of hydroponic lettuce research at HLA (Krishna Nemali and Petrus Langenhoven). The workshop is free, please RSVP no later than March 20, 2017 by contacting Lori Jolly-Brown (ljollybr@purdue.edu). For More information, please contact Petrus Langenhoven (plangenh@purdue.edu) or Krishna Nemali (knemali@purdue.edu). Michiana Vegetable & Fruit Growers Meeting  Purdue Extension and Michigan State University Extension services are hosting a daylong event that runs from 8:00 am to 4:00 pm on March 21, 2017, at the Elkhart County 4-H Fairgrounds, 17746 County Road 34, Goshen, Indiana. Topics[Read More…]


Figure 1. Take soil samples at 6 inches deep

We can never emphasize too much the importance of conducting soil tests. Ideally, soil test should be conducted on a yearly basis. The reason soil testing is so important is because it provides information about the nutrient composition of the soil so that growers will know how much fertilizer to apply for the following season. In addition, soil tests enables farmers to find out if there are concerns, such as pH, salinity etc. If these factors are off track, we might be able to address the problems before planting. In most cases, addressing the problems before planting is more efficient and cost effective than during the season. Purdue Agronomy Extension provides a list of laboratories that offer soil test services https://ag.purdue.edu/agry/extension/pages/soil_testing.aspx I will use the A&L Great Lakes Lab as an example, explaining how to use this service. A&L Great Lakes laboratories provide seven (S1 to S7) soil test packages.[Read More…]


The transdisciplinary faculty from eight states (Texas, California, North Carolina, Florida, Georgia, Indiana, and Arizona) are preparing a research proposal for submission to the USDA Specialty Crop Research Initiative. The research and outreach activities will be conducted on melons.Your participation either as a producer, a retailer, or a consumer will help to establish a need for this research. We would appreciate your help in participating the survey. The survey is anonymous, it will take approximately 8-10 minutes. The survey should be completed by February 18, 2017. The link to the survey is: https://tamucehd.qualtrics.com//SE/?SID=SV_1YBuufvEu0wmciF


2017 Indiana Small Farm Conference Indiana Small Farm Conference will be held from Thursday, March 2 to Saturday, March 4, 2017 in Danville, Indiana at the Hendricks County Fairgrounds. The Indiana Small Farm Conference is a three day learning and networking event supporting small or diversified farms. Information about this year’s programs, registration and lodging are available at http://www.cvent.com/events/2017-indiana-small-farm-conference/event-summary-24e5817fd2f040679885e788eb478b61.aspx Southwest Indiana Melon & Vegetable Growers Annual Meeting The Southwest Indiana Melon and Vegetable Growers Association (SWIM) will have their annual meeting on Friday, March 10, 2017, 8:30 am to 4:00 pm (EST), at the French Lick Resort & Casino Center, 8670 W. State Rd. 56, French Lick, IN. This year’s program includes Cover crops; Precision water and nutrient management; Commercial sweet potato production; Cucurbit pests; How Dicamba on soybeans affect vegetable growers; Food safety update; Watermelon and Cantaloupe variety update, and a PARP topic Utilizing precision Agriculture. Dr. Ajay Nair[Read More…]


NCR-SARE’s Professional Development Program (PDP) provides funds for professional development projects that provide sustainable agriculture training to agricultural professionals and educators. Projects can be up to three years in duration, and funding level is capped at $75,000 for each project. The 2017 call for proposals is now available online at http://www.northcentralsare.org/Grants/Our-Grant-Programs/Professional-Development-Grant-Program Proposals are due at 4:00 pm CDT on April 5, 2017.


OCCSP provides cost share assistance to producers and handlers of agricultural products who are obtaining or renewing their certification under the National Organic Program (NOP). Certified operations may receive up to 75 percent of their certification costs paid during October 1, 2016, through September 30, 2017, not to exceed $750 per certification scope. Certified organic producers and handlers who have paid certification fees may apply for reimbursement of the incurred cost. Producers and handlers may submit OCCSP applications to Farm Service Agency county offices beginning on March 20, 2017. More information about the program can be found at https://www.fsa.usda.gov/programs-and-services/occsp/ or https://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/FactSheets/2016/organics_fact_sheet_2016.pdf


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There are several potential benefits of growing grafted tomatoes, particularly for early season tomato production in greenhouses or high tunnels. If you are interested in trying this technique but wondering whether it is possible to graft tomato plants by yourself, a Purdue extension publication, Techniques for Tomato Grafting, (https://extension.purdue.edu/extmedia/HO/HO-260-W.pdf ) provides a step-by-step guideline for small growers to explore this technique. A question I am often asked is: when should I start to plant the seeds to produce grafted plants? The chart below shows a general timeline and materials needed for producing grafted tomatoes on a small scale on your farm. As a general rule, the grafting process delays seedling growth for 6-7 days. The delay normally does not make a noticeable difference on the size of seedlings after the grafted plants are grown in a greenhouse for more than 2 weeks prior to transplant. As a matter of fact, grafted[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. Our goal is to provide timely information that will be useful for Indiana vegetable growers. If there is something you’d like to see included, please let us know. Frequently we include links to websites or publications available on-line. If you aren’t able to access these resources, please contact us or a local Extension office to request a hard copy of the information. Since last year, Vegetable Crops Hotline website has a new look. Articles that need your immediate attention are posted under Hot Topics and then will be included in the next issue. If you subscribe to VCH via email, you will receive an email when there is a Hot Topic article posted. All the previous articles published in VCH are available on the website. In addition, the[Read More…]


Figure 1. Seedless watermelon varieties in 2016 variety trial that have unique rind patterns

— Notes from Watermelon Research and Development Group Annual Meeting and 2016 Indiana Watermelon Variety Trial We are proud to be in Vincennes, the heart of watermelon producing counties in Indiana. In case you are unfamiliar with watermelon production here, Indiana is just behind Florida, Texas, Georgia, California and South Carolina in watermelon production nationwide. Indiana has more than 7,000 acres of watermelons valued at over $30 million value. In the recent Watermelon Research and Development Group (WRDG) annual meeting, the group that comprise members from academia, government and industry discussed watermelon varieties. In this article, I will summarize my notes from this year’s meeting and discuss the varieties we tested in Indiana watermelon variety trials in 2016. Mini-watermelons One of the interesting things I learned in the meeting is from a talk by Mr. Greg Hitt from Walmart. He shared data that shows Walmart increased the sale of mini watermelons[Read More…]