For the past few years, ginseng crop updates have been issued weekly for the first half of the summer and biweekly for the remainder of the growing season. With the change to a blog format, the ginseng updates will now be issued on an irregular basis throughout the growing season as issues occur. Growers requesting specific topics of interest can leave a comment on the blog. Blog posts will focus less on reminding growers of routine production practices and more on non-routine issues and new resources and information.
With the mild weather over the past week and forecast for the next week, ginseng will be rapidly emerging through the straw. However, emergence is about 3 to 4 weeks later than last year and closer to normal for this date. Application of products for disease and weed control should be adjusted accordingly.
Here is a preview of what to expect this coming growing season:
With the wet conditions in April, root diseases would have had a chance to spread. However, temperatures were cool and disease progress would have been slow. Any mild and wet period that occurs over the next few weeks could result in foliar Phytophthora outbreaks. Gardens should be constantly monitored during and after wet conditions for any symptoms of Phytophthora. Figure 1 shows the most characteristic symptoms of the disease at this time of year. Rhizoctonia issues have been on the increase in the past two years, possibly due to mild winters. Growers now have a few options to suppress Rhizoctonia beyond the seedling year with the recent registrations of Scholar and Allegro.
Figure 1. Typical symptoms of foliar Phytophthora on ginseng.
The last two summers have been challenging for seed production. Dry conditions led to berry abortion and potentially under-developed seeds. Seeds should be tested for viability before planting and seeding rates adjusted to ensure a good stand.
The Ginseng Scout Training Workshop (formerly the Ginseng Garden Walker Workshop) will be held May 16 from 9:00 to 11:00 pm in the Simcoe Station boardroom. To register please call the Agricultural Information Contact Centre at 1-877-424-1300.
A ginseng sprayer workshop will be held Wednesday, June 19 at a grower site. The workshop will demonstrate sprayer best practices and compare nozzle types. Dr. Jason Deveau, OMAF and MRA’s Application Technology Specialist will lead the workshop and will be able to answer your questions. Details about the workshop will be posted to the blog over the next two weeks.
A fumigation workshop will be held this coming fall or winter for any ginseng, tobacco, strawberry or other crop producers who fumigate. It will discuss fumigation best practices, updates on fumigant mitigation measures, and research trial results. Details will be posted closer to the date of the workshop.
The Ontario Ginseng Growers Association in collaboration with several OMAF and MRA staff and ginseng growers have received funding from the Canadian Agricultural Adaptation Program (CAAP) to set up two fumigation trials on grower sites. The one site will be on new land and the other will be on a replant site. The goal will be to compare tarped vs untarped fumigants and a few alternative products and to determine if they can be used to reduce the effects of replant disease. Trials will also be conducted on strawberries to test some in-season treatments for control of root lesion and root knot nematodes.
The original fumigation trial established in 2010 is now entering its third year. At the end of the summer, the trial will be assessed for total yield and final disease severity. This final assessment will provide answers to two main questions: 1. Will the plants have grown out of the extensive nematode damage that was found in the seedling year? 2. What effect will the fumigants have had on other soil-borne diseases that were not found in the seedling year? Results of this assessment will be provided at a fumigant workshop held in the fall or winter, at the OGGA AGM in the winter, and on the blog.
A Ginseng Replant Disease Committee has been established consisting of OMAF and MRA staff, growers, industry representatives, and researchers. This committee will guide replant research over the next few years and help OGGA secure funding for research projects. A project will be initiated this year by AAFC researchers in London to begin solving this important issue for growers.