This is the first crop update of the 2026 growing season.
Table of Contents
Emergence and Growing Degree Days
Accumulated Growing Degree Days (Base 5°C) at Delhi up to April 12 are 5 days ahead of the 25-year average, which suggests crop emergence will be ahead of normal. We have accumulated 68 GDD up to this point which was reached on April 18 in 2025, April 9 in 2024, April 14 in 2023, and April 23 in 2022. This is based on air temperatures alone, which doesn’t tell the whole story. This was the first winter in many years with significant frost in the ground. Soil temperatures are more important than air temperatures for determining emergence dates for ginseng, and these may be lagging behind air temperatures a bit compared to previous years. This is because some of the warm air earlier in the spring would have been needed to melt the frozen soil without contributing to ginseng growth. However, if the forecast for very warm day and night temperatures this week is accurate, by the end of Saturday, April 18, GDD may be at the same stage it is normally at on May 2, a full two weeks ahead of normal. After that time, GDD accumulation may slow for a few days as temperatures drop below normal again. Given all of this, expect ginseng to emerge ahead of normal, unless there is a prolonged period of below normal temperatures ahead of emergence.
This time of year, there is still the risk of snowfall, although the risk goes down considerably every week. April is also a high-risk time for high winds. As a result, it is best to wait as long as possible to pull the shade over the gardens, although labour availability often forces some growers to pull shade early. Ginseng plants do not need shade protection until the earliest tops are emerging out of the straw, and the leaves begin to turn upwards, which is likely still a couple weeks away for older gardens, even if emergence is ahead of normal so far.
Herbicides
Given the potential for earlier than normal emergence, the existing wet soils, and the forecast for rain on and off this week, it is likely getting too late to apply glyphosate for weed control. There is a risk of the product soaking into the straw and remaining active and then damaging the ginseng tops as they emerge. To avoid damage, glyphosate should be applied before tops begin hooking out of the soil under the straw, and also applied under dry conditions to dry straw so it can be deactivated before emergence.
Pests
The longer and colder winter with consistent snow cover means there are no red-flags of pests that may be more of a problem heading into the spring. Forecasted rains along with wet soils may increase the risk of Phytophthora as temperatures warm. Based on last year, ginseng leaf folders will begin to emerge as the tops in older gardens begin to emerge through the straw. Scouting programs should be in place by that time to determine if insecticide sprays are warranted.
Pest Control Product Updates
There have been only a few product changes for ginseng over the past year:
- Kenja 400SC is now registered for control of cylindrocarpon (ilyonectria) root rot on ginseng.
- Vayantis seed treatment is now registered for control of Pythium on ginseng. This registration does not include other formulations of Vayantis.
- The label for Quadris Flowable has been changed from 2 applications per crop (1 at seeding and 1 at seedling emergence) and a 720 day Pre-Harvest Interval (PHI) to 1 application per year at emergence and a 90 day PHI.
- Admire Flowable is no longer permitted for control of grubs in ginseng. There are now no products registered for grub control in ginseng.
