The document discusses strategies for minimizing the risk of crop failure from diseases like Impatiens Downy Mildew (IDM) through the use of disease resistant varieties, proper cultural practices, and a fungicide rotation program using multiple modes of action applied at key times throughout production. It provides details on susceptibility levels to IDM in different impatiens varieties, as well as integrated control strategies and specific fungicide options and application timings for both young plant and finished plant production.

1. Risk Management:
Understanding and Minimizing Crop Failure
▪ Use ‘High Resistant’ Varieties
▪ Clean production facility
▪ Optimum cultural protocols
▪ “Right chemical-right time”
▪ Monitor and control

2. Impatiens Downy Mildew
(IDM)
Will Healy
Senior Technical & Research Manager
Whealy@Ballhort.com

3. Downy Mildews – Host Specific!
Basil Downy Mildew (BDM)
Peronospora belbahrii
Pansy/Viola Downy Mildew
Peronospora megasperma
Impatiens Downy Mildew (IDM)
Plasmopara obducens

4. What’s the Difference?
Susceptibility, High Resistance, Immunity
Susceptible to IDM:
IE: SE, Xtreme, Lollipop
Immune to IDM: Marigold
High Resistance to IDM: Beacon
SE XP White:
Venhuizen Field Trial Wk 36, 2018 Beacon Orange, White, Bright Red:
Elburn Wk 38, 2019

5. What’s the Difference?
Susceptibility, High Resistance, Immunity
Susceptible to IDM:
IE: SE, Xtreme, Lollipop
Immune to IDM: Marigold
High Resistance to IDM: Beacon
SE XP White:
Venhuizen Field Trial Wk 36, 2018 Beacon Orange, White, Bright Red:
Elburn Wk 38, 2019

6. Right Culture, Environment + Fungicides
= Disease Free Plants
✓Regular Fertilization
✓Dry at Night – No Guttation
✓Reduced RH - <80%
✓Fungicide Rotation

7. Impatiens Downy Mildew Retail Risk Management Strategies
Grower
Assortment
No Control Strategy Integrated Control Strategy
Environment + Fungicide
Option A Vegetative Doubles Vegetative Doubles
Option B
Vegetative Doubles
Susceptible self-sown or plugs
Beacon self-sown or plugs
Vegetative Doubles
Susceptible self-sown or plugs
Beacon self-sown or plugs
Option C Only Beacon self-sown or plugs Only Beacon self-sown or plugs
High Risk
Manage Risk
Reduced Risk

8. Control Strategies
FRAC Code
Use one
43+M3
Adorn + Protect DF
+ Capsil
Not Labeled Drench
43+4
Adorn + Subdue
MAXX
Fluopicolide 4SC
+ Subdue Maxx
Drench
33+4
K-Phite 7LP T/O +
Subdue MAXX
Phostrol +
Subdue MAXX
Drench
Stature SC Forum Spray
Micora Micora Spray
11+7+M3
Pageant + Protect
DF + Capsil
Not Labeled Spray
U15 Segovis Not Labeled Drench
43+4
Adorn + Subdue
MAXX
Fluopicolide 4SC
+ Subdue Maxx
Drench
33+4
K-Phite 7LP T/O +
Subdue MAXX
Phostrol +
Subdue MAXX
Drench
Day After Stick
or Sow
Day 10-14 once
roots are
elongated
US Canada
40
Young Plant Production
Use Different FRAC codes to minimize resistance
Method
Day 24-28 after
Stick or Sow
Plug &
Liner #1
Plug &
Liner #2
(omit with short
crop times)
Day 31-35 after
Stick or Sow
Before ship or
Transplant
Plug &
Liner #3
Treatment
FRAC Code
Use one
43+M3
Adorn + Protect DF
+ Capsil
Not Labeled Drench
43+4
Adorn + Subdue
MAXX
Fluopicolide 4SC
+ Subdue Maxx
Drench
33+4
K-Phite 7LP T/O +
Subdue MAXX
Phostrol +
Subdue MAXX
Drench
Stature SC Forum Spray
Micora Micora Spray
11+7+M3
Pageant + Protect
DF + Capsil
Not Labeled Spray
U15 Segovis Not Labeled Drench
43+4
Adorn + Subdue
MAXX
Fluopicolide 4SC
+ Subdue Maxx
Drench
33+4
K-Phite 7LP T/O +
Subdue MAXX
Phostrol +
Subdue MAXX
Drench
Finish #3
Day 31-35 after
Transplant
Before Ship
Finished Plant Production
Use Different FRAC codes to minimize resistance
Treatment
Days after
Transplant
US Canada Method
Finish #1
Day 7-10 once
roots are at
edge of
container
Finish #2
(omit with short
crop times)
Day 14-28 after
Transplant
40
Always use Fungicides according to label instructions

9. At Risk Crops: Impatiens walleriana
For more resources:
➢Impatiens refresher Impatiens 2.0
➢Fungicide information on control of IDM
➢Creating your own IDM control program.
➢In the Break Room series covers a wide range of topics for growing teams
➢Production resources
➢Tech On Demand Podcasts