Note: Not all indicated timings may be necessary for disease control.
| Disease | Late Budbreak/Pre-bloom | Popcorn | Full bloom | Petal fall | 2–3 weeks later | Preharvest 1–10 days1 |
|---|---|---|---|---|---|---|
| Botrytis | 0 | 3 | 3 | 2 | 0 | 3 |
| Brown rot2 | 0 | 3 | 3 | 2 | 0 | 3 |
| Jacket rot/Green fruit rot | 0 | 0 | 3 | 2 | 0 | 0 |
| Powdery mildew | 23 | 2 | 3 | 3 | 3 | 1 |
| Rating: 3 = most effective, 2 = moderately effective, 1 = least effective, and 0 = ineffective |
| 1 Select broad-spectrum fungicides (or combinations) that have activity against both brown rot and Botrytis fruit rots. |
| 2 Begin at popcorn and repeat every 10 to 14 days through bloom if rains continue. |
| 3 Use sulfur at late bud break and other fungicides for later treatment. Treat immediately if mildew is found on shoots or leaves on inner scaffolds. |
Acknowledgment: Adaskaveg et al., 2022. Fungicides, Bactericides, Biocontrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California. (PDF)