Date & Time: Sept 7 4:03 AM Eastern
Frequency: weekly
World name: Excalibur
Character name: Deveryn Ev'liarsh
Area and coordinates: Island Sanctuary

Steps:
1. The cropland timer appears to be 48 hours for all crops.
2. I've been regularly harvesting my crops on that schedule: Wednesday, Friday, Sunday
3. I was expecting to harvest Tuesday night around 8:45 PM and I saw nothing
4. 4:00AM Wednesday, my crops are ready, so it seems the timer for the blossom phase reset.