Timing Florel Spray to Prevent Hickory Nuts

When to Spray Florel on Hickory Trees for Nut Suppression

You sprayed your pignut and shellbark hickories with Florel (ethephon) on May 6th last year, targeting the stage when leaf buds burst and flowers would form, but the treatment didn’t work. The key is not a calendar date but the tree’s developmental stage.

Correct Timing Strategy

Florel must be applied when the flowers (catkins) are just beginning to form as the new leaves emerge. This window shifts each year depending on local weather. If your hickories haven’t yet budded out, spray now. Because rain can wash off the product, reapply after any rainfall. Continue weekly applications for three weeks to ensure you hit the critical period. Since exact timing is tricky, this multi-week approach maximizes your chances of success.

Monitor your trees closely each spring—bud break is your signal to start spraying.