I've been battling weeds because I've been afraid to use Preen until I know I won't be planting any irises or daylilies for three months -- which means I can't use it in the late summer/fall when I'm planting -- but am I worried needlessly? I thought the Preen would inhibit the iris roots from growing/developing. Ideally I would use Preen three times a year, but I've not used it in the fall/winter/spring because of worries about plant growth. Please let me know if my fears are unfounded, because I have a bunch of weeds out there right now and would love to use Preen again but felt I couldn't because in Sept. I'll start planting again.
