I take it with a pinch of salt when it happens occasionally but for the 4th time in a row I've logged in I've had weedy gardens both herb and crop. I've resorted to placing a signpost in front of each plot now and listing names so that if I get duplicate visitors I can try to narrow down the offenders.
I've given up on the herb route again too as with the butler situation now it's no fun or relaxation time for me to spend hours clearing up after messy glitchen. I'm fully aware that some aspects of the game don't seem obvious to everyone but could we please get an official post from TS or even a new quest bringing home the suggestion that tending plots you've harvested does bring reward (and also showing that actually doing so is pretty darned civilised and respectful to the player who has put out the gardens to share).
(yes I know I get img for clearing up the mess, but it's IMG I don't need and atm it means I'm throwing currants away each time I replant).