If you have several seed producing plants in a small area like my seed producing bed shown below...
When the green berries first start filling out good, I place d-CON (mouse/rat bait) inside a homemade bait holder..
In the pic above of my seed producing bed, you can see the black drain pipe in the top left area. I actually have two of those just off to the side of my seed producing bed.
I cut them about 2' long, and staked them down to the ground with a couple metal rods.
When those berries first start filling out good, I put some bait in those bait houses... and that takes care of the mouse, chip munk, type critters.
My seed bed also has a 3' high chicken wire fence around it, which keeps out deer, turkeys, rabbits... or at least it has so far. I started this bed in 2010 and so far not one single top has been browsed by deer.
My berries are usually starting to develop mid July and are turning red late August, thru first week or two in September.
PS... the first fall for my seed bed... I had fully developed green berries, nice and plump, with just a couple turning red (one weekend)... and the next weekend I checked them expecting to start harvesting red berries for planting...
And what I found was EVERY SINGLE BERRY had been eaten in a week. There were piles of berry chips under each plant. Obviously some type of mouse or chipmunk type critter that got them. They started all of a sudden, and had a feeding frenzy.
So when those berries start filling out good... you better do something... I learned my lesson that year.
Good Luck
TNhunter