To evaluate the protection a patent offers, examine the claims. Bergmoser's claim for her patent (my comments are in regular type, in parentheses) reads:
An article for storing fruit and vegetables comprising a tube of mesh material adapted for permitting passage of gases from fruits and vegetables (and passage of) air and sunlight...(A patent claim typically opens by describing the field of the invention-in this case, storing fruits and vegetables. If the patent claim stopped here, it would be very powerful, as it would apply to all fruit and vegetable storage devices made of mesh. But the patent claim goes on to list additional features, which narrows the patent by restricting the number of potential competitors it protects against.)...having a plurality of elastic constricting means spaced along and affixed to a length of said tube of mesh material? This is what I call an add-on phrase that limits a patent's scope. If someone introduces a product that's similar to Bergmoser's but doesn't have elastic, there's a good chance it won't violate her patent.)...said tube of mesh material having openings extending lengthwise between constricting means whereby pockets are defined in said tubes by said constricting means and said openings. (A convoluted way of saying the patent covers only lengthwise openings. This greatly narrows the patent.)
For Bergmoser, this patent prevents competitors from getting a patent on a similar product, assures she can keep selling her product, and gives her a better chance of licensing her idea if she wants to do so. However, it's not strong enough to stop all competitors for mesh-based fruit-ripening devices. That's where a trademark comes in.