Answer:
Try a product called Liquid Fence, in a spray bottle available at hardware stores. It's about $15. The label says it's designed to repel deer and rabbits, but I find it works for squirrels too. You need to spray it into the holes where you plant the bulbs, on the bulbs themselves in the hole after you drop them in and before you bury them, and then on top of the area once it's filled in. Respray on top every couple days for the first week or so, then once a week.
While not impervious like chicken wire or hardware cloth, it's much more convenient.
PS. this stuff REALLY STINKS (it should also say "human repellent" on the label), but it works.