Q: Do you know of any plants or flowers that repel squirrels?
A: You didn't explain your motivation for seeking out plants that repel squirrels, but I'd say it's safe to assume you've lost a few to the hungry critters. And I feel your pain.
For many years, I had a pear tree that would put forth literally hundreds of beautiful pears during spring, but by July 4th was stripped bare by squirrels. I would watch helplessly from my window as they climbed a branch, swiped a pear, took a bite and abandoned it for another, like a toddler with a box of chocolates.
It got to the point that when we installed a new deck, I didn't think twice about removing the tree; there was seldom a time when a pear actually remained on its branches long enough to ripen and do me any good, anyway.
Other preferred squirrel foods, which you may have noticed by their disappearances, include other fruits, tomatoes, squash, cucumbers, eggplants, daisies, sunflowers and beans.
If squirrel thievery is a particular problem, odds are best they will leave the following plants alone, in most cases because they find their scents off-putting: fritillaria, galanthus, daffodil, allium, hyacinth, lily-of-the-valley, marigold and often, geranium.