A: This is one of those answers I enjoy giving, as the correct answer is to not do anything at all.
White grubs are immature June bugs, and while they usually do the most damage to lawns, they can eat the roots of shrubs and vegetables as well. But you’ve a solid point in your favor – you found a dozen in an eighty-square-foot garden bed. It takes six to twelve of these pests per square foot to do measurable damage, and your plants can outgrow the minor damage this small handful of pests can do quite easily. No treatment is necessary.
Toss the handful of such grubs you find over your shoulder to be an unexpected treat for the birds, and otherwise, don’t do a thing differently. I’m not sure I’ve tilled or worked in a single bed in my entire career in North Texas and not seen a few grubs this time of year.