There are many plants associated with St. Patrick's Day. The most popular is the Shamrock which is a type of clover. Since clover isn't growing yet, a suitable substitute is the Oxalis plant.
Oxalis, a tuberous plant, has the required three leaflet leaves and makes a cute little house plant. They aren't hardy in Vermont but you can grow them as annuals in the garden.
Listen to this episode of The Vermont Garden Journal for growing instructions.
Now for this week's tip: it's time to start your brussels sprout seedlings indoors. Grow seedlings indoors under grow lights for six weeks before moving them into the garden.