“top o the day to you Lassie” – did ye receive a shamrock plants as a bit o a wee gift now me lady. Aye, know the plant well do we now. Oxalis acetosella, or wood sorrel is a plant called shamrock. Oxalis is a perennial plant that grows about 5 inches high. Oh yes its much more common to grow Oxalis outside amongst your Summer Bedding, the annuals, perennials or shrubs. It’s a gardeners plant in many respects.