Oxalis is a large and diverse group of plants that includes some attractive ornamental varieties. Unfortunately it’s often more familiar to gardeners as a weed, because some species are extremely invasive. Problem oxalis species are either deep rooting with fibrous roots that regrow from any pieces left in the soil, or with roots that form many tiny bulbils that are easy to leave in the ground when weeding, and which will also regrow. Paving cracks, path crevices and greenhouse soil are favourit
