Trifolium dubium aka Lesser Trefoil

Trifolium dubium, also known as the lesser trefoil, suckling clover, little hop clover, or lesser hop trefoil, is a flowering plant in the pea and clover family Fabaceae. This species is generally accepted as the primary plant to represent the traditional Irish shamrock. It is an annual plant that grows up to 0.5 m (1ft 8in) and is not frost tender. It blooms from May to October, with seeds ripening from July to October. Trifolium dubium is a hermaphrodite (has both male and female organs) and is pollinated by bees. The plant is self-fertile and can fix nitrogen, making it suitable for attracting wildlife. It prefers moist, well-drained soil and can grow in nutritionally poor soil with a pH range from acidic to alkaline. However, it cannot grow in the shade. While Trifolium dubium is native to Europe, it can be found in many parts of the world as an introduced species. It is believed to be an allotetraploid with 2n=32 that arose from the crossing of Trifolium campestre and T. micranthum. Shamrock, a relatively rare houseplant that is easy to grow, is often mistaken for Trifolium dubium. Shamrock needs regular watering to thrive and does best in long-lasting, direct light, less than 1 foot from a window.