Square-Stalked St Johns Wort (Hypericum tetrapterum) is, as the name suggests, squae stemed. The stem is hairless with 4 narrow leaves at the base of the plant. Unlike most common St John’s Wort, black dots are rare on the leaves. It produces pale yellow flowers from July to September. These flowers are typically 9 – 10mm wide, with 5 petals on each flower.
As with many of the St John’s Wort family, they all have the distinctive square stem and the definate wings. It is often found in damp ditches and marsh lands.
Height: 30 – 60cm
Flowering Time: July to September
Preferred Conditions: Prefers wet or damp soil and so it will often be found in marshes and on the bank of ponds and rivers.