Persicaria chinensis ovalifolia 'Indian Summer' AGM

Indian Bistort Polygonaceae

A particularly handsome Mishmi Hills introduction collected by the late Michael Wickenden, and one of those persicarias that makes you wonder why more of them aren’t grown. Originally circulated simply as Persicaria ‘Indian Summer’ from India, it has subsequently been identified as Persicaria chinensis var. ovalifolia. Growild Nursery notes that the identification was passed on to the RHS, which now uses the varietal name. 

The attraction is the combination of rounded leaves that develop a wonderful purple flush in strong sun and masses of small, globular bright strawberry-red flowers from late summer well into autumn. It is noticeably more rounded and bushy than many persicarias, making an excellent late-season space-filler rather than simply another lanky knotweed. The flowers are particularly good with pollinators, and the plant was featured in the M&G Garden at Chelsea in 2021. 

It prefers a reasonably fertile, moisture-retentive soil, though it is surprisingly adaptable. Full sun produces the best purple foliage colour; partial shade gives greener leaves. The RHS lists it as H4 and awarded it an AGM in 2021. 

• Hardiness: H4, –10 to –5°C
• Height: 60–80 cm
• Spread: 50–80 cm
• Flowers: July–October
• Soil: Moist, fertile, well-drained; clay, loam or sand
• Position: Full sun to partial shade
• Origin: Mishmi Hills, India; collected by Michael Wickende