About the genus

Persicaria is a genus of herbaceous flowering plants in the knotweed family, Polygonaceae. Plants of the genus are known commonly as knotweeds or smartweeds.

In the garden

A North American woodland species in the buckwheat family, Tovara virginiana var. filiformis 'Variegata' is valued where light is limited and a long-flowering late-summer presence is wanted. Flowering takes place from mid summer into early autumn, with widely spaced clusters of small white to greenish-white blooms held away from the foliage on thin stalks. The seedpods are notable for ejecting seeds when disturbed, a behaviour that gives the plant the informal name 'jumpseed'. Plants cope well in shaded or partially shaded sites and are commonly used in woodland borders and beneath deciduous trees where sun is filtered. Cultivated forms vary considerably from wild types, so choose a named selection if you need a specific leaf pattern or habit. The long, wiry flowering stems also add vertical contrast among lower-growing perennials. Expect regular self-seeding where seedheads are left in place; remove or cut back flower stems after seed set if you want to limit volunteers. Conversely, allow a few stems to ripen if you want to collect seed or encourage natural spread — the characteristic jumping seeds are both a curiosity and an effective dispersal mechanism.

From the Fenn Plants journal

• Notes on DaffodilsWhen to plant daffodil bulbs in the UK, how deep, how to naturalise them in grass, why daffodils stop flowering (“blindness”), and why you should never mix cut daffodils with other flowers.
• Keeping Your NerveHow to garden through a heatwave — the best time to water, why deep soaks beat daily sprinkles, caring for pots and vulnerable plants, and why you can let the lawn go brown.
• Made to LastHow to clean, store and protect garden pots and planters — the frost-proof vs frost-resistant difference, winter care for terracotta and ceramic, and how to reuse a broken pot.

More in the Tovara genus

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  Tovara virginianajumpseed
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  Tovara virginiana var. filiformisJumpseed
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  Tovara virginiana var. filiformis 'Painter's Palette'Jumpseed