Contrasting duo of Persicaria amplexicaulis Blackfield and Alba

Revisit the garden with this duo of Persicaria amplexicaulis 'Blackfield' and 'Alba', flowering from summer to autumn in a beautiful contrast of deep purple-red and pure white. These robust perennial plants can reach a height of 1 to 1.2 m (3 to 4 ft) and have elegant green foliage that forms a beautiful backdrop for their flowers. The foliage is not evergreen and disappears in winter, but the plant can withstand temperatures as low as -20°C (-4°F). Prefers well-drained and slightly moist soil.

This duo consists of:

- 1 x 'Blackfield' knotweed: this cultivar stands out with its dark red flowers that catch the eye. The plant forms a clump of about 1.2 m (4 ft) in all directions, ideal for adding depth to a flowerbed.

- 1 x 'Alba' knotweed: this variety shines with its white flowers that add a touch of freshness and brightness. It is slightly smaller than 'Blackfield', reaching a height of about 1 m (3 ft), making it perfect for borders or small spaces.

When planting, it is recommended to place the taller 'Blackfield' knotweed at the back of the flowerbed to maximise its visual impact. The 'Alba' knotweed can be planted in front or to the side. For a beautiful density, plant 3 to 4 plants per m sq and make sure to maintain a distance of 45 to 60 cm (18 to 24in) between each plant.

To create a harmonious garden around this duo of Persicaria amplexicaulis, consider pairing them with plants that share their needs for well-drained soil and semi-shaded to sunny exposure. Asters, especially the variety Aster amellus 'King George', blend in perfectly with their autumn flowering in lavender blue. Helenium, particularly Helenium 'Moerheim Beauty' with their red-brown flowers, offer a captivating colour contrast during the same flowering period. Ornamental grasses like Miscanthus or Pennisetum will also bring texture and movement to the garden. Don't forget about Ferns, which with their delicate foliage create a beautiful backdrop for these perennials.