Species knotweed
Light pink flowers with white stigma and style, yellow anthers, white filaments and dark-green stems.

knotweed

Persicaria affinis 'Superba'

Knotweed (Persicaria affinis 'Superba') is an attractive low-maintenance perennial with deep burgundy-colored foliage. With a neat, mounded shape, it is ideal for flower beds and borders. Its spikes of rosy pink blooms appear in mid-summer and add a nice touch of color to landscapes. The foliage remains evergreen in warmer climates, making it an eye-catching choice for year-round gardening. Its fast growth rates create dense thickets of upright stems, effectively crowding out weeds and other invasive species. To maintain an attractive appearance, prune it back in early spring and fertilize twice a year.

Cycle:

Herbaceous Perennial

Watering:

Average

Propagation:

Division,Cutting,Layering Propagation,Seed Propagation,Grafting Propagation

Hardiness Zone:

5 - 8

Flowers:

Pink Flowers

Sun:

Full sun

Leaf:

Yes

Growth Rate:

Low

Maintenance:

Low

Drought Tolerant:

Yes

Salt Tolerant:

Yes

Invasive:

Yes

Care Level:

Medium

watering

Knotweed (Persicaria affinis 'Superba') thrives in moist, well-drained soil and benefits from regular watering. During the growing season when the weather is warm and dry, water the knotweed's soil thoroughly once or twice a week to keep it moist. Always check to ensure that the soil is not overly saturated before watering. This plant prefers its soil to be kept evenly moist. When the weather is cooler or during the dormancy period, reduce watering to once a week.

sunlight

Knotweed (Persicaria affinis 'Superba') plants prefer plenty of sunlight and should be grown in an area that gets at least 6 hours of direct sun per day. In areas with hot summers, some afternoon shade should be provided to prevent leaf burn. In cooler climates, partial shade may be beneficial to protect the plant from scorching sunlight on hot summer days. Knotweed should not be grown in full shade, as this can lead to poor flowering and sparse foliage.

pruning

For knotweed (Persicaria affinis 'Superba'), pruning should be done in early spring after the plant has gone through a period of dormancy and begins to grow again. Prune away any dead or damaged stems and remove any diseased foliage before new growth begins. It is important to ensure that the plant is not over-pruned and that the healthy buds are left intact to encourage new growth. Pruning should be done to maintain the desired shape of the plant, to prevent overcrowding, and to encourage a fuller, bushier look. Generally, the plant can be pruned 3 to 4 times a year, cutting away no more than 1-third of the plant each time. It is important to remember to always use clean, sharp tools to avoid damaging the plant and to always disinfect tools after each use.

Season

Fall
Winter
Spring
Summer
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Starts Flowering

Persicaria affinis 'Superba' typically starts flowering in June.

Hardiness Map