knotweed

Knotweed (Persicaria microcephala 'Red Dragon') should be watered regularly throughout the growing season. In general, it should be given about an inch of water per week (either from rainfall or from manual irrigation) to keep soil evenly moist but not wet. During prolonged periods of hot weather, additional water may be necessary. However, be sure not to over-water, as this can lead to root rot. Knotweed also appreciates regular misting with water, especially during peak summer months.

Knotweed (Persicaria microcephala 'Red Dragon') likes full sun, or at least 6 to 8 hours of direct sunlight each day. This plant does best in regions that enjoy a long period of uninterrupted sunshine throughout the summer, such as the upper Midwest and mid-South regions of the United States. During the late spring, summer and early fall months, the hours of direct sunlight for knotweed should range from roughly 9 am to 5 pm. As daylight hours diminish with the approach of winter, knotweed should continue to receive direct sunlight for at least 4 hours each day. To ensure that knotweed receives ample sunlight, place it in an area that does not receive too much shade from trees, walls, or other large plants.

Knotweed (Persicaria microcephala 'Red Dragon') should be pruned during the late spring or early summer. Pruning should be done to remove dead, damaged or diseased stems and branches, and to shape the plant as desired. It's best to only remove 1/3 of the stems at a time, and begin by cutting back the oldest, largest branches. Pruning should generally occur every 3 to 5 years.