Glandular Smartweed Plant Care

Glandular Smartweed (Persicaria glandulosa) belongs to the Polygonaceae family within the Persicaria genus. Glandular Smartweed is native to Australia, New Zealand, temperate Asia, Europe and North America.

Glandular Smartweed displays a spreading, clumping perennial growth habit, reaching up to 1.5 ft tall with a spread of approximately 2 ft. Glandular Smartweed produces small, spiky flowers in various colors.

Leaf size: approximately 4 inches.

Persicaria glandulosa requires watering every 3–5 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.

Glandular Smartweed thrives in full sun to part shade.

Persicaria glandulosa grows best at temperatures of 50–80°F. Glandular Smartweed prefers humidity levels of 40–70%.

Moist, well-draining soil rich in organic matter. Good drainage is essential for Glandular Smartweed to prevent waterlogging, which leads to root rot and fungal issues.

Feed Glandular Smartweed every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.

Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Repot every 2-3 years in early spring. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.

Glandular Smartweed can be propagated through division, seeds. Similar propagation techniques also apply to water pepper plant care, which shares the same genus.

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Glandular Smartweed is susceptible to aphids, spider mites. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Glandular Smartweed grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Glandular Smartweed is native to Australia, New Zealand, temperate Asia, Europe and North America. In cooler regions, grow Glandular Smartweed as a houseplant or bring it indoors before the first frost.