Also known as Knotweed · 50 gardener saves
Polygonum: the varieties gardeners actually grow
Polygonum, the genus most gardeners know as knotweed. We track 4 varieties; these are the ones gardeners actually save and plant, ranked by real saves rather than catalog marketing. Each links to full care, bloom, and live price data.
The 4 most-saved Polygonum varieties
Of 4 in the catalog — ordered by how many gardeners actually grow them.
#1 most savedSilver Lace Vine
Polygonum aubertii
#2 most savedVietnamese coriander Vietnamese mint
Polygonum odoratum
#3 most savedKiss-Me-Over-The-Garden-Gate
Polygonum orientale 'Kiss-Me-Over-The-Garden-Gate'
Japanese knotweed
Polygonum cuspidatum 'Spectabile'
How to grow Polygonum
What the Polygonum varieties in our catalog actually agree on — drawn from the care records of the 4 most-grown of them, not from a generic template.
The Polygonum year
- PlantMarch, April, May, September and October75% of varieties
Plant containerized or bare-root vines in spring or fall
Do
- Water during dry spells 🌱
- Prune to maintain shape
- Provide support for climbing
- Fertilize monthly during growth
- Water deeply during dry spells 🌱
Avoid
- Overwater to prevent root rot ❌
- Allow plant to become waterlogged
- Neglect pruning
- Plant in poorly drained soil
What goes wrong with Polygonum
| Problem | What you'll see | What to do |
|---|---|---|
| Aphids | Sticky residue and distorted leaves | Use insecticidal soap or neem oil |
| Spider Mites | Fine webbing on foliage, speckled leaves | Use organic insecticidal soap and maintain humidity |
| Root rot | Wilting and blackened roots | Improve drainage and reduce watering |
| Powdery mildew | White powdery coating on leaves | Apply organic neem oil or sulfur-based fungicide |
| Powdery Mildew | White powder on leaves | Ensure good air circulation and apply neem oil |
Making more Polygonum
cuttings
- Select healthy stems in early summer.
- Cut 4-6 inch sections and remove lower leaves.
- Dip in rooting hormone.
- Plant in moist, well-drained soil.
- Keep soil moist for 6 weeks.
division
- Dig up mature plant in early spring.
- Separate root clumps with a sharp knife.
- Replant divisions immediately in prepared soil.
- Water thoroughly after planting.
Polygonum questions
How many types of Polygonum are there?
The Sow catalog tracks 4 distinct Polygonum varieties. The most popular — ranked by 50 real gardener saves — are shown first above.
What zones does Polygonum grow in?
Across its varieties, Polygonum covers USDA Zones 4–10. Individual varieties differ — each plant page lists its exact range, and Sow filters the catalog to your zone automatically.
When does Polygonum bloom?
Most Polygonum varieties bloom in summer to fall, mid-summer, late summer. Staggering early, mid, and late varieties extends the genus's season in one bed.
Which Polygonum should I choose?
Start from the most-saved varieties above — popularity across thousands of gardens is a strong signal of reliability — then filter by your zone and sun. In the Sow app you can preview any of them in a photo of your actual yard before you buy.
Keep exploring
Design with Polygonum in your own yard
Snap a photo of your space and see these varieties planted in it — sized correctly, matched to your zone, with care reminders included.
