Also known as Jacob's Ladder · 214 saves
Polemonium
Polemonium, the genus most gardeners know as jacob's ladder. We track 10 varieties; the ones most used by real gardeners.
The 9 most-saved Polemonium varieties
Browse all 10 Polemonium varieties →
4 species of Polemonium
Each one is a parent of the varieties above.
Track your Polemonium in Sow
Save the Polemonium you grow and get care reminders timed to your zone.
How to grow Polemonium
Whats common across all Polemonium varieties in our catalog — drawn from the care records of the 10 most-grown of them.
The Polemonium year
- DivideApril and October90% of varieties
Divide clumps every 3-4 years to maintain vigor
- DeadheadJune and July60% of varieties
Remove spent flower stalks to encourage rebloom and neatness
- MulchApril and May60% of varieties
Apply organic mulch to keep roots cool and conserve moisture
- PruneJune–August50% of varieties
Cut back foliage by half after initial bloom to refresh plant
- Spring CleanupMarch50% of varieties
Remove dead or damaged foliage before new growth begins
- PlantApril, May, October and November40% of varieties
Plant in spring or early fall in moist, well-drained soil
- FertilizeMarch and April40% of varieties
Apply a balanced, slow-release fertilizer in early spring
Do
- Water regularly to keep soil moist 🌱
- Mulch around plants to retain moisture
- Mulch to retain soil moisture
- Divide every 3–4 years for renewal
- Water consistently during dry periods 🌱
Avoid
- Avoid overwatering to prevent root rot ❌
- Avoid dry or overly sunny locations ❌
- Don't let soil dry out completely
- Avoid heavy, compacted soils
What goes wrong with Polemonium
| Problem | What you'll see | What to do |
|---|---|---|
| Aphids | Sticky residue and distorted leaves | Spray with neem oil or insecticidal soap |
| Slugs and snails | Large, ragged holes in the tender spring foliage and silvery slime trails. | Apply iron phosphate bait around the base of the plant or handpick them during damp evenings. |
| Spider mites | Fine webbing on the foliage and stippled, yellowing leaves during hot, dry spells. | Blast the undersides of the leaves with a sharp stream of water or apply insecticidal soap. |
| Leafminers | Winding, white or tan trails within the leaves. | Remove and destroy affected leaves. Usually cosmetic. Spinosad-based organic insecticides can be effective if sprayed early. |
| Powdery mildew | White powder on leaves | Improve air circulation and apply fungicide |
| Root rot | Wilting, yellowing leaves | Improve drainage and reduce watering |
| Powdery Mildew | White powdery coating on leaves | Improve air circulation and apply fungicide if necessary |
Making more Polemonium
Division
- Dig up mature clumps in early spring.
- Separate smaller sections with a sharp knife or spade.
- Replant divisions immediately at same depth.
- Water thoroughly after planting.
- Repeat every 3-4 years for vigor.
Seeds
- Sow seeds on moist soil surface in fall or early spring.
- Keep soil consistently moist.
- Germination occurs in 2-3 weeks.
- Thin seedlings to proper spacing after emergence.
Polemonium questions
How many types of Polemonium are there?
The Sow catalog tracks 10 distinct Polemonium varieties. The most popular — ranked by 214 real gardeners — are shown first above.
What zones does Polemonium grow in?
Across its varieties, Polemonium covers USDA Zones 4–9. Individual varieties differ — each plant page lists its exact range, and Sow filters the catalog to your zone automatically.
When does Polemonium bloom?
Most Polemonium varieties bloom in late spring, early spring, late spring to early summer. Staggering early, mid, and late varieties extends the genus's season in one bed.
Which Polemonium 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.