Also known as Beardtongue · 3.1k saves
Penstemon
Penstemon, the genus most gardeners know as beardtongue. We track 49 varieties; the ones most used by real gardeners.
The 24 most-saved Penstemon varieties
See all 49 Penstemon varieties →Search this genus →
5 species of Penstemon
Each one is a parent of the varieties above.
Track your Penstemon in Sow
Save the Penstemon you grow and get care reminders timed to your zone.
How to grow Penstemon
Whats common across all Penstemon varieties in our catalog — drawn from the care records of the 40 most-grown of them.
The Penstemon year
- DeadheadJune and July95% of varieties
Deadhead spent flowers to prolong bloom, but leave some to self-seed.
- PruneFebruary and March57% of varieties
Cut back spent flower stalks after blooming; trim lightly in late winter/early spring.
- Spring CleanupFebruary and March50% of varieties
Cut back any remaining old stems before new basal growth emerges.
- DivideMarch and September40% of varieties
Divide mature clumps every 3-4 years to renew vigor
- MulchMarch33% of varieties
Apply a thin layer of gravel mulch to ensure excellent drainage around the crown.
Do
- Water deeply during dry spells 🌱
- Apply a balanced fertilizer in spring
- Water regularly during dry periods 🌱
- Prune after flowering to encourage bushiness
- Deadhead spent flowers to encourage more blooms
Avoid
- Avoid overwatering to prevent root rot ❌
- Overwater, which can cause root rot ❌
- Overwater to avoid root rot ❌
- Allow soil to become waterlogged
What goes wrong with Penstemon
| Problem | What you'll see | What to do |
|---|---|---|
| Aphids | Sticky honeydew and distorted leaves | Use insecticidal soap or neem oil |
| Spider mites | Fine webbing and stippled leaves | Introduce natural predators or spray with water |
| Spider Mites | Fine webbing and speckled leaves | Increase humidity and use insecticidal soap |
| Powdery mildew | White powder on leaves | Apply fungicide or improve air circulation |
| Root rot | Wilting and yellowing leaves | Ensure well-draining soil and reduce watering |
| Powdery mildew | White powdery coating on leaves | Improve air circulation and apply organic fungicide |
| Powdery Mildew | White powdery coating on leaves | Improve air circulation and apply fungicide organic or chemical |
Making more Penstemon
Cuttings
- Select healthy semi-hardwood stems in late summer.
- Dip cut end in rooting hormone.
- Insert into moist potting mix and keep humid for 6 weeks.
Seed
- Collect seeds in late summer when capsules are dry and brown
- Sow seeds outdoors in fall for natural cold stratification
- Or, cold-moist stratify in the refrigerator for 30-60 days
- Sow indoors in early spring on a sterile seed mix
- Germination occurs in 2-4 weeks
Penstemon questions
How many types of Penstemon are there?
The Sow catalog tracks 49 distinct Penstemon varieties. The most popular — ranked by 3.1k real gardeners — are shown first above.
What zones does Penstemon grow in?
Across its varieties, Penstemon 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 Penstemon bloom?
Most Penstemon varieties bloom in late spring, late spring to early summer, early summer. Staggering early, mid, and late varieties extends the genus's season in one bed.
Which Penstemon 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.