Customer Service Hours
Mon-Fri 8-4 MST
Features
Family
Campanulaceae
Native
Africa
Life Cycle
Perennial
Plant Height
Short (Under 12")
Flower Color
Blue
Bloom Season
Spring to frost
Further Information
Plant Characteristics
- Attracts Beneficial Insects
- Attracts Pollinators
- Good for Containers
Plant Resistance
Deer Resistant
About Cambridge Blue Lobelia Seeds
Lobelia erinus
½" light blue flowers heavily massed above low-growing foliage
Planting Lobelia
Plant Spacing
Sow in groups of 12–20 seeds, 4"–6" apart
Hardiness Zones
10, 11
Light Required
Full sun to part shade
Plant Height
Short (Under 12")
Planting Depth
Press lightly into surface
Planting Details
| Seed Depth | Press lightly into surface |
|---|---|
| Seed Spacing | Sow in groups of 12–20 seeds, 4"–6" apart |
| Thinning | Not required. |
| Germination | 15–20 days |
| Start Indoors | RECOMMENDED. 8 to 10 weeks before your average last frost date. Ideal soil temperature for germination is 60°–70°F. |
| Direct Sow | 1 to 2 weeks after your average last frost date. In Mild Climates, sow in late summer for winter color. |
Find Your Frost Date & Grow Zone
Average First Frost Date
October 19
Average Last Frost Date
May 19
Your Hardiness Zone is
5b
Send Your Recommendation
Total 5 star reviews: 5 Total 4 star reviews: 0 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 2
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Rating
Which best describes you as a gardener?
8 reviews
- Jennifer S.Verified BuyerRated 5 out of 5 stars3/6/26Cambridge blue lobelia seeds. Bought for a few years now.
Grows really well! True Cambridge blue has been difficult to find in my area. Great germination indoors and great growth in the garden.
Which best describes you as a gardener? IntermediateBIBotanical Interests3/10/26Hey Jennifer,
We're so thrilled to hear you've been having such great success with our Cambridge Blue Lobelia Seeds for years now! You're absolutely right that true Cambridge blue can be hard to find - we love that our seeds are giving you that authentic beautiful blue color you're looking for. It's wonderful to hear about the excellent germination rates indoors and how well they're thriving in your garden. Thank you for being such a loyal customer and for sharing your continued positive experience with us. Keep on growing 🌻️
- LindaVerified ReviewerRated 1 out of 5 stars7/29/25Cambridge Blue
Sorry, but this is not 'Cambridge Blue'. It is not the lovely palest blue that 'Cambridge Blue' is. It is a nondescript medium blue. Nothing special. Very disappointing.
Which best describes you as a gardener? IntermediateBIBotanical Interests8/15/25Hey Linda,
Thank you so much for taking the time to share your thoughts. A flower might not bloom in the color you were expecting for several natural reasons, and it doesn’t necessarily mean something is wrong.
Soil conditions can play a role; certain flowers, like hydrangeas, change color based on soil pH and mineral content. Weather and temperature fluctuations, such as heatwaves or cold snaps, can impact pigment development and lead to muted or altered flower colors.Your feedback is invaluable to us, and we are committed to ensuring your experience is positive. Please feel free to reach out to our Customer Support team with any questions. We're here to help. Thank you once again for your input. Keep on growing 🌻️
- Judy B.Verified BuyerRated 3 out of 5 stars8/17/243 Stars
Seeds have yet sprout; I planted them two weeks ago.
Which best describes you as a gardener? Intermediate - Jessica s.Verified BuyerRated 5 out of 5 stars7/13/245 Stars
1st time growing this flower and will definitely do it again it's so pretty.
Which best describes you as a gardener? Professional - Verda D.Verified BuyerRated 5 out of 5 stars11/28/235 Stars
my baby plants made me so happy to watch them grow!