Edging Lobelia, Annual Lobelia, Trailing Lobelia

Lobelia erinus

Family: Campanulaceae (kam-pan-yew-LAY-see-ee) (Info)
Genus: Lobelia (low-BEE-lee-a) (Info)
Species: erinus (EAR-rin-us) (Info)



Foliage Color:


Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Suitable for growing in containers

This plant is suitable for growing indoors


under 6 in. (15 cm)


6-9 in. (15-22 cm)


Not Applicable

Sun Exposure:

Full Sun


All parts of plant are poisonous if ingested

Bloom Color:



Medium Blue

White/Near White

Bloom Time:

Mid Summer

Late Summer/Early Fall

Mid Fall

Late Fall/Early Winter


Unknown - Tell us

Other details:

Unknown - Tell us

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:


Propagation Methods:

From seed; direct sow after last frost

Self-sows freely; deadhead if you do not want volunteer seedlings next season

Seed Collecting:

Allow pods to dry on plant; break open to collect seeds

Properly cleaned, seed can be successfully stored


This plant has been said to grow in the following regions:

Casa Grande, Arizona

Elk Grove, California

Knights Landing, California

Livermore, California

Oakland, California

Miami, Florida

Milton, Florida

Pompano Beach, Florida

Port Charlotte, Florida

Winter Springs, Florida

Honolulu, Hawaii

Kailua, Hawaii

New Orleans, Louisiana

Brookline, New Hampshire

Clifton Park, New York

Elizabeth City, North Carolina

Batavia, Ohio

Gibsonburg, Ohio

Georgetown, Texas

Rowlett, Texas

San Antonio, Texas

Sour Lake, Texas

Freeland, Washington

Seattle, Washington

show all

Gardeners' Notes:


On Mar 29, 2014, sunkissed from Winter Springs, FL (Zone 9b) wrote:

Trailing Lobelia in Florida does well in late winter and spring. You'll start seeing is as early as late January in the garden centers, but nout usually until Feb. and March. It does very nice as a filler in pots and will thrive until we hit summer heat and rains, then it will usually die out. There is no need to fear of it being invasive, just an annual here, maybe I should say semi annual, since it won't make it through the hot summer. That said it makes a real stand out in the spring garden, and it can take pretty cold temperatures in winter, if you can find it that early. I never pay more than a buck for a small pot since it will quickly grow and make a nice hanging basket or filler for containers. A must in my garden for spring eye candy.


On Oct 8, 2012, AmyInNH from Brookline, NH wrote:

Great luck with this in NH so long as it's shielded from the worst mid-day sun. Planted north/northeast facing and blocked from any sun past morning, it's still blooming its little guts out in mid-October. I'm mad for this each spring and have also grown it inside in windows with pretty good luck.


On Oct 8, 2012, nativelyeager from Brooksville, FL wrote:

Just a note of hope for caution....Someone posted a 'positive' saying "throw it in the ground and watch it thrive." For someone like me who loves plants but believes it's critical to protect natural ecosystems, these words set up 'red flags'. Please be careful with such plants if you are anywhere near a natural area. Any seed of any plant which can find its own way, moved by wind or water or hitch-hiking with critters (on fur or feathers or in their poop) into an area far from its native one, has the potential, when so easily propagated, to change the new habitat.


On Mar 26, 2010, otter47 from Livermore, CA wrote:

Since I adore truly royal blue flowers, this lobelia is a must for my garden. Crystal Palace, Cobalt, and Riviera Midnight are my favorite varieties. I grow it in pots, hanging baskets and in the ground (in loose, fertile soil). It grows best in the cooler months of the year and wears out if we have too many hot spells in summer. I usually buy it in six-packs but occasionally grow my own from seed. Yes, the seed is exceedingly tiny and the young plants need nurturing. I sow it in late spring to have fresh plants for autumn. If the winter is not too cold, these plants survive and bloom when the days begin to lengthen. Occasionally, I have self-sown plants crop up. Lobelia erinus is a jewel of a plant and worth the effort.


On Jun 29, 2009, darylmitchell from Saskatoon, SK (Zone 3a) wrote:

I've had mixed results with this lobelia. Last year I planted in the ground where it produced some flowers, but also looked leggy with blackened foliage. This year I put it in a container that gets morning sun and afternoon shade. I've had vigourous, healthy plants and a profusion of blooms. My guess is that it doesn't appreciate clay soil.


On May 30, 2008, Sabrina1978 from Gibsonburg, OH wrote:

I love, love, love, this annual. There are a few colors my local greenhouse carries. I like the blue moon, sky moon, half moon (in blue of course)....I like that the foliage has a more reddish hue as it ages.
.I have clay soil that is neutral to slightly alkaline. I have planted this two years in a row in hot sunny dry southern exposure here in zone 5 NW OH. It does need water in the dog days but a wonderful addition to any garden.

Very neat and compact-great color.


On May 4, 2008, yerboyhowdy from Seattle, WA (Zone 5b) wrote:

This is my favorite "throw it in the ground and watch it thrive" plant. A few minutes of work turns into a cascade of green foliege and blue flowers that asks only to be kept moist (a couple times a month chore here in Seattle), and comes back strong as ever the next year. I've had great luck with it blooming in low sun to partial shade.


On May 16, 2005, lmelling from Ithaca, NY (Zone 5b) wrote:

One of my favorite annuals. In our area Zone 5b, I use lobelia in areas that get only a couple of hours of morning sun or bright shade (to the side of a birds nest spruce and in my shade garden), and they bloom from late spring sometimes all the way through till frost! Wonderful to look out and see those bright blue flowers waving back! Favorites are Midnight Rivera and Blue Moon.


On Jul 2, 2004, punaheledp from Kailua, HI (Zone 11) wrote:

I also planted "crystal palace" some problem with germination (might be slugs) but the one that grew made it worth it. "Charming" comes to mind. It's in the ground next to a lavender alyssum, nice together. Folliage starts green, turns reddish-purple. Flowers purple-blue w/white center. will see if it survives summer heat (zone 11). Will be trying again for more of these. Tiniest seeds I've ever seen, dust is bigger.


On Mar 16, 2004, youreit from Knights Landing, CA (Zone 9b) wrote:

If there was a "Positive times 10" rating, I would choose it for this plant. I planted 'Crystal Palace' last fall, and this supposed annual is blooming AGAIN. This after a season of unusually wet weather, with freezing temps down to about 30 F a few times between precipitous days. The soil is quite clay-like, and it gets rather baked on hot, dry days like today, but there they are, those electric blue flowers and the thick green-bronze foliage, waving at me in the front yard.


On Dec 11, 2003, dogbane from New Orleans, LA (Zone 9a) wrote:

I love the electric blue color of these. In my zone, this lobelia is a cool season annual. It performs unpredictably because it can't tolerate wet, cold conditions. In dry winters it puts on a splendid display for months. Winters with lots of rain, they rot away in days.


On Oct 9, 2002, tredduk wrote:

Although in previous years this plant has never worked for me, this year it excelled. I think the answer was to put it in full sun (bearing in mind that I live in Wales (UK), so my kind of full sun has clouds in it) and I gave it good drainage, regular watering & fresh from the bag compost to root in. It spread like wildfire, covering the centre of my lawn with a constantly reflowering mass of blue which the bees and butterflies appreciated no end. Despite previous failures then, I think I've cracked it & will definately pursue this in future seasons...particularly in a cascade of pots I think...but that's a comment for the future if it works.


On Nov 7, 2001, LerayJ wrote:

Light Requirements:zone 9-10 = SHADE TO PART SHADE
Hight: 5 inches