Attract butterflies to your yard with the beautiful blue and purple blooms of annual lobelia.
Youll also find downy lobelia (Lobelia puberula), a fall-blooming perennial wildflower with fuzzy leaves.
The versatility of lobelia doesnt end there.
Credit: Justin Hancock
There are also severalLobelia erinuscultivars to choose fromeach with slightly different growth habits and requirements.
The cascading throw in spills like a sapphire waterfall from window boxes or pots.
it’s possible for you to even find compact and trailing lobelia with magenta or white flowers.
Credit: Justin Hancock
There is, in short, a lobelia for almost any landscape.
Some species of lobelia (likeLobelia cardinalis) are also considered toxic to dogs, cats, and horses.
Just loosen up the soil and dig a hole only slightly larger than the plants root ball.
Credit: Justin Hancock
Wiggle the plant out of its nursery pot and tease apart the roots.
Tamp the soil down as you work to remove any air pockets and then water thoroughly.
UnlikeLobelia cardinaliswhich grows beautifully in boggy soilannual lobelia is likely to rot if soil conditions are too wet.
Credit: Justin Hancock
In hotter climates, without protection, the peak afternoon sun may cause annual lobelia to shrivel.
They are not frost tolerant and will likely die with exposure to temperatures below 40 degrees Fahrenheit.
For the amount to use, follow product label instructions.
Credit: Justin Hancock
Pruning
SinceLobelia erinusis considered an annual plant in most regions, pruning and deadheading are not necessary.
First, create a hole in the new pot slightly larger than the plants root ball.
Fungal disease and stem rot are common ailments (typically triggered by too much moisture).
Credit: Peter Krumhardt
Corn earworms can also be a problem and may make the plant more vulnerable to fungal diseases.
If you see them, remove them manually or use insecticide.
Before you plant them outside,harden them offwith gradual doses of exposure to outdoor temperatures.
Credit: Edward Gohlich
It grows approximately 10 inches tall and 8 inches wide in Zones 9-11.
It trails 6 to 12 inches and can spread 12 to 24 inches in Zones 9-11.
‘Magadi Blue’ Lobelia
Lobelia erinus’Magadi Blue' offers better heat tolerance than most lobelias.
Credit: Peter Krumhardt
It offers bi-color, soft-blue flowers marked with a white throat.
It grows 6 to 10 inches tall and spreads 8 to 12 inches in Zones 8-11.
It tends to grow to only 5 inches tall and spread just 8 inches in hardiness Zones 9-11.
Credit: Peter Krumhardt
It trails 6 to 8 inches and spreads 10 to 12 inches in Zones 10 and 11.
Companion Plants for Annual Lobelia
Loosestrife
These vigorous growersare beautiful additionsto the garden.
They vary from tall, stately plants suitable for borders to others that can be planted as creeping groundcovers.
Credit: Cynthia Haynes
Flowers, too, vary from tight spikes of 1/2 inch to 1-inch cups carried alone or in whorls.
Humus-rich, moisture-retentive soil is recommended; some varieties enjoy wet soil and ample water.
Several sorts may become aggressive and need to be corralled.
Credit: Denny Schrock
‘Firewitch’ cheddar pinks are hardy in Zones 38 and grow just 6 inches tall.
By summer, pansies bloom less and their foliage starts to brown.
But that’s part of their charmthey are an ephemeral celebration of spring!
Credit: Peter Krumhardt
Your plants may also take a break from blooming during especially hot weather.
As temperatures drop, it should start blooming again.
In perfect soil and climate conditions, lobelia plants can spread, but will not do so aggressively.
Credit: Illustration by Gill Tomblin
If plants pop up in places you dont want them, simply pluck them out of the ground.
Lobelia erinus.North Carolina Extension Gardener Plant Toolbox.
ASPCA Toxic and Non-Toxic Plants.
