Morning glories: So much more than just pretty flowers

The iconic tall or common morning glory
(I. purpurea) is a garden favorite around the world.

Iconic garden morning glories

When most people think of morning glories, it's the tall or common morning glory (Ipomoea purpurea) that they envision. It's a vine native to Mexico, Central and South America, but its beautiful blossoms and vigorous growth even in poor conditions have made it a garden favorite around the world. There are hundreds of named cultivars.

Each delicate flower lasts only one day and they look best in the morning when they first open; hence the name "morning glory."

There are many cultivars of the common morning glory (I. purpurea) with colors ranging from pink to purple.

The native range of the common morning glory (Ipomoea purpurea).

But as you'll see, there is much more to the "Morning glory story." 

Florida's morning glories

There are 29 species of morning glory (Ipomoea spp.) that occur in Florida, but only 13 are native. A link to The Atlas of Florida Plants is included for each native species where you can see its range within Florida, and in most cases, some photos. 
Moonflower (I. alba)
Tievine (I. cordatotriloba)
Scarletcreeper (I. hederifolia)
Beach morning glory (I. imperati)
Oceanblue morning glory (I. indica)
Whitestar (I. lacunosa)
Larger-root morning glory (I. macrorhiza)
Man-in-the-ground (I. microdactyla)
Man-of-the-earth (I. pandurata)
Railroad vine (I. pes-caprae)
Saltmarsh morning glory (I. sagittata)
Rockland morning glory (I. tenuissima)
Beach moonflower (I. violacea)

One species is invasive in Florida. Water spinach (I. aquatica) is a floating plant and its leaves are edible. For more information on invasive species, see Florida Invasive Species Council.

Moonflower (I. alba) 

The moonflower is a night-blooming morning glory that's pollinated by moths. Its white blooms are visible to the moths in the dark. When the sun rises, the flowers begin to wilt. Their work is finished for the day. This is an easy-to-grow, vigorous, salt-spray-tolerant, long-lived perennial and should be used only in wilder landscapes where its climbing will not be a problem. Here is its FNPS plant profile with more details and a link to native plant vendors that have it in stock.

In an odd bit of history, the moonflower sap was used for vulcanization of the latex of Panama rubber tree (Castilla elastica) to rubber. These two species are often found together in Central and South America. As early as 1600 BCE, the Olmecs produced rubber balls used in a Mesoamerican ballgame.

Moonflower (I. alba) is a night-blooming morning glory that's pollinated by moths.

Moonflower (I. alba) native range includes much of South America.

Railroad vine (I. pes-caprae) 

Railroad vine or beach morning glory (I. pes-caprae)

The Plant Atlas of Florida, my go-to resource and authority for names and nativeness, argues that what we have in Florida is a subspecies: (Ipomoea pes-caprae subsp. brasiliensis). (Click the link to find out why.) Kew Gardens and others do not agree. Whatever taxonomists call it, this is a tough, perennial vine that is a pioneer species on sandy beaches and dunes. The seeds float in the water and so wash up on said beaches. 

This vine is pan-tropical and has a huge native range around the world. It's highly recommended for dry sandy habitats. It will spread, so use in wilder areas of the landscape. Read its FNPS plant profile for more information and also a link to native plant vendors that have it in stock. The species epithet means "goat's foot" and this relates to the shape of the leaf looking like an imprint from a goat's hoof. 

Railroad vine (I. pes-caprae) is pan-tropic. Its range includes tropics and subtropics around the world!

Sweet potatoes (I. batatas) growing in
a raised bed in South Florida surrounding
some cassava shrubs (Manihot esculenta).

Sweet potato (I. batatas): an important summer crop

Sweet potatoes are native to Mexico, Central America and northern South America and they grow very well in Florida's hot, wet summers. Plant slips (sprouts from tubers) in early spring, because it takes four months for the tubers to develop. In warmer sections, it could grow as a perennial, but it's best to remove it and replant new slips in freshly composted soil to reduce problems with pests.

We've included full instructions in our peer-reviewed book, "Organic Methods for Vegetable Gardening in Florida."

An impressive sweet potato harvest by Man in Overalls: 16 pounds from one plant!

Range for sweet potato (I. batatas) includes Mexico, Central and northern South America.

Historical note: Before the arrival of Europeans to the Americas, sweet potato was grown in Polynesia. A common hypothesis is that tubers and/or vine cuttings were brought to central Polynesia by Polynesian wayfinders who had traveled to South America and back, and then spread from there across Polynesia to Easter Island, Hawaii, and New Zealand. 

In 1778, the English explorer Captain James Cook was the first European to travel to the Hawaiian Islands where he and his botanists collected samples of the sweet potatoes with tubers that were 20 pounds, so they had arrived with the Polynesians after their contact with South Americans. The samples collected by Cook's botanists are now stored at Kew Gardens in England and they are being studied to find more information about their origin. This is proof of their contact between these peoples well before the Europeans came.

Dodder (Cuscuta spp.)
is totally parasitic. 

Dodder

Also, in the morning glory family (Convolvulaceae) is the parasitic dodder (Cuscuta spp.). There are ten species that occur in Florida and nine are natives according to the Atlas of Florida plants. These plants do not photosynthesize and are completely dependent on other plants. When a dodder seed sprouts it sends out a long strand that twirls in the air until it hits something and then, if it's a plant, it wraps itself around the stem and produces haustoria (root-like structures) that invade the host-plant cells. The hyphae or filaments of the haustoria hijack the host's nutrient transport system, transferring food and water back into the dodder plant. 

So morning glories and their relatives provide an interesting selection of beautiful, useful, and weird plants that have played important roles in human history.

Green Gardening Matters,
Ginny Stibolt