Morning glory - purple (Ipomoea indica)

Also known as: blue morning glory

Purple morning glory is a vigorous climber with purple flowers that can smother the ground and grow high into the canopy. It outcompetes native plants and is poisonous to people and animals.

Profile

How does this weed affect you?

Purple morning glory is a vigorous climber that forms a dense ground cover or climbs over other vegetation, sometimes high into the canopy. It:

smothers and outcompetes native plants
reduces habitat for native plants and animals
invades crops (including sugar cane)
is poisonous to people
may be toxic to horses, cattle, sheep and goats.

Invasion and establishment of exotic vines and scramblers has been identified as a key threatening process for many vulnerable and endangered species in NSW. Purple morning glory is one of the main species listed as a threat.

Livestock health

Purple morning glory may contain calystegines which are mildly poisonous to horses, cattle, sheep and goats.

Human poisoning

The seeds are poisonous to humans and can cause nausea and temporary vision problems. However, plants rarely produce seeds in Australia.

What does it look like?

Purple morning glory is a scrambling perennial vine with long, twining stems, It grows quickly and can reach up to 15 m high into tree canopies.

Leaves are:

4–17 cm long and 3–15 cm wide
heart shaped or with 3 deep lobes
pointed at the tips
hairy on both sides with short hairs on the upper side and silky dense hairs underneath
on stalks 3–13 cm long
alternate along the stem.

Flowers are:

blue to purple with a darker coloured throat in the morning then fading to pink in the afternoon
funnel shaped with 5 fused petals
5.5–7.5 cm long and 6.5–8.0 cm wide
in clusters of 3–12 on stalks up to 20 cm long
open for only one day
mainly present from spring to autumn.

Seedpods are:

a capsule with 3 chambers
10 mm in diameter
roundish.

Seeds are:

rarely produced in Australia.
4–5 mm wide
egg-shaped
hairless with a warty-textured surface.

Stems are:

hairy when young
occasionally release a white sap when cut.

Roots are:

fibrous on younger plants
a woody, branched crown.

Similar looking plants

Purple morning glory looks like other vine weeds including:

Common morning glory (Ipomoea purpurea), which has smaller flowers (up to 5 cm long and 4 cm in diameter) that have a lighter coloured throat.
Coastal morning glory (Ipomoea cairica), which has smaller leaves with 5-7 lobes.
Moonflower (Ipomoea alba), which has large white flowers that open at night.
Laurel clock vine (Thunbergia grandiflora), which has opposite leaves.

Where is it found?

Purple morning glory grows in coastal areas of NSW especially around the Greater Sydney and North Coast regions. Scattered plants have also been found in the North West region. It used to be widely grown as an ornamental garden plant.

It is native to South America.

What type of environment does it grow in?

Purple morning glory grows in moist tropical, subtropical and temperate climates. It tolerates a wide variety of soil types though it grows best in moist nutrient-rich soils. It does not grow in temperatures below 7ºC. Plants have been found growing:

in disturbed areas including along roadsides and urban areas
along rainforest margins and in disturbed forests
in woodlands
amongst crops.

How does it spread?

By seed

Purple morning glory can set viable seeds in NSW. Seeds can be spread by people dumping garden waste.

By plant parts

Purple morning glory stems grow roots from nodes that contact the soil. Broken stems and roots can spread:

in dumped garden waste
in moving water
by animals and vehicles
stuck to machinery such as slashers.

References

Harden, G. J., McDonald, W. J. F., & Williams, J. B. (2007). Rainforest climbing plants. Gwen Harden Publishing.

Identic Pty Ltd. and Lucid central (2016). Environmental Weeds of Australia Fact sheet: Ipomoea indica. Retrieved 10 October 2023 from: https://keyserver.lucidcentral.org/weeds/data/media/Html/ipomoea_indica.htm

McKenzie, R. (2012). Australia's poisonous plants, fungi and cyanobacteria: a guide to species of medical and veterinary importance. CSIRO.

Muyt, A. (2001). Bush invaders of South-East Australia: a guide to the identification and control of environmental weeds found in South-East Australia. RG and FJ Richardson.

Office of Environment and Heritage. (2017). Invasion and establishment of exotic vines and scramblers – profile. Retrieved 10 October 202 from https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=20052

PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 10 October 2023 from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Ipomoea~indica

More information

Control

Successful weed control relies on follow up after the initial efforts. This means looking for and killing regrowth or new seedlings. Using a combination of control methods is usually more successful.

To manage purple morning glory control plants as soon as possible before the infestation spreads and check treated areas and control regrowth and new seedlings.

Physical removal

Climbing stems can be cut and left hanging to wither and die. Make sure no cut stems have contact with the soil. Dig out the roots carefully as they will regrow from parts left in the ground.

Chemical control

Spot spraying

Apply to actively growing plants. Cover all of the foliage with the herbicide mix. This method is best for low growing vines.

Stem scraping

This method reduces the risk of damaging the plants that the vines are growing over. Cut stems and ensure no parts of the plant above the cut are touching the ground. Lightly scrape the stems along 20 – 30 cm from the cut. Do not scrape all the way around. Apply herbicide to the cut and scraped parts of the stem within 15 seconds of cutting.

Cut stem method

Cut stems close to the ground, preferably within 10 cm from the soil. Apply herbicide gel to the cut surface connected to the soil within15 seconds of cutting. Climbing stems can be left in place to wither and die. If there are any stems touching the ground, collect them and either take them off-site for disposal, or leave them on site to dry out without contacting the soil.

Disposal

Contact your local council for advice on how to dispose of this plant

Herbicide options

WARNING - ALWAYS READ THE LABEL
Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this information. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website www.apvma.gov.au

See Using herbicides for more information.

PERMIT 9907 Expires 31/03/2025
Glyphosate 360 g/L (Various products)
Rate: 200 mL per 10 L of water
Comments: Spot-spray for seedling control.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

PERMIT 9907 Expires 31/03/2025
Glyphosate 360 g/L (Various products)
Rate: 1 part glyphosate per 1.5 parts water
Comments: Stem scraping application.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

PERMIT 9907 Expires 31/03/2025
Glyphosate 360 g/L with Metsulfuron-methyl 600 g/kg (Various products)
Rate: 200 mL glyphosate plus 1.5g of metsulfuron-methyl in 10 L water
Comments: Spot spray application
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

Dichlorprop 600 g/L (Lantana 600®)
Rate: 1 L in 200 L of water
Comments: Completely wet all leaves and stem of target plants
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate

Picloram 44.7 g/L + Aminopyralid 4.47 g/L (Vigilant II ®)
Rate: Undiluted
Comments: Cut stem application. Apply a 3–5 mm layer of gel for stems less than 20 mm. Apply 5 mm layer on stems above 20 mm .
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate

Biosecurity duty

The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.

Area	Duty
All of NSW	General Biosecurity Duty All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.

For technical advice and assistance with identification please contact your local council weeds officer.

Reviewed 2024