Common mallow, Malva neglecta
Family: Malvaceae
Written by: Michelle Peterson
Posted: January 25, 2024
Description
Common mallow is native to Eurasia. It is a low growing, spreading broadleaf weed with a straight taproot that may grow deep into the soil. Young plants grow as a basal rosette and as the plant develops, its stems branch and lengthen along the soil. Additionally, its stems become thick and hairy, and the tips of the stems turn upward. The stems are round. Its leaves are 0.5-1.5 inches in diameter and are located at the end of long petioles that branch alternatively from main stems. The leaves are circular or kidney-shaped and are dark green. They have a crinkled appearance, are slightly hairy on top and bottom, and are toothed in the margins. The veins of each leaf spread from where the leaf is attached to the petiole (palmately veined).
Quick Facts
- Common mallow can survive freezing and can grow in dry compacted soils
- Common mallow grows low to the ground and can survive mowing
- Other common names include cheese weed, cheese mallow, buttonweed, and dwarf mallow
Mature common mallow plants must be dug out to manage the weed. Image credit: Howard F. Schwartz, Colorado State University, Bugwood.org
Mature common mallow plants have woody taproots that must be dug out or the weed will regrow. Image credit: Ohio State Weed Lab, The Ohio State University, Bugwood.org
Common mallow produces small five-petaled flowers throughout the growing season. Image credit: Ohio State Weed Lab , The Ohio State University, Bugwood.org
Reproduction
Common mallow produces small flowers throughout the late spring and summer. The flowers are small and have white, pink, or lavender petals. The petals have darker pink or lavender veins. The fruit are disc-shaped like a wheel of cheese or a button, with wedge shaped seed cases that break apart at maturity. The seeds are small, tan or brown and are round with a wedge-shaped scar.
Common mallow seeds germinate from spring to early autumn. The plant reproduces mainly through seed, but stems can produce adventitious roots and stem fragments can develop roots. This weed produces flowers from May until October. Although its seeds have a low germination rate, they can survive in the soil for decades. Furthermore, stems can survive the winter and regenerate in the spring through adventitious roots. In Colorado, common mallow can survive the winter and grow as a perennial plant.
Impact
Common mallow is found in lawns and other landscapes. In turfgrass lawns and landscape beds, common mallow can outcompete other plants and degrade the aesthetic value. In crops, common mallow can decrease yields and interfere with harvesting equipment. Common mallow can also act as a habitat or host for whiteflies and thrips, as well as some plant viruses. Thus, if allowed to mature to seed, common mallow may cause increasing problems in production areas.
Cultural control
If a large number of common mallow plants are present in a landscape, either planting competitive ornamentals or using wood mulch can help manage the common mallow. The mulch needs to be at least 3 inches deep.
Mechanical control
When common mallow plants are small, hand-pulling is the best option for management. Larger plants have deep woody tap roots and must be dug out. The weeds should be left to dry out day before composting. If the weeds contain mature seeds, they should either be placed in a green waste container or composted separately in a hot, moist pile. Common mallow grows low to the ground and it will survive mowing. Neither solarization nor weed flaming controls common mallow.
Biological control
There are no commercially available biocontrols for common mallow.
References
Fennimore and Bell. 2014. Principles of Weed Control, 4th Edition. California Weed Science Society
Hill, S. 2012. Malva neglecta: common mallow. The Jepson Herbarium. Available https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=32600