Common mallow

About

Common mallow is a sprawling weed from Europe and Asia with round, scalloped leaves that shows up in thin lawns and garden beds. It acts as an annual, biennial or short-lived perennial, and its deep taproot makes older plants hard to pull.

Also called cheeseweed, cheese plant, buttonweed, dwarf mallow, mallow

How to identify it

Look for

Leaves are round to kidney shaped, on long stalks, with shallow lobes and rounded teeth, and they feel slightly rough from short hairs. Stems sprawl up to about 2 feet from a deep, woody taproot. Small white to pale pink five-petaled flowers, often with violet veins, become flat, round fruits shaped like a wheel of cheese.

Look-alikes

Ground ivy also has round, scalloped leaves, but its leaves are opposite on square stems and smell minty; mallow leaves are alternate and rough.

Where it grows

Thin lawns, planting beds, gardens, crop fields, orchards and waste areas.

When

Seeds sprout from mid-spring to early fall whenever the soil is moist; it flowers from early summer to mid-fall and can stay green all year in mild areas.

How it spreads

Seed only, from cheese-wheel fruits with 10 to 20 seeds; the tough seed coat lets seeds wait in the soil for years.

Most common in

What to do, gentlest first

Start at the top. Weed killers are a last step; always read and follow the label.

1. Thick turf and full beds Prevent

   Keep the lawn dense and beds planted so bare spots don't invite it; remove plants before they flower and seed.

2. Pull while it has four or fewer leaves By hand

   Pull seedlings with four or fewer true leaves, before the taproot turns woody. For older plants, cut the taproot below the soil with a hoe or weeding knife.

   Control has to get the root, not just the top growth.

3. Mulch at least 3 inches Barrier

   At least 3 inches of bark or wood chips keeps most seedlings from coming up. Solarization and flaming don't work well on mallow.

4. Burn down seedlings with a contact spray Organic spray

   Horticultural vinegar (acetic acid), fatty-acid soap, pelargonic acid or clove-oil sprays burn what they touch within hours. They work best on very young seedlings in warm, sunny weather, and you will need to repeat, because they don't move into roots and bigger plants regrow.

   They kill any plant they touch, so shield crops. Strong vinegar can burn skin and eyes; wear goggles and gloves and follow the label.

5. Limited options; pull instead Conventional spray

   Glyphosate does not control mallow well. In lawns, 2,4-D gives only partial control on young plants, and pre-emergents such as oryzalin or pendimethalin give partial control.

   Read and follow the label. Many lawn weed killers also kill or damage vegetables and flowers, so keep spray and drift off garden plants.

Uses, wildlife and pets

Edible?

NC State Extension notes the leaves and seeds are edible, with mature seeds cooked like a grain. Only eat plants you are sure of, from ground that hasn't been sprayed, which is rare for lawn weeds.

Not 100% sure? Don't eat it. Never pick from ground that may have been sprayed, or along roads and railways.

For wildlife

The flowers draw bees and butterflies (NC State).

Pets

Not listed by the ASPCA.