Weeds are plants that are growing where they are not wanted and can take over a large section of the garden or lawn if not controlled. Identifying and controlling 12 common garden and lawn weeds is made a little easier with our tips. The guide is general information only. For more advice on weeds effecting your garden visit your neighbourhood hardware or garden centre for local information and control.

According to the Commonwealth Scientific and Industrial Research Organisation, more than 3,200* invasive plant species are weeds and a new species takes root about every 18 days. Weeds are among the top three threats to Australia’s natural resources and biodiversity and cost the economy over $5 billion every year. Fortunately, most homeowners only need to deal with some of the more common varieties.

*CSIRO – Biological control of weeds https://www.csiro.au/en/research/plants/water-marine/weed-biocontrol

1. Dandelion (Taraxacum officinale)

The bright yellow flowers that transform into white puffballs as they seed make dandelions one of the easiest weeds to identify. Check out our dandelion guide for more information.

2. Chickweed (Stellaria media)

Chickweed is an edible plant that can be a useful herb but can be a nuisance in your lawn. The leaves of chickweed are small and shield-shaped with fine hairs. Check out our chickweed guide for more information.

3. Catsear (Hypochaeris radicata)

Catsears are similar in appearance to dandelions but have smaller flowers, wider leaves and longer stems. They are so named due to the dense hair that covers the leaves that look like cat’s ears. It is a perennial weed but may behave more like an annual in drier climates.

Catsears loves to grow in compacted soil or lawns that have been mowed too low so ensure you keep the mower blades high. To reduce the chance of the weed spreading remove with a trowel or spade and add organic compost or homemade compost and/or Seasol Super Compost to the soil. If the infestation becomes too great, try an organic herbicide such as EarthCare Organic WeedKiller spray which may help to control catsear.

EarthCare Organic WeedKiller spray is glyphosate-free, non-selective, contact spray so care must be taken when spraying in lawns or near your favourite plants. Follow the directions on the container and ensure that all foliage is totally covered with spray as it is a contact spray only. Repeat applications may be necessary.

4. Clover (Trifolium spp).

White clover grows close to the ground and produces many small 3-leaf clovers. Before seeding, the plant produces small, white flowers with pink centres. The best way to get rid of white clover is to pull it up manually by hand (wear gloves), trowel or spade. Check out our clover guide for more information.

5. Pennyweed or Pennywort (Hydrocotyle sp.)

Pennyweed also known as pennywort is one of the most common weeds in Australia but can be difficult to identify because it looks similar to dichondra. It has small, round leaves that resemble the coin that gives the plant its name.

Preferring to grow in moist, shady areas of the garden and lawn where it can take off, it is widespread in tropical, sub-tropical and warm-temperate climates.

Some people like the appearance of pennyweed and decide to leave it in their garden. However, if you want to remove it, your best bet is to pull it up when it is small by hand (wear gloves), trowel or spade or apply an organic herbicide such as EarthCare Organic WeedKiller spray. As Pennyweed also thrives on moisture, make sure you don’t overwater your plants or have bare spots in the garden where it can take off.

6. Oxalis (Oxalis spp)

Oxalis looks similar to white clover but produces small, yellow flowers. This perennial weed can be difficult to eliminate because of its extensive root system and rhizomes that form numerous bulbs. Check out our oxalis guide for more information.

7. Thistle 

There are a few types of thistle that call Australia home but the two common ones that effect our garden and lawn are common sowthistle or Scotch thistle (Onopordum acanthium).

Scotch thistles have tall spiny stems and leaves and produce large, mostly purple flowers. Like dandelions, thistles produce seeds with fine hairs that can blow in the wind or attach to animals or clothing.  The best way to eradicate is to remove it before it starts to flower to prevent seeds from setting. Hand weed or dig out using a spade or weeding tool. As scotch thistle has a large, long taproot, ensure to get the entire root out when removing it.

8. Bindii (Soliva sessilis)

Bindii is a low-growing, broadleaf weed that has carrot-like leaves that fan out like a rosette. In the spring, bindii produces a single flower that forms a hard seed capsule with three armoured spurs.

Bindii colonises quickly in damaged lawns and the seeds can be painful to walk on. Additionally, the spiny seeds can attach themselves to footwear, clothing and pets, establishing new infestations wherever they fall off.

The best time to eliminate bindii is in the autumn or winter, using a targeted herbicide. In late winter or spring, you can manually remove small plants before the roots get too deep by using a trowel or spade ensuring you remove the large taproot beneath the ground.

9. Winter Grass (Poa annua)

Winter grass known as a grass weed has a tufted habit and long, soft, drooping, bright green leaves. It spreads prolifically throughout winter due to the large number of seeds it produces and its spiderweb-like root system. Winter grass will also thrive in most conditions throughout Australia.

Keep your lawn well-fertilised with Seasol for Lush Green Lawns to make it more difficult for winter grass to establish itself. Remove the whole plant while it’s young and before it sets seeds. If it does set seeds there will be more weeds taking off next year. Applying pre-emergent herbicides in early spring can also be effective.

10. Summer Grass (Digitaria sanguinalis)

Summer grass known as an annual weed has soft, hairy leaves attached to long stems. It grows in bunches and has multi-branching stems that can be brown or light red.

Summer grass establishes itself in spring and can quickly colonise bare patches in lawns in warm and humid conditions. Removing summer grass by hand is effective but it will continue to re-emerge in spare unhealthy lawn areas. Improve the health and growth of your lawn by applying a premium lawn fertiliser and soil improver such as Seasol for Lush Green Lawns will make it hard for summer grass to take off in the lawn. Applying pre-emergent herbicides in mid-spring or post-emergent herbicides later on can help with larger infestations.

11. Crowsfoot  (Eleusine Indica)

Crowsfoot also known as Crabgrass is a grassy weed that has wide leaf blades that have a grass-like appearance but produce tough stems with fingers of seed heads at their tips. Crabgrass is very noticeable in a lawn because it grows faster than most types of turf.

Because crabgrass spreads so quickly, it is important to eliminate it as soon as you notice it. Mow your lawn year-round to remove weed seeds before they mature and keep your lawn growing strong, healthy and green to prevent weeds taking off. Check out the seasonal lawn care guide for more information. If crabgrass persists, apply a pre-emergent herbicide.

12. Paspalum (Paspalum dilatatum) 

Paspalum is a perennial grass weed with tufted leaves that can grow to a height of over a metre in the wild or garden beds. Paspalum produces numerous seeds in late summer that are sticky and spread by attaching to footwear and pets.

Because paspalum is hardy and lives a long time, it is difficult to get rid of it once it gets established. The best method is removing it by hand or trowel making sure you dig underneath the crown, below the soil and remove its entire root. It will be time consuming to remove but if controlled when young it is alot easier.