Place weeds into the garbage, not into compost bins. Once the seeds have formed (usually in late winter or very early spring) but are still green, hand weed to remove the entire plant and immature seeds. The plant dies back in late summer, leaving behind the burrs, which contain the seeds for the next autumn’s growth.Ĭontrol: Treat infested lawns in autumn or winter before burrs form using a systemic herbicide for this weed (sold as Bindii and Clover Weeder), which does not kill lawn grass. Life cycle and reproduction strategies: Leaves appear in autumn and winter and quickly begin to flower and set seed. Small green flowers form in the middle of the plant and quickly form sharp burrs, which stick into bare feet, shoes and animal’s paws. Don’t attempt to weed if you suffer from asthma or hay fever.ĭescription: A small, low-growing annual weed with a rosette of bright green, fern-like leaves commonly found in grass and compacted soils. Re-treat seedlings or hand-weed regularly. Treat plants before flowering to reduce spread. Responds well to glyphosate-based herbicides. The seeds spread by wind, water, on clothes and in pet fur.Ĭontrol: Difficult to control by weeding alone. Also regrows from roots left behind if the plant isn't fully pulled out. New plants may grow and start flowering within 2-3 weeks. Life cycle and reproduction strategies: Reproduces rapidly from seed. Commonly found growing from cracks in walls and paving, this weed can trigger asthma and hay fever attacks due to the pollen it produces, and may also irritate skin. Flowers cluster along the pink or red leafy stems. Cover weeded areas with mulch.Īsthma weed, pellitory, sticky weed ( Parietaria judaica)ĭescription: Small, perennial, many-branched weed (can reach 1m high but is usually smaller) with round, green, slightly hairy leaves that feel sticky, and small, green, pollen-filled flowers which appear throughout the year, but particularly in spring. Watch for regrowth and remove any seedlings or suckers. Dig out the entire clump, removing all tubers. Also spreads via berries.Ĭontrol: Remove flowers and fruit and bag them up so they don’t spread. Life cycle and reproduction strategies: Grows year round from persistent white tubers and rhizomes. Once grown as an ornamental, it is now an invasive weed.
It produces spires of white, perfumed flowers from spring to autumn followed by berries that ripen to red. Repeat applications are normally needed.ĭescription: A clumping perennial plant with long, arching, spined stems covered with small, bright green, needle-like leaves giving the plant a fern-like appearance.
Remember, when using herbicides, always follow the recommended application rates and times.
Here are some of the weeds most commonly encountered in Sydney or other temperate and coastal gardens, with tips on how to recognise and control them using chemicals or physical methods, or both. Identifying a garden weed, and understanding its growth and life cycle, can help you work out a control strategy.