You can reduce weed growth in lawns significantly by following good management practices and understanding weed growth patterns. Improper fertilization, irrigation or mowing practices make it easy for weeds to invade even an established lawn. Identify the type of weeds plaguing your yard before beginning a control program.
Annual Grassy Weeds
Eradication of weeds is not a realistic or necessary goal. Some weeds develop even in a well-cared-for lawn. Healthy grass in fertile soil discourages weed growth. Hand weeding throughout the year may be all that is necessary when good management techniques are practiced. Hand weeding is especially useful to prevent the spread of sedges, dandelion, spurge, creeping wood sorrel, dallies-grass and Bermuda grass. Remove the weeds when they are young before they spread, grow seed or develop rhizomes. A dandelion fork or fishtail weeder is useful for removing weeds with a thick taproot.
Bermuda grass and dallis-grass are perennial grass weeds which establish themselves in lawns that are mowed too closely, are overwatered, have compacted soil or are subject to excess heat and sun. Spurge grasses, knotweed, burclover and black medic are broadleaf weeds that grow in lawns with low nitrogen fertility, compacted soil or are closely mowed and have open areas. Annual and perennial sedges become established in lawns that are overwatered and have poor drainage. Excess sun and heat as well as nearby infestations also cause sedge growth.
The weed seeds are already in the garden soil. They wait for just the right temperature and moisture conditions. So, when you plant your seeds, the weeds race out of the ground before whatever you planted can even get started.
“The weed is able to grab those resources before the vegetable plant can get them, so they tend to grow a little faster and a little better than the vegetable does,” Miller explained.
Seeds in the breeze
My friend Tim Miller is a researcher at Washington State University working to help stop weeds from making life difficult for plants we would rather have. Sometimes, weeds are bullies to other plants.
Dandelions are one kind of perennial. Each dandelion fuzz ball has as many as 100 seeds that travel in the wind. If a dandelion plant makes 10 flower heads, that’s 1,000 seeds waiting to sprout wherever they land. How many dandelions do you think you have in your lawn? If there are 50 plants, just think of those 50,000 new dandelions that can sprout from all those seeds. It’s no wonder weeds are so hard to control.
Sometimes gardeners help their vegetables by growing them in pots and then transplanting them into the garden. That gives the veggie a head start against the weed.
A race to the top
Overly sunny or shady locations
Mow higher. Raise your mowing height. Although many homeowners love the look of a closely cropped lawn, mowing too low can lead to a thin turf structure and cause weeds to creep in seemingly overnight.
Wet/soaked portions of the lawn
Areas where the lawn meets concrete (e.g. along driveway and sidewalk edges)
Invest in weed control. Weed Man’s professional lawn care programs include regularly scheduled treatments for control of broadleaf weeds. Weed control works by its ability to mimic natural growth hormones, called auxins, that are found in broadleaf plants. Auxins are absorbed through the leaves of the plants and then translocated to the meristems. Uncontrolled, unsustainable growth ensues, causing the stems to curl-over, the leaves to wither, and eventually resulting in plant death.
Fertilize regularly. A thick, healthy lawn is the absolute best defense against unwanted weeds. This is because a dense turf structure crowds out additional growth, making it difficult for weeds to sprout.
Thinning areas of the lawn