organic weed control for lawn

Asked August 28, 2017, 12:02 PM EDT

i avoid using chemicals to treat my lawn. i manually remove dandelions and the crabgrass that invades my flower beds and tree mulch rings. except for the regular mowing, l dont touch the clover that grows and instead allow the bees and skipper butterflies to enjoy the clover blooms. however the crab grass is sprouting up more and more in the lawn, and i'd like to address the issue before it gets completely out of control. i typically aerate and overseed my lawn in the fall. can you recommend organic weed control? if you can't recommend specific products, can you recommend what i should look for in an organic weed control? can i treat my lawn now to address these issues? should i wait til another time? if so when?

District of Columbia County District of Columbia

1 Response

The least toxic controls are hand pulling and using weeding tools. There are a number of organic and less toxic controls on the market. These active ingredients include Acetic acid (vinegar), cinnamon oil, iron chelate, potassium salts of fatty acid, citric acid, and clove oil. These are non selective, contact herbicides. They are NOT effective on mature or perennial weeds that have a substantial root system. If you decide to use, follow label directions.

See our website for information and control of crabgrass including preemergents and tips for application http://extension.umd.edu/hgic/crabgrass
Click on the link for 'organic control' and corn gluten. It is not as effective as traditional herbicides and is a nitrogen source. Applying it at the recommended amount to control weeds may exceed the amount of nitrogen as recommended by the Fertilizer Use Act of 2011. Check the label.
Fertilizer Use Act of 2011.

The most difficult aspect of a more natural or organic approach to lawn care is controlling weeds. You will have to be prepared to tolerate some weeds for organic controls.
Basically some organic lawn care practices include a testing your soil every 3-4 years for pH, liming, and nutrient deficiencies; type of grass seed to sow; overseeding & renovation; mowing at the proper height; leaving the grass clippings on the lawn after mowing; and fertilizing in the fall for cool season grasses. (You should be aware that Maryland now has a lawn fertilizer law. This also applies to commercial companies too http://mda.maryland.gov/resource_conservation/Documents/fertilizerwebpage.pdf
http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG112_Turfgrass_Main...

mh