How to Spray Bleach on Thistle Heads


Thistles, which are considered weeds, spread quickly and use up valuable nutrients in the lawn or garden. Canada, bull, milk, tall and musk are just a few thistle varieties that grow across the U.S. All thistles are tall, spiny plants that are typically killed with a commercial herbicide, such as one that contains 2,4-D or glyphosate. As a cheaper alternative, you can use bleach to kill your thistles since bleach kills any vegetation it comes in contact with.

Step 1

Mix equal amounts of chlorine bleach and water into a spray bottle. For fewer spills, use a funnel to transfer the bleach to the spray bottle.

Step 2

Spray the thistle heads, and work your way down to the roots. Do not get the bleach mixture on your grass, plants or other vegetation in the area; however, if you accidentally do, immediately wash it off with a hose, or wipe it off with a damp rag or sponge.

Step 3

Reapply as necessary, such as when you see new thistles emerge. Use straight chlorine bleach if the treated thistles do not die within a week.

Tips and Warnings

  • Avoid spraying too much bleach so that it drips to the ground. The sodium in bleach is harmful for lawn or garden soil. Use common sense when working with bleach. Work with it outdoors or in a well-ventilated room. Do not mix bleach with other chemicals, especially ammonia.

Things You'll Need

  • Bleach
  • Water
  • Funnel
  • Spray bottle
  • Rag
  • Sponge


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Keywords: spray bleach, thistle heads, kill thistles, control thistles, homemade weed killer

About this Author

Melissa Lewis has been a professional writer since 2005. Her work has appeared in various online publications. A former elementary classroom teacher and media specialist, Lewis is also a script writer, with a movie script, "Homecoming," she co-wrote currently in production. She holds a Bachelor of Arts in psychology.