Getting to the Root Cause of Weed Problems

I am most often asked, “What do I need to kill nutsedge?”

To answer this, I first ask about the site conditions. Is it very wet from poor drainage or excessive irrigation? Is there compacted soil or signs of stress from other plants?

Most weeds are indicators of larger problems in the landscape. This doesn’t mean that if you fix the condition the weeds go away, but it will make controlling them easier.

Here are a few weeds and what they might mean:

• Nutsedge is an indicator of wet soil. Reduce the amount of water in that area—install a drainage system or adjust the sprinkler system, if applicable—and the sedge will find it harder to live in that environment.
• Moss is an indication of acidic soil that may need an application of lime. It’s also a sign of excessive moisture.
• Sandbur grows in dry soils.
• Plantain grows in compacted soil.
• Chickweed can indicate alkaline soil that needs an application of a soil acidifier like ammonium sulfate.

Only a soil test will confirm the actual soil conditions and there will be some exceptions to the “rules,” but large populations of a weed can tell you something about your growing conditions and should clue you in to what your problems are.

Pay attention to the weeds and what conditions they are growing in and it will help you improve the landscape using fewer chemicals.