Mowing height helps rid lawn of grubs

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I worry about grubs destroying my lawn but I worry even more about using all these pesticides.  I think that there are life-forms that might be affected by these chemicals.  Is there any way to organically kill them?

You mean, other than harpooning them individually with a cocktail fork?

There now is a way but it isn’t really organic.  It’s more of a lawn management change.

There is new research this spring from Michigan State University’s Dr. David Smitley who is an entomologist that has done a great deal of work on Japanese beetle control.  He has determined that the way to prevent or really limit grubs damaging grass is to change your mowing height.  Raise your finished mowing height to at least 3-1/2 inches.  That’s the height of your grass when you finish mowing, not when you start.  You still will be doing the same good-grass-owner things like fertilizing occasionally and watering when it is dry.

His research has shown that healthy grass that has more length of blades to make food can repair grub root munching.  We have always known that the length of the grass blade determined how healthy the grass could be.

Like all plants, grass makes its own food through photosynthesis.  So technically, fertilizer isn’t “plant food.”  Fertilizer provides nutrients so the plants have the raw materials to grow and make more food for themselves.  The message has been to mow to 3 inches high. Now, the bar is raised to at least 3-1/2 inches if grubs are a concern.

To check your mower height, park the mower on a solid, flat surface. With the mower not running, measure from the ground up to the blade.  Don’t measure to the housing on the outside because the mower blade may not be even with the bottom of the housing.  Then, be sure to adjust all the wheels. Be sure that mower blades are replaced or sharpened at least once a year.

Grass can look really awful if it is being clubbed off rather than cut off.


I tried growing cauliflower last year in my garden.  It tasted good but was this weird yellow-brown color.  Is it the soil?

It has nothing to do with the soil and everything to do with how you handled the plants.  White cauliflower heads are created by pulling the surrounding leaves over them and rubber-banding them together over the head or ‘curd.”  This is done as soon as you see the forming head.  The sunlight shining on the white cauliflower turns it yellow-brown.  It may also make it bitter.

We have grown up expecting pristine white because those heads had leaves shielding them from the sun in commercial fields.  The process of pulling leaves over the forming head is called blanching.  The rubber band works well because it has a bit of give as the head and leaves grow bigger.  Just don’t put the rubber band on too tight.

Or if this sounds like a pain in your cauliflower, buy seeds or transplants for one of the colored varieties.  There are purple, orange and green varieties that don’t need to be blanched.  An orange variety is called ‘Cheddar’ and purple cauliflower varieties like ‘Purple Cape’ and ‘Graffiti.’ The yellow-green variety that grows into a pointed spiral is called ‘Romanesque’ or ‘Romanesco.’ Genetically, there is almost no difference between broccoli and cauliflower. ‘Romanesque’ and is also listed by the broccoli folks as being broccoli.

A green cauliflower by any other name tastes about the same.

Contact Gretchen Voyle, MSU Extension-Livingston County Horticulture Educator, at (517) 546-3950.


About Gretchen Voyle 51 Articles
Gretchen Voyle is the MSU Extension-Livingston County Horticulture Educator. She can be reached at (517) 546-3950.