Dandelion Control

 

Kari Lewis, MSU Extension - Glacier County

It seems it’s the year for dandelions this year!

Dandelions are actually a perennial weed, and if not controlled, each plant's crown and root system will remain alive after the leaves have died in fall. Plants overwinter and begin growing again in early spring. Dandelions blooming in early spring do not result from newly germinated seedlings; but instead they are the result of the previous year's overwintered plants.  Therefore, the ideal time to control the dandelion, since it’s a perennial weed, is the fall.  However, bloom time in early spring, such as now, is the second best of the year for control.  Spring herbicide applications result in a slightly lower rate of kill than fall applications, but they are still worthwhile.

So, for removing those dandelions, there’s a couple options, either hand pulling or herbicide treatment.  If removing the dandelions by hand, you need to make sure to remove the whole root, rather than simply hoe off the top growth.  Any portion of the root left in the ground can sprout at least one new plant.  This mechanical removal is most easily done if the ground is moist, so be sure to get out there soon after a rain for hand pulling.

If there’s too many to hand pull, proper chemical treatment provides effective control.  A reminder that glyphosate (Roundup) is a non-selective herbicide, so will also kill the grass in your lawn.  Instead, 2,4-D is the best choice for dandelion control in lawns, as it only kills the broadleaf type plants, such as dandelion, not the grass.

If you do choose chemical control for your dandelions, here are a few guidelines

·         If there’s only a few weeds, simply spot spray the herbicide.  Apply just enough to wet the leaf and do not apply to the point that the herbicide is dripping off the leaf.

·         Apply the chemical to growing, preferably young weeds.  Don’t apply when the soil moisture is low and weeds are drought-stressed, as the control won’t be as effective.

·         Apply herbicides on a calm, clear day, when temperatures are between 50 and 85 degrees F.  Applying herbicides when the temperatures is over 90 degrees increases the potential for volatilization injury to other plants in the landscape.

·         Don’t apply if rainfall will occur within 24 hours, and avoid applying irrigation to the area for at least 24 hours following an herbicide application as well.  This is so the herbicide isn’t washed off the plant’s foliage.

·         Don’t mow the lawn for 2 days before or after the herbicide application.  This allows sufficient time for the herbicide to be translocated to the plant’s roots. 

 

As always, read and follow the label directions.  When making liquid herbicide applications, keep children and pets off the lawn until the product has dried or as specified by the label.