Sudden influx of dandelions throughout Colorado have likely been growing for years

From the Denver metro area to northern Colorado, many people in Colorado have been complaining about the number of dandelions springing up in yards and parks in recent weeks. Researchers with Colorado State University say the relatively dry spring Colorado has experienced before recent weeks allowed the weeds to grow much easier than the lawns and fields they are thriving in.  

"They tend to distract from the uniformity of a nice green lawn," said Tony Koski, professor and turf expert from Colorado State University. "It is a short window of flowering, but they are in your face." 

Many may think the week of rain Colorado's Front Range recently experienced lead up to the surge of dandelions. However, it was the dry weeks prior that kept the grass around the dandelions dead while the weeds grew due to their ability to absorb and store water from months ago.  

"One thing to notice about dandelions is they have a very thick root system that holds a lot of water, that is why they have done really well early in our year when it was dry," Koski said. "They didn't care if it rained or if you watered your grass, because they have water stored in those roots from last year." 

Most of the dandelions we see in our yards are not native to Colorado, but rather Europe. Koski said that, in part, is why they thrive so much in Colorado. However, he said the significant amount of weeds we are seeing in many parks and yards right now is partially a result of failing to do routine treatment to kill them years ago.  

"Most of the ones we see flowering now are two or three or four years old," Koski said.

While the fall months are said to be the best time to treat your lawn for the weeds, there are products you can purchase to kill the weeds now.

While many kids enjoy playing with the dandelions, sometimes blowing the white "fuzz" off of the top of them, those are seeds that then go on to make even more dandelions.

"Each plant can have 5,000 to 10,000 potential dandelions floating around from those seeds," Koski said.

Koski says the key is making sure your lawn has few visible patches of soil which can be prime territory for these pests. 

"The best defense against dandelions or any weed is have really healthy grass," Koski said. 

It should be noted that dandelions can be a great thing, depending on who or what is seeing them. Dandelions are great for pollinators. And some people even eat them in salads before they turn bitter as they grow.