The yellow flowers of spring are here and many more are coming, said Paul O. Johnson, SDSU Extension Weed Science Extension Associate.
 
"Although dandelions are running a couple of weeks behind normal in the state, they are here now, and if you did not get your yard sprayed last fall, expect to see them in your yard throughout the summer," Johnson said of the weed which thrives on cool damp weather.
 
He explained that the dandelion is a perennial that can produce multiple flowers. "With a large plant more than 50 flowers have been found to be produced with 50-150 seeds per flower," he said.
 
Johnson added that spring treatments are not as effective as fall but can be used to stop the yellow flowers from producing viable seed.
 

How to treat

Herbicide treatments: These can be used either as a weed-and-feed type granule or as a liquid spray. The chemicals must enter though the leaves. Spray products can be applied with a variety of equipment. "Keep sprays coarse and use low pressure to reduce the chance of spray going on non-target sensitive plants. Remember the more mature the dandelion the harder it will be to kill," Johnson said.
 
Dig: Scattered plants can be dug, but be sure to cut the root off below the ground so the crown is killed to avoid the plant coming back as a new plant.
 
Fall treatment: This fall, make a note on your calendar to control dandelion after the first frost. "You do not need to be one of the people with a yellow lawn next spring. Remember even if your lawn looks good this year, seedlings can be back next year," he said.
 

source: iGrow.org