Winter Lawn Weed Control
The time to get ahead of winter lawn weeds is actually in the fall, but what you learn about winter weed control can also be applied to spring and summer weed control.
Start with Quality Care
If your lawn is healthy, lush, and thick, it will outcompete many weeds with which you might have problems. Any time there are disease or insect issues that open up a patch of bare ground within the lawn, weeds have the chance to establish themselves. So, water in the amounts necessary for your lawn, throughout the summer (and the winter if it is warm and dry), fertilize according to your turf type, mow at the highest setting for your type of lawn grass, and avoid walking or driving on the lawn when it is wet (which causes compaction).
Being on a lawn care routine will get you 90% of the way toward dealing with lawn problems.
Use a Pre-Emergent Treatment
To stop weeds from sprouting from seed, you need to inhibit their growth with a pre-emergent herbicide treatment. There are organic options (corn gluten) and synthetic options (various brand names) for pre-emergent treatment. This has to be spread on the lawn in advance of the change of seasons. That means August-September for winter weeds and February-March for summer weeds. If you have heavy rains, you might consider re-applying three months into the season.
These treatments will not stop weeds that sprout from perennial roots from sprouting. Those will have to be dealt with in a different way.
Stay on top of the Problem
You can hit winter weeds in warmer areas with specific systemic herbicides on days when the temperature is above 60 degrees. The weeds have to be actively growing for these systemics to work, but that is the only way to kill weeds that are perennials.
You can use systemic or contact herbicides for weeds that spread by seed. To achieve the best control, you need to spray the weeds or mow the weeds frequently before the weeds go to flower and set seed. Once the seeds have spread in the wind, your job of weed control is much more difficult.
For large weeds such as dandelions and thistles, the easiest and most fool-proof way to get rid of them is to dig them out so you can remove the entire long and large taproot that keeps the weed going. You can try weed killers, but it often takes four or more applications to kill those tough weeds.
You can keep winter, summer, and spring weeds out of your lawn. The key is vigilance. The smaller they are, the easier it is to eliminate them via hand-digging or chemical methods.