I have a viney weed growing in my yard. Weed and Feed doesn't seem to affect it. It's slowly spreading to more and more of my yard every year. What is it, and how do I kill it?
For killing weeds in an established lawn, a Weed Spray is usually the easiest way. A weed spray kills weeds without harming grass (provided the grass is healthy).
I've had good luck with Spectracide, but the Ortho product mentioned in here works well too. The Spectracide label says it kills Ground Ivy, so it should work on your weed.
Note that a targeted weed spray is a different than a general purpose herbicide like RoundUp. Don't get them confused, or you will have a dead lawn. Read the label! If you are really cautious, look up the active ingredients and see what they do (Google them).
If you have a lot of spraying to do, consider buying a Pump Sprayer. The squeeze trigger bottles will cramp your hand if you have a lot of spraying to do. You can also re-use the pump sprayer for other things like bug spray and deck cleaner.
Big established weeds will take a long time to die. It will probably also require multiple applications of the spray (spaced several weeks apart, read the label). Try plucking/cutting the Ivy so the spray doesn't have as much work to do.
If you get "holes" in the weeds (e.g. by ripping pieces off), you get an entry point for the spray into the plant's "bloodstream".
After the weeds are dead, you may have bare spots in your yard where they were growing (or just big chunks of dead ivy.) You may need to re-seed those spots, but wait a while. The weed spray can interfere with new grass. It's also best to plant grass in the fall anyway.
Weed and Feed products and weed preventers like Preen are usually pre-emergent, meaning they don't kill stuff that is already growing (check the label). That's why you usually only apply them early in the year, before the weeds can germinate. The Sprectracide spray I suggested also contains a pre-emergent weed preventer (not sure about Ortho).
To make life easier in the future, try to stop the weeds before they get too big. Use a weed preventer, and spray/pluck them early.
I suspect most weed and feed products will be pre-emergents, meaning you need to get it in your lawn before the weed seeds have a chance to germinate, which is a limited window. Once something like this is already growing, you're usually left with the round-up type of products, which kill everything they touch, or hand pulling.
After a long day in the office, sitting outside on a nice day, pulling weeds, can be therapeutic. Just make sure you get as many of the roots as possible. And with viney or runner spreading weeds, try to get the entire runner.
I have had some pretty good success with Ortho Weed-B-Gon Max. I have used it on crabgrass, clover, and wild onion and it does a pretty good job. Pretty much I have used it for spot treatment in small areas but you can also use it with a sprayer to spray a larger area.
Don't kill it, just learn to live with it and look how beautiful it is. If ever it takes too much space, reduce it mechanically by hand. Remember that plants are very strong and that products which are able to kill them hurt you also...
You will save money, and learn more interesting things by tolerating wild flora in your garden! In fact you are lucky that they are willing to come!
This Henbit loves moisture. Although prolific it would not stand a chance if you would train your grass to have deep roots. You've been watering too little too often. This technique makes for shallow rooted grass. These cool season grasses have huge root systems, genetically. They appreciate being trained by allowing the soil to dry out before watering again. Water deeply and do not water again until you see your footprints stay down in the grass.
Watering deeply and allowing the soil to dry saves water, your lawn will be healthier and drought tolerant and Henbit will not be happy. You need a broadleaf herbicide designed for lawns. Weed and feed is always one of this type of weedkiller.
The trick is to wet your lawn down first and apply the herbicide (granular form) using a rotary spreader. The water will help the broadleafed weeds to hold onto the herbicide. You can purchase just the broadleaf weed lawn killer without the fertilizer. Don't water or mow for a couple of days.
Mow your grass on high at the very least 3" no shorter. Have you aerated this year? Look up questions on lawn care maintenance for cool season grasses on this site. There are some hard and fast rules for cool season lawns that if followed you'll never have to use an herbicide again. Also check the pH of your lawn. Ideally 6.5 to 7.0. Henbit likes more acidic soil. Again, just the management of your lawn will help the grass itself to outcompete, shade out germination of weed seeds, and you will be selecting for your grass and discouraging weeds.