We got a lot of rain this last winter & spring, and the weeds are out in full force. I'm thinking I would be better off if I were to spray some weedkiller that will last at least a full year, if not longer.

(1) Do any of you have experience with this--did it really keep the weeds away, and for as long as the label said it would?

(2) If this stuff works, is there any product that is better than the rest, or are they all pretty much equal?

(3) Finally, does this stuff kill the weeds that are already there, or does it just prevent new growth?

 

I'm not the pro here just a homeowner.

A weedkiller that strong would not only kill the weeds but almost everything else that is trying to grow. You need to strike a balance between application and effect.

 

This would be applied where the only things we want to keep growing are trees. There is one small section that also has flowers we want to keep, but that's it. I suppose I'd need to read the directions on this product, before applying it close to them (to see how far away I would have to apply it).

 

Sure, they have such a thing. My old neighbor used to work for ADOT and asked what they used along side roads and overpasses. Bought some very similar for consumer use and was told it was very close in action and application. He put it down in an area beside his house that was a little hard to access and he didn't want to mess with it. Full strength, just hook up a hose IIRC. He said he was happy with the approx 300 sf coverage and the results. He must have a darn good pension since it was $75 a gallon!

I'll stick with what I get at Wally World (Spectracide?) and do it 3 times a year or so. $20 covers my whole lot 3 times over. Kills everything, not just weeds.

 

There are herbicides with long lingering capability. You apply them once and they continue working for many months. Unfortunately they have a huge drawback. They do not bind with the soil so rain and water can move the herbicide. If you have a heavy rain it can wash the herbicide to a different location. So you could end up with weeds growing back where you treated and have dead streaks where the rainwater washed off the herbicide. So, you need to be very mindful where you apply it and where it will wash off.

Herbicides containing glyphosate (Roundup, Honcho, Glyfos...) kill plants by being absorbed through the green leafy material. Any of the herbicide that contacts the ground readily binds with clay in the soil and does not move. So, a couple hours after application enough has been absorbed into the plant to kill it and if it rains once the herbicide hits the ground it's pretty much stuck in place and doesn't wash away creating dead streaks.