Since Acetic Acid (vinigar) is a stable compound, It will take a long time for the acid to degrade.

However, how it affects the pH will depend on the structure of the soil. It you have a lot of carbonates in the soil pH wise it will have little effects. If you have a soil made up of little basic components mostly organic and silica, it could have a long term effect.

Vinegar weed killer is applied as a foliar mist, not a soil drench. It should have zero effect on the soil pH. Even if it was applied as a soil drench, vinegar is a carbohydrate which is immediately picked up by soil bacteria as food. And if you have any lime already in your soil, vinegar would convert to carbonic acid which is exactly what plants use to convert minerals to useful plant food.

But I can almost guarantee you that vinegar will have no long term effect on creeping charlie. If it were that easy, everyone would be doing it. Instead they are using RoundUp and reapplying at least 2 more times to finally get rid of the charlie. CC develops a very dense mat of roots under the soil which seems to help prevent new plants (like grass) from growing. Once you get the plant killed, then those roots become organic matter in your soil and the soil microbes will decompose them. But killing it completely dead is the hard part.

If you have long term success with vinegar, please write back with details of your approach and strength of the vinegar, etc. The world is anxious to have a reliable way to get rid of this monster weed.

As for overseeding, assuming you applied the vinegar as a foliar mist, then seeding anytime after the weed is really dead should be no problem. I would water it lightly 2x per day for a few days to see if the charlie springs back.

This post was edited by dchall_san_antonio on Fri, Sep 13, 13 at 16:37