Dimension Failed

[Jed1]

Background: my three year old lawn is in marginal soil with pure sand underneath. The grass is Kentucky Blue and red fescue. With fertilizing and irrigation, it's FINALLY starting to fill-in. It's been a cool but dry summer here in SE Wisconsin. I mow 3" high.

I decided to try a professional service this year, and they applied Dimension last spring. This was the first use of a pre-emergent since it was the first year I didn't have to seed the lawn. Unfortunately, the crab grass development in the past three weeks has been pretty bad. I thought Dimension was rated to work all summer. Is this known to happen with Dimension or did the company do a poor job of application?

Thanks.

[greendoctor]

This is known to happen with all lawn care applications if there is no irrigation or rainfall occurring within a week or so. Dimension and other similar herbicides do not work if there is no water to distribute the product in the top layer of the soil.

[Jed1]

This is known to happen with all lawn care applications if there is no irrigation or rainfall occurring within a week or so. Dimension and other similar herbicides do not work if there is no water to distribute the product in the top layer of the soil.

That fits what happened. We didn't get any rain and the in-ground system wasn't operational at the time.

[greendoctor]

The product labeling for Dimension does mention that it is not effective for prevention of weed germination unless there is 1/2" of water be it rain or irrigation after application.

[DiyDave]

Sandy ground also is part of the problem, It says on most Pre-M pesticide labels to up the rate a little in sandy ground. Also, any kind of organic matter you can add to the lawn will help the situation. (compro, humus leaf mold, manure, compost, etc):waving:

[Jed1]

Sandy ground also is part of the problem, It says on most Pre-M pesticide labels to up the rate a little in sandy ground. Also, any kind of organic matter you can add to the lawn will help the situation. (compro, humus leaf mold, manure, compost, etc):waving:

Since I didn't apply it, I don't know if the contractor increased the rate. He didn't say anything about watering in lieu of rain; wish he had.

Compro looks like a good product, but isn't sold here. I did spread Milorganite in late June to boost the nitrogen and also add iron, which I was told is a good idea with the sand. It really did green it up.

Any thoughts about adding peat moss?

[DiyDave]

That'd work, too, just keep an eye on pH, if you add a lot of any one product.:waving:

[LawnTamer]

I work in a desert, so sandy soil is common, dimension sucks in sandy soil, I get very poor results, the best product I have found for sandy soil is Prodiamine, which is marketed under the names Barricade, Stonewall and a few other names, at it's high rate it really will work for 180 days.