Preen Weed Preventer

Tue Jan 22, 2013 2:14 pm

I see a lot of ads for the Preen Weed Preventer, which is supposed to stops weed seeds from germinating, so I thought I would try it to keep the weeds down in my tomatoes since they are a little hard to hoe once I put cages around the plants. According to the label it is supposed to stop seeds from germinating for 60 days. It did work as advertised, but the next year I planted green beans in the same area, and where I had used the Preen they did not come up. Where the row went beyond the former tomato area all was normal, but in the area where the tomatoes with the Preen had been I got less than a 10% germination rate. Last summer i finally had good germination results in that area, so if you are thinking about using it, I suggest considering what will be there next year as well.

Re: Preen Weed Preventer

Tue Jan 22, 2013 2:23 pm

You have to be careful of the amount you put down and the time of the year.

Re: Preen Weed Preventer

Tue Jan 22, 2013 3:57 pm


What you are describing is consistent with over-application of the product. Applying herbicides is not a case of -- if a little bit is good, a lot is better. That is why knowing the actual square feet in the area to be treated and then measuring out the correct amount of product to apply to the area.

In my experience as County Extension Agent I've had to deal with lots of people that didn't read/ignored the product label and got into trouble. Read the label before applying the product not after.

Hope this helps.

Re: Preen Weed Preventer

Tue Jan 22, 2013 4:52 pm

My dad used to literally dump the preen on atleast once a month in his garden. He used it on the corn once it sprouted and around the taomatoes severly. I got on him really hard one day when he came home with 6 buckets of preen for the garden. I told him him those instances would happen and he would not listen to me at all till one day I showed him an article in my Landscaper's Journel Magazine about the over use of chemicals. Dad was getting so bad with it that I thought I could tell the effects of it in how the vegtables tasted. I brought him a Tomato out of a different garden and compared them and I could tell a difference. His was a little more Tart. If that is why I do not know, I am no way an expert gardener but I quickly saw something was going the wrong way.

I know some farmers are having problems with seed germination too because of the over use of weed chemicals. It will be a problem one day I believe?

My .02 worth, I can't wait for spring cause I sure do miss those Fresh Home Grown Vegtables.

Take care and enjoy.

Re: Preen Weed Preventer

Tue Jan 22, 2013 6:04 pm

It's the middle of January, 3 degrees here in Michigan and you're talking about gardening and tomatoes? I just got in from plowing snow. At least you're thinking about spring!! :lol:

Re: Preen Weed Preventer

Tue Jan 22, 2013 8:20 pm

If you have any pine trees in your area, the straw works great keeping the grass and weeds down after you have the basket(cage)around them.

Re: Preen Weed Preventer

Tue Jan 22, 2013 9:26 pm

Used it once in early summer, and a very light application. Don't think it was over application, but whether it was are not, I will not use it again. I use shredded paper from the city, and my own shredder for mulch now.

Re: Preen Weed Preventer

Wed Jan 23, 2013 11:46 am

John, I agree with you on the paper mulch. When I set out my tomatoes I take a sheet of newspaper and tear a hole in the middle. I slip this down over my young plant. Then jam my basket down thru the paper to help hold it in place. A little dirt on the outside edges also helps keep it in place. Not the pretties way to mulch but it sure helps keep the weeds from growing around your tomatoes. One added benefit is by season end the newspaper has mostly gone so there isn't any clean up for the next season.

Re: Preen Weed Preventer

Wed Jan 23, 2013 12:20 pm

We use several sheets of newspaper, then old straw as mulch. Does a great job.

Re: Preen Weed Preventer

Thu Jan 24, 2013 8:02 am

There are many different formulations under the Preen label. It's one of those over the counter herbicides that easily confuse the customer. Unless you do your homework it would be easy to buy a product that does not do what you think it should. One size does not fit all.

Re: Preen Weed Preventer

Sat Jan 26, 2013 2:00 pm

I have used Preen ever since it became avail. and also use other pre-emerge sprays in the middles of the rows!---I use the SAME hi-power stuff the commercial so called ORGANIC guys! (dont like it BUT cant grow stuff without it!)
Mulch here only invites bugs snails /voles/mice into the garden!---also makes a big slimey mess under the stuff, hard/cold/wet enviroment and the plants just die---Thats why I had to go the chem. routes here!---gotta use what works for you! I know what amount it takes too! (wont post that part)----these are all ORGANIC ingredients in these chems!---READ THE SHEETS!!!!! thanks; sonny

Re: Preen Weed Preventer

Sun Jan 27, 2013 7:58 am

I use Preen at prescribed rates on asparagus and still get weeds. On the garden I use a mulch with soaker hoses under it and it works ok. I have used newspaper and a thin layer of mulkch, grass clippings, I think paper w/o the clippings is a little ugly.. I have three acres out back so I can cut about all I want. Has anyone ever heard if soil type has any effect on Preen? I have a sandy loam and it doesn't work very well but my in-laws used it once on their garden and had carry-over? They have a clay soil. Vern

Re: Preen Weed Preventer

Sun Jan 27, 2013 10:07 am

I use a 144 cultivator for weed control.....

What is the active ingredient in Preen? I am thinking that soil type would definately affect how well it works. The label should give some directions related to that. If so, heavier, more organic soils would need a higher rate than sandy, mineral soils.

First law of pesticide use is know the pest. Second law is read and follow the label.


Re: Preen Weed Preventer

Sun Jan 27, 2013 11:28 am

I think we are talking herbicides here. Google Preen and read all the labels and MSDS's That should answer most of the questions.

Re: Preen Weed Preventer

Mon Jan 28, 2013 8:38 am

Super A wrote:
I use a 144 cultivator for weed control.....

Best weed control in the world…. And no carry over….