OOps- I meant to say I used to apply Preen in March and Sept- not March and May.

Karen

I have the same problem in my perennial beds and find if I deadhead the worst of the seeding perennials it keeps it almost under control. I think also using cardboard under the mulch would help and I might do that this year.

Don't know about Preen, but my DH will again be using roundup on our driveway. He hasn't used it for a few years because I'd like to be completely organic here but the driveway is quite weedy. Doesn't bother me but it does bother him as he has to mow it and it's 500' long.

After reading about corn gluten meal I've decided against it, not enough positive reports.

I couldn't do cardboard- I have lots of perennials already planted and I stuff annuals in between. I like full flower beds. And those !@#$%^& birch trees pop up everywhere, even within the confines of established perennials.

I sure would like to kill my neighbor's birch. It is pretty, and the biggest I've ever seen. They tell me it has exceeded it's life expectancy, 30 some years old now. It is huge.

A little Preen would go a long way to improve my gardening experience...

Karen

I tried earler to open the msds sheet. I was unable to but then I was on the virus-infected computer. I'm on my husband's laptop now and I'm able to open it.

Let me restate- is there any pre-emergent that isn't toxic and does work?

Karen

What type of mulch do you use and how thick are you applying it?

I use lots of mulch... of course I still get weeds, but certainly not thousands. And usually weeds are easy to pull in a thick mulched bed... except for Maple trees.. those buggers are hard. I clip them off with my pruners. After several clippings they don't come back any more.

Believe me, those maples are nothing compared to birch. My next door neighbor's maple is blowing whirlybirds all over my back yard now. Don't know what kind of maple it is but it's more upright (taller and skinnier) than my sugar maple and it's whirlybirds are red.

I mulch with about 3 inches of wood bark mulch in spring or early summer. By the next spring, it's gone, consumed.

In fall I apply about 2 to 3 inches of shredded leaves (but with the leaves come more volunteer trees). Much (most) of that is blown away during winter. The leaves are shredded and I wet them as soon as I put them down, a little sprinkle of soil on top. Still, they blow away. My neighborhood sits on top of a BIG hill right on the Ohio River. (I can't tell you how many roof repairs/replacements we've had in 26 years.)

Karen

I'm curious about Preen myself. The wife bought some, put it on a flower bed, and killed the flowers. I'm not sure how it's supposed to be able to tell the difference between flowers and weeds. Can you only put it around things you want to kill, like Roundup?

Preen isn't supposed to kill live plants - it prevents seeds from germinating. So if you have an established perennial bed, preen minimizes sprouting of new plants... like weeds.

My neighbor uses Preen... it only took me a couple years to figure out why this one area of my yard never reseeded...

I killed off a section of lawn on the south side of my house and reseeded it with a butterfly mix. There is this one strip right along the landscape border that divides our property line that is completely bare... no plants, not even weeds... I finally figured out their Preen is running off the bed and down the edge of that landscape border. So now if I want something to grow there, I'm going to have to put plugs in, not seeds.

Here's the msds.

But they make a lot of different products, including brush and week killer. Could your wife have used that by mistake?

Karen

Here is a link that might be useful: MSDS

Many people have a problem with the Corn Gluten Meal because they do not follow the directions for its use and they expect too much from it after one application. Read what the researchers at Iowa State University have to say about how and when to spread the stuff.

Here is a link that might be useful: Corn Gluten Meal Iowa State

It was said: "I'm curious about Preen myself. The wife bought some, put it on a flower bed, and killed the flowers."

Timing is the key. Contrary to what it looks like on the commercials, you can't plant & use Preen the same or next day, then expect the plantings to survive. The label says something to the effect of "after established" -- in other words, several weeks post-plant.

I think it was bedding plants that were fairly small, or else they died from some other cause. It was a couple years ago so I don't remember very well.

Thanks for clarifying how Preen works though.