Preen products contain a pre-emergent herbicide. In layman's terms, it keeps seeds from germinating -- and that's how it keeps beds weed-free. It won't kill existing weeds but will keep new weed seeds from germinating. Keep in mind that it actually prevents ANY seed from germinating, so if you have beds with self-seeding annuals, you will keep those seeds from germinating as well. If the only annuals you grow are those you put in as plants (either purchased as such, or grown from seed in trays to be transplanted into the beds), then you're fine.

I don't think the products are necessarily bad, but I wouldn't use them because I like the idea of self-seeding annuals (they'll be the icing on the cake after I get the roses and perennials planted). If that's not an issue for you, then ignore my warning.

:-)

~Christopher

That's why I wouldn't use it. I don't know what I would do w/o my self-seeding plants to fill in the empty spots.