How Long Does Preen Last?

Preen^® Garden Weed Preventer works to create a barrier that inhibits weed seed growth. The barrier can last up to 12 weeks.

How long is Preen effective?

In the garden, Preen remains effective for up to three months for Preen Garden Weed Preventer and up to four months for Preen Weed Preventer for Southern Gardens. Preen weed preventers do not persist in the soil, nor will they leach into groundwater.

Can you use too much Preen?

Using too much of the product is just as wasteful and may be harmful to plants and the environment. That means you should identify what the problem is before applying a product. If you have bugs on a plant and apply a fungicide, you will still have bugs.