The Pros & Cons of Weed Blocks for Flower Beds

Established Beds

• If the plants in your flower bed are a mix of mature shrubs and perennials and you don't plan to introduce new plants or annuals, laying down cloth or permeable plastic weed block can reduce your weeding chores substantially. Cover the block with 2 to 3 inches of mulch, such as bark chips, wood chips or gravel. The downside of installing synthetic weed block in the bed is that you will need to cut it in pieces and overlap them to fit around the plants. You'll also need to slice holes in the block if you want to add plants. If you want bulbs in your bed, as most gardeners do, you won't want to lay weed block over them.

New Beds

• In beds where the plants are young, using synthetic weed block isn't a good idea because the plants need space at their base to expand as they grow. The best choice in this case is to lay a thick layer of newspaper (10 to 20 sheets) around the plants and cover it with mulch. The newspaper will decay over a year's time and won't inhibit the plants' growth. It's easy to add new plants to the beds through the newspaper, but you will probably get shreds of paper on top of your mulch and need to remulch to tidy up. If you are starting a new bed, it may seem as though laying landscape cloth and cutting slits in it for the plants will make your life easier. But that is true only if you plan never to change the plants' placement. If a plant dies or you change your mind about one, you will find that the cloth inhibits change.

Annual Beds

• If you plant a bed with annual plants each year, such as in a circle around a mature tree, weed block won't serve you well. In fact, any bed that undergoes plant or design changes isn't a good site for weed block, as you will need to keep lifting it off or cutting it up to accommodate new ideas. Instead, use a thick layer of organic mulch around the plants and renew it each year.

Benefits

• Reducing weed growth reduces competition for nutrients and water, and weed blocks do a good job. They also help conserve moisture by slowing evaporation. Mulch on top of newspaper is quickly broken down into nutrients for the plant by soil organisms, lessening the need for fertilizer. And, of course, the fewer weeds, the fewer you need to pull.