- Define the flower bed edge - Use marking paint to lay out the shape of the flower bed. Once the edge is defined,use a shovel or rent a commercial bed edger to dig an area 2-4" deep along the perimeter of the bed. This helps hold the mulch in place and stops it from ending up in your grass.
- Prep the bed - Clear any unwanted vegetation from the flower bed area. Spray a pre-emergent herbicide anywhere you do not want vegetation to grow to inhibit the growth of weeds in the future. This step is important because mulch itself will not kill existing vegetation.
- Install 3-4" of mulch - When establishing a new mulch bed, 3-4" of mulch is needed to create a thick enough barrier to prevent weed growth. Try not go install any more than 4" or else it may promote mold.
- Add more annually - Each year, add 1-2" of mulch on top of the existing mulch. Over the course of the season, the wooden mulch will decay directly into the soil requiring annual replenishment to prevent weeds.
"Wait... Don't I need to install a weed barrier first?"
In my opinion, no... Weed barriers are great for a little while. After a year or two, the mulch installed on top decays onto the top of the barrier. This creates a spot for weeds to take hold - right on top of the weed barrier. Basically, a weed barrier leads to a large project every few years when it all needs to be torn out to start fresh.