Hi Ginny,

Unfortunately, no mulch or ground cover will 100% prevent weeds. So your options are to: mechanically remove the weeds (pull or hoe), use herbicides, or increase plant habitat to better cover the breeze and prevent fewer chances for weeds to grow.

If these are paths, your options are to either pull/hoe the weeds or use herbicides (since you don't want to plant in the middle of your paths). Many weeds germinate from the surface of mulch, not from the soil.

To confirm, this is the small rock pathway material? If so, you can buy it at landscape supply companies, like Site One, Crystal Landscaping, etc.

Hi Ginny,

Thanks for the photo. Yes, I've heard of breeze and it's most commonly used for pathways because it packs down and makes a smoother surface. I haven't often seen it used as mulch, but it could work.

Because you don't have many/any plants in this area, you can use herbicides to control the weeds. Any burn-down product (nonselective) herbicide will work, including glyphosate, horticulture vinegar, iron, fatty acids, etc. Or, as I mentioned previously, introduce additional plants as competition, such as perennials or ground covers. Nature will want to plant weeds in any desirable surface, so competition is important.

With your aspen, where is the root ball? Is it planted at the grade of the breeze? Is the potting media on top, in the concrete blocks, covering the root ball?

Thanks for the clarification. For the overall health of the tree, remove the soil on top of the root ball. Studies have been done where the top of the root ball doesn't actually lose that much moisture - and burying it can be far more harmful than beneficial. 

Instead, focus on routine watering while the tree gets established - you can follow these guidelines: https://extension.umn.edu/planting-and-growing-guides/watering-newly-planted-trees-and-shrubs