Sure, here are some easy and affordable rock landscaping ideas for your backyard:

Rock Garden: Create a small rock garden by arranging different sizes and shapes of rocks. Add some drought-resistant plants like succulents or ornamental grasses among the rocks for a low-maintenance and visually appealing display.

Dry River Bed: Mimic the look of a natural river bed by arranging river rocks or larger stones in a winding pattern through your yard. This can help with drainage and erosion control while adding visual interest.

Rock Pathway: Lay down a pathway of flat stones or gravel bordered by rocks. This can create a charming walkway through your garden or yard and is relatively easy to install.

Rock Border: Use rocks to create borders around flower beds, trees, or other landscaping features. This adds definition to your garden beds and helps to prevent soil erosion.

Rock Mulch: Instead of traditional organic mulch, consider using rocks or gravel to cover the soil in your garden beds. This can help retain moisture, suppress weeds, and add a decorative element to your landscaping.

Rock Retaining Wall: If you have a sloped yard, consider building a rock retaining wall to create terraced levels. This can help prevent erosion and create usable space for gardening or seating areas.

Rock Sculptures: Get creative and use rocks of varying sizes to create sculptures or focal points in your yard. This could be anything from a stacked rock tower to a whimsical rock animal.

Rock Fountain: If you're feeling ambitious, consider installing a rock fountain as a centerpiece for your backyard. You can either purchase a pre-made fountain or build one yourself using rocks and a recirculating pump.

Remember to consider the size, shape, and color of the rocks you choose to ensure they complement your existing landscaping and create the desired aesthetic. Additionally, try to source rocks locally to save on costs and reduce environmental impact. With a little creativity and effort, you can transform your backyard with beautiful and affordable rock landscaping features.