Mulch costs less upfront and is better for plant health. Rock lasts indefinitely and requires less ongoing maintenance. The right choice depends on your climate, plants, and how much upkeep you want. Here's the full comparison.
Short answer: Use mulch around plants, trees, and garden beds where you want to improve soil. Use rock for pathways, borders, dry creek beds, and low-maintenance areas without plants. Many yards use both.
| Factor | Mulch | Rock/Gravel |
|---|---|---|
| Cost (per cu yd) | $25–$60 | $40–$100 |
| Cost to cover 100 sq ft (3" deep) | $25–$55 | $50–$100 |
| Lifespan | 1–3 years (decomposes) | Essentially permanent |
| Maintenance | Refresh annually | Occasional weeding, leaf removal |
| Moisture retention | Excellent — reduces watering | Poor — can increase soil drying |
| Soil health | Improves as it decomposes | No benefit — can overheat soil |
| Weed control | Good (3" layer) | Good (with landscape fabric) |
| Heat absorption | Insulates, keeps soil cool | Absorbs and radiates heat |
| Appearance | Natural, warm — fades over time | Clean, permanent — many styles |
| Wind/erosion | Light varieties can blow away | Stays in place |
| Material | Year 1 | 5-Yr Total |
|---|---|---|
| Mulch | $35–$55 | $175–$275 |
| Rock | $75–$130 | $75–$130 |
Rock is cheaper long-term despite the higher upfront cost.
| Application | Recommended |
|---|---|
| Flower beds & gardens | Mulch |
| Around trees | Mulch |
| Vegetable gardens | Mulch |
| Pathways & walkways | Rock/gravel |
| Dry creek beds | Rock |
| Foundation borders | Either |
| Slopes and hillsides | Rock |
| Xeriscape/drought areas | Rock |
| Play areas | Mulch (rubber or wood) |
| Fire-prone areas | Rock |
| Type | Cost/Cu Yd |
|---|---|
| Hardwood shredded | $25–$40 |
| Pine bark nuggets | $30–$45 |
| Pine straw | $20–$35 |
| Cedar | $35–$55 |
| Rubber (recycled) | $80–$120 |
| Dyed (red, black, brown) | $30–$50 |
| Type | Cost/Cu Yd |
|---|---|
| Pea gravel | $40–$65 |
| River rock | $50–$100 |
| Crushed granite | $40–$70 |
| Lava rock | $50–$90 |
| White marble chips | $60–$120 |
| Slate chips | $60–$100 |
Calculate rock/gravel quantities with our Gravel Calculator.
Mulch. It retains moisture, keeps roots cool, suppresses weeds, and improves soil as it decomposes. Rock heats up soil and provides no nutrition.
2–3 inches for both. More than 4" of mulch can suffocate roots. Rock: 2–3" decorative, 3–4" for pathways. Keep both away from plant stems and tree trunks.
Depends on market. In arid climates (Arizona, Nevada), rock is expected. In lush green markets (Northeast, Pacific NW), excessive rock looks barren. A mix usually appeals widest.
Neither recommended. Rock over mulch becomes a mess as mulch decomposes. Mulch over rock wastes material. Remove one before adding the other.
Every 1–2 years. Don't remove old mulch — add 1–2" on top to bring back to 3". Cedar and pine bark last 2–3 years.
Overall yes — no annual replacement. But rock still needs leaf removal (harder than off mulch), occasional weeding, and raking. Neither is zero-maintenance.