Mulch Basics: Everything You Need to Know

Mulch gives gardens a polished look while conserving moisture, insulating roots from temperature extremes, and suppressing weeds. Here's your complete guide:

What Is Mulch?

Any material that protects the soil surface while allowing air and water penetration. Organic mulches (plant-derived) add nutrients and improve soil over time: compost, aged manure, leaves, pine needles, herbicide-free grass clippings. Inorganic options: gravel, granite, stone.

Common Questions

Will manure burn plants? Only if not well-composted. Look for "well-composted" on labels; ask bulk suppliers.

How much to buy? 2-cu-ft bag covers 8 sq ft at 3 in. depth; 1 cu yd covers 108 sq ft at 3 in.

How thick to apply? Denser materials need less depth.

Application tips? Keep mulch a few inches from trunks and plant crowns to prevent rot.

Keep it clean? Remove debris with a hand rake; blowers may displace light mulches.

When to mulch? Early spring before weeds sprout; optional second layer in late fall.

When to remove? Never—just pull aside for planting.

Container mulching? Same depth and technique as in-ground.

Six Favorite Mulches

• Straw: Light, loose; great for veggie/strawberry beds. Buy at feed stores. Avoid hay (seeds). Apply 4–5 in.
• Hazelnut hulls: Good general use; ideal for paths (water permeable, don't stick to shoes). Common in Willamette Valley. Apply 2–3 in.
• Cut bark: All-purpose; mini size looks polished. Small: 2–3 in.; large: 4–5 in.
• Decomposed granite: Compacts fast, resists blowing. Southwestern look; weed-prone. Apply 1–2 in.
• Shredded bark: Slow decomposition, natural look, knits together—good for slopes/windy areas. Apply 2 in.
• Tumbled glass: Pricey ($3–7/lb); adds color to small areas. Source: Bedrock Industries. Apply 2–3 in.