Premium Black Volcanic Cinder - Landscaping & Soil Mixes | Big Island

Black volcanic cinder (also called scoria) is a lightweight, porous volcanic rock formed
during volcanic eruptions. It's used for:

• Improving soil drainage and aeration
• Mixing with topsoil (ideal 50/50 ratio for gardens)
• Mulching and ground cover
• Preventing root rot in orchards
• Drainage layers in raised beds and grow beds
• French drains and erosion control
• Lightweight fill for landscaping projects

Black Cinder:

• pH neutral (6.5-7.5): won't change soil chemistry
• Lighter weight (30-40% less than red cinder)
• Maintains structure for 20+ years
• Minimal dust production
• Safe for all plants including acid-sensitive crops
• Higher initial cost but better long-term value

Red Cinder:

• More acidic: gradually lowers soil pH
• Heavier: harder to work with
• Breaks down into dust within 3-5 years
• Creates messy dust clouds
• Can stress sensitive plants with excess iron/boron
• Lower initial cost but needs replacement

Quick calculation

• 10x10 area at 3" deep = 1 cubic yard
• 10x20 area at 3" deep = 2 cubic yards
• Garden bed 100 sq ft at 4" deep = 1.25 cubic yards
• Drainage layer for raised bed (3" deep, 100 sq ft) = 1 cubic yard
• Call for free project calculation: 808-425-0474

Our black cinder is 1.5" minus, meaning it's screened to remove anything larger than 1.5 inches. This creates a varied size distribution from fine particles to 1.5" chunks—ideal for creating optimal pore space for both drainage and moisture retention when mixed with soil.

For Most Gardens & Vegetables: 50/50 mix (1 part black cinder + 1 part topsoil)

• Balanced drainage and nutrition
• Prevents compaction
• Retains adequate moisture

For Heavy Feeders (Tomatoes, Squash): 70/30 mix (70% topsoil + 30% black cinder)

• More nutrients available
• Still excellent drainage

For Orchards (Avocado, Citrus, Mango): 60/40 mix (60% topsoil + 40% black cinder)

• Maximum drainage for root health
• Prevents root rot in high-rainfall areas

For Raised Beds: Layer system

• Bottom 3": Pure black cinder (drainage layer)
• Top 8-12": 70/30 topsoil-cinder mix (growing medium)

Yes, black volcanic cinder is naturally pH neutral (6.5-7.5) and will NOT alter your soil's pH balance over time. This is a critical advantage over red cinder, which contains higher iron oxide levels that gradually acidify soil. Black cinder is safe for acid-sensitive crops and maintains optimal growing conditions indefinitely.

• Retail Price: $97 per cubic yard
• Minimum Order: 1 cubic yard
• Bulk Discounts: Available for 10+ cubic yards (call for pricing)
• Delivery: Included in price for most areas (call to confirm)

Compare to red cinder at $60-75/yard: Black cinder costs more upfront but lasts 3-4x longer, making it significantly cheaper over 10 years.

No. Volcanic cinder is permanent rock that will NOT break down, decompose, or degrade. This is a major advantage:

• One-time investment (no replacement needed)
• Drainage benefits last 20+ years
• Doesn't settle or compact like organic materials

No ongoing maintenance costs Red cinder, in contrast, breaks down into fine dust within 3-5 years and loses drainage benefits.

Yes! Black cinder makes excellent permanent mulch:

• Weed suppression: Blocks light to prevent weed germination
• Moisture retention: Reduces evaporation from soil surface
• No decomposition: Never needs replacement (unlike wood chips)
• Pest resistant: Won't attract termites or other insects
• Professional appearance: Dark color looks clean and attractive
• Temperature moderation: Insulates soil from temperature extremes

Apply 2-3" layer around plants, trees, and shrubs. Keep 2-3" away from plant stems.

Excellent for orchards, especially in Hawaii's high-rainfall climate:

Best for:

• Avocado (extremely sensitive to waterlogging)
• Citrus (needs good drainage)
• Mango (prone to root rot in wet soil)
• Macadamia nut trees
• Any tropical fruit trees

How to use:

• Mix 40% black cinder into planting hole backfill
• Create drainage layer below root zone
• Top-dress around mature trees (3-4" layer)
• Prevents root rot while maintaining moisture for fruit development

Both! Black cinder's porous structure:

• Drains excess water quickly through large pore spaces between particles
• Holds some moisture within the porous rocks themselves
• Releases moisture gradually as soil dries

This dual action makes it ideal for Hawaii's variable rainfall:

• Prevents waterlogging during heavy rains
• Provides moisture reserve during dry spells
• Reduces need for frequent irrigation

Yes - it's one of the best materials for raised bed construction:

Layering System:

1. Bottom layer (3-4"): Pure black cinder for drainage
2. Middle layer (6-8"): 50/50 topsoil-cinder mix for root zone
3. Top layer (4-6"): 70/30 topsoil-cinder mix for nutrient-rich growing area

Benefits:

• Prevents waterlogging and root rot
• Reduces soil compaction over time
• Improves root aeration
• Lighter than pure soil (easier to build/move beds)
• Excellent for heavy clay areas

Yes - 100% safe and approved for organic growing:

• All-natural: Unprocessed volcanic rock
• No additives: No chemicals, dyes, or treatments
• OMRI equivalent: Meets organic standards
• Won't impact certification: Safe for USDA organic farms

Black cinder is just volcanic rock - one of the most natural soil amendments available.

• Minimum Order: 1 cubic yard
• Delivery: Available (call for areas and scheduling)
• Pickup: Available by appointment at Mountain View location

How to Order:

1. Call Rick: (808) 425-0474 (Hawaiian Time Zone)
2. Specify quantity: How many cubic yards you need
3. Discuss delivery: We'll arrange convenient delivery or pickup
4. Payment: Cash, check, or credit card at delivery
5. Hours: Monday-Saturday, 8 AM - 4 PM Hawaiian Time

Bulk Orders (10+ yards): Call for special pricing and scheduling (Hawaiian Time Zone)