FAQ's

I understand you have OMRI listed compost for sale that can be used in certified organic production. Can you provide the rates for the materials?

Yes, we produce OMRI listed compost at our Z-Best Composting Facility. These materials may be used in certified organic production or just in your home garden. We are one of the largest composters in California, and deliver quantities of compost products from 1 yard to 1,000 yards. Materials can be ordered on this site or by calling 408-586-9292. If you would like a price quote for a large volume of materials (more than 24 tons), please contact Scotty Pische at 408-846-1574 or email Scotty at scotty@zankerrecycling.com.


I see you offer “high volume discounts” for aggregate purchases.  What is considered a “high volume” order?

High-volume discounts are usually on orders of one thousand or more tons. However, we will extend a discount for orders less than the typical high-volume amount for certain materials that may be particularly abundant, or for an order that might be considered “high volume” for a certain industry.


How much does 1 cubic yard of crushed rock aggregate weigh? 

While all of our aggregates vary by several hundred pounds per cubic yard, we use 1.5 tons (3,000 pounds) per cubic yard.


Where does the compost come from?

All our compost products are made at the Z-Best Composting Facility (Z-Best) located in Santa Clara County near the City of Gilroy. The facility generates these products from composted residential yard trimmings.


What is the compost made from?

The compost sold at Zanker Landscape Materials is produced from composted residential yard trimmings and is listed by the Organic Materials Review Institute (OMRI – www.omri.org) and may be used in certified organic production. OMRI is the “gold standard” for organic review. No food waste, manure or paper waste is used in the production of the Z-Best Organic Compost.


Why is our certified organic compost preferred over synthetic fertilizer use?

Our compost is nutrient-rich and is a living organism. Naturally-occurring organisms in the compost change and improve the product over time, until the compost becomes a soil organic matter called humus. Synthetic fertilizer does not compare to humus because the organisms in it are essentially handicapped. Synthetic fertilizer contributes only to the plant’s well-being, not the soil’s. Our compost feeds the soil first, and the plants benefit greatly. If your soil is healthy, your plants will become healthier as well. 


How is the compost product processed? Is it pathogen and weed-seed free?

In accordance with California State Regulations, the compost needs to be kept at 131 degrees Fahrenheit for 3 days, ensuring all pathogens and unwanted weed seeds have been destroyed. The compost will continue to mature and break down after application (on a farm or on front or backyard gardens) and helpful microorganisms, bacteria, and insects will re-populate to create a living, fertile soil substrate for your plants and vegetables!


What sand should I use for “Paver Sand”?

Utility Sand – Recycled (aka Concrete Sand or Quarry Fines) is commonly used as “paver sand” for things like setting bricks in walkways and patios.  If you need a sand product to be used around metal pipes, we recommend our Fill Sand.


What is the cost comparison between a standard bag of material you can buy from a hardware store or nursery and bulk, wholesale products?

The average bag of compost at a home store costs $4.00, and each bag contains about 1 cubic foot of compost. 1 cubic yard, or 27 cubic feet, of home-store compost would cost $108. Zanker Landscape Materials sells its Z-Best Organic Compost for $24 per yard, which is 22% of the cost of a bagged product.


How is the mulch product processed, and is it pathogen and weed-seed free?

We separate clean lumber from incoming loads of wood waste.  This lumber is ground to a uniform size, and dyed with a safe, water-based dye specific for mulch use. It is then sold as a top-grade recycled-mulch product.


What is Class II Base Rock - Recycled?

Class II Base Rock – Recycled has multiple names: Base Rock, Class II AB, AB and Road Base.  Class II Base Rock is a recycled, crushed aggregate that is no larger than ¾”. This product also contains fines.  The material is engineered with larger ¾” rock to help create drainage while the fines aid in compaction.  Hundreds of thousands of tons of our Class II Base Rock are used each year for a variety of purposes, including as backfill and as a construction material for roadways, walkways, or pads.  It is also a cost-effective and environmentally-sound alternative to “virgin” material.


What is 3/8” Pea Gravel?

Our 3/8” Pea Gravel is a crushed concrete aggregate that is screened to a size of roughly 3/8”.  When crushed, the aggregate becomes angular and thus is more like a Pea “Chip.”  Our Pea Gravel has a number of uses: as a pathway material, for drainage rock (French drains), under pavers, and others.  It is also more cost-effective and environmentally-sound than “virgin” material.


Is the dye that is used in the colored mulch safe to use, particularly around pets and children?

Yes. Zanker Landscape Materials uses colored mulch produced with Heartland.

Enriched Colorants and are safe for use around the home. Independent laboratory tests have confirmed that colored mulch presents no more concern for children or pets than regular mulches.  Heartland avoids using any hazardous or threatening material in its colorants. To make colorants, Heartland Enriched Colorants uses materials also used in products like lipsticks, cosmetics and food containers. Heartland has always used water- based formulations (rather than solvent-based), and periodically the company invites independent laboratories to test the colorants to confirm that its Colored Mulch is non-toxic.  www.amerimulch.com.


Will your mulch encourage termites to live by my house?

In general, the heat generated from the composting process will kill just about anything in the mulch piles. Also, a thin layer of mulch is not an ideal environment for termites. They prefer dark, solid and isolated environments.


Are the dyes you use in your mulch going to permanently stain my property?             

Once mulch colorant is locked onto wood fiber, the color permanently bonds and does not wash off. However, even using proper application procedures, stains can occur. Even if the color looks dry, precautions should be taken to avoid staining driveways, sidewalks. Mulch should be laid on tarp when possible, and water should be applied to the surfaces before mulch is set down. Once the mulch is distributed, wash the area or tarp with warm, soapy water to prevent the color from permanently staining the surface.  In addition, to prevent staining your skin, wear gloves during the application process.


Are your mulches treated with any chemicals?

Our mulches are not treated with any sort of chemicals or pesticides.


Can I use compost as mulch?

Absolutely! In addition to holding in moisture and deterring weed growth our compost also provides important macro and micro nutrients to help plants grow healthy and strong.


What’s that smell?

Regardless of the source, composting, organic matter will release an odor during the composting process. It’s true with hardwood mulch, animal manure, yard waste and other types of compost. But that’s an indication of the beneficial activity going on within the compost. A slight odor will remain until it is spread, tilled, or watered in and will quickly diminish within a day or two.


What's the down side to using compost?

It may be hard to believe but there isn’t a down side! Through the use of recycling and the beneficial use of organic waste, we are all helping to relieve the growing problem of overcrowded landfills. And compost will help you grow healthier plants with larger, more colorful flowers and greater vegetable yields!


I normally buy bagged mulch. How can I figure out how mulch bulk mulch to order?

Please refer to our cubic yard coverage calculator.


How many square feet will one yard cover?

At a depth of 2 inches, 1 cubic yard will cover 162 square feet.  For more conversions please refer to our coverage calculator.