Making & Using Compost
Part 1 – 330 | Unit 1.7
SUPPLEMENT 2
Field-scale Compost Production at Phil Foster
Ranches: A Case Study
Phil and Katherine Foster farm 295 acres of vegetables and fruits on two certified organic
ranches in San Juan Bautista and Hollister (San Benito County, California). At peak season,
they work with a crew of 55 employees to produce more than 60 different crops, which are
direct marketed through ten regional farmers’ markets and a popular roadside stand. Phil
also sells to numerous retail stores, where the Pinnacle Organic brand is a familiar sight to
shoppers from Carmel to the San Francisco Bay Area.
Phil Foster is regarded as one of the region’s most
successful and progressive organic growers, in large
part because of the craftsman-like approach he takes
to building and maintaining healthy soil. He’s the
first to say that the compost he uses in his operation,
produced on his Hollister ranch, is one of the keys to
the exceptional quality and abundance of Pinnacle
Organic’s produce (www.pinnacleorganic.com). Phil
generously offered to share the story of his compost
operation during a visit to the ranch in spring 2014.
Background
After working in the conventional produce industry
in California’s Central Valley, Phil started farming
organically in 1988 (both his ranches are certified
organic by the California Certified Organic Farm-
ers, CCOF). He initially spread manure on his fields
in the fall to replenish organic matter following the
cropping season and ahead of the winter rains, then
switched to buying in commercially made compost
from New Era. After attending a seminar on the
Luebke compost production method^1 (also referred
to as controlled microbial composting) at the nearby
Herbert Family Organic Farm, Phil started making
his own compost at the Hollister ranch in 1995. The
compost yard now covers 4 acres, where his com-
post crew produces 2,000 tons of finished compost
annually, enough for all of both ranches’ needs.
1 Read more about controlled microbial composting at
http://www.herbertfamilyorganicfarm.com/Compost.html
Labor, Machinery and Compost Yard
Set Up
Originally, the operation used an 8’ self-propelled
compost turner and a Zeton spreader from Farm-
ers Equipment. Phil has since switched to a used 10’
Sandberger pull-behind machine upgraded by HCL
Machine Works (www.compostturners.com) in Dos
Palos, California, which he purchased for $7,000
(new units run approximately $20,000). He had
the machine rebuilt with common drum bearings to
make it easier to fix in-house.
Other equipment used in the operation includes:- Tractor with creeper gear or hydrostatic trans-
mission for pulling the compost turner. Phil’s
crew runs it with an 80HP orchard tractor or
a 90HP JD6410. You need roughly 10HP per
foot of compost (10’ to 80-90 HP). - Wheel loader for moving feedstock, building
windrows, and loading finished compost (he
purchased his used for $10,000). - Instruments to measure temperature, CO 2 pro-
duction, microbial life levels (approximate cost
$500).
Other compost yard considerations: - Access to a water source to wet down compost
during turning. Pinnacle’s operation uses a
dedicated tank with a trickle-fill system at 5 gal-
lons/minute, so as not to disrupt the irrigation
system. - Adequate space to accept deliveries of large
loads of feedstock and to store finished compost - Proper grading to shed water and prevent
pooling.
Supplement 2: Field-Scale Compost Production