Phil and Katherine Foster

Oct 13, 2020
Pinnacle’s Phil Foster committed to soil management

Call him a grounded grower.

Phil Foster is committed – not only to his customers and employees, and not only to his business’s success. He’s committed to the ground itself.

Although most organic growers would profess some dedication to healthy soil, he’s dug a bit deeper, getting heavily into composting, elaborate cover crops and reduced-tillage agriculture. He said that commitment is not only addressing environmental sustainability but also the very practical concerns of staying in business.

Foster was the grower on a panel of speakers last December at the Organic Grower Summit in Monterey, California, where Haley Baron of the Organic Farming Research Foundation (OFRF) organized a session on reducing risk through soil management practices.

“Be it drought, be it inclement weather, be it pest cycles that are changing – there is a lot going on in the farm, and there’s a lot of potential risk,” Baron said in introducing the speakers. “However, perhaps the greatest risk of all is the loss of the hardworking capital – your healthy, fertile soil. And compaction, declining soil organic matter, decreased fertility, soil erosion are all silently undermining production.”

The OFRF recently released a series of publications on best practices for reducing risks faced by organic growers.

“We feel that soil erosion and degradation is perhaps the greatest threat of all,” Baron said. “And we know while hail can destroy the current crop and issues like compaction or low fertility can be corrected within a few years, it takes nature some 500 years to replace an inch of topsoil lost to wind or soil erosion.”

Stability for survival

Foster, whose farm operation has been organically certified for 30 years, said he originally turned to organic growing for economic reasons.

“In 1989 we experimented with our first organic production,” he said. “Five acres we experimented with. … The economics of it seemed like this was a way to stay in business and this certainly has sustained us well for a number of years.”

The farm includes 95 acres in San Juan Bautista and 200 acres on a Santa Ana Ranch. Soils range from sandy, silty loam to clay loam. The growing operations include 5 acres of hoop houses that help with season-extending and winter production and a four-acre compost yard. The farm grows 60 different types of vegetables and tree fruit. For 20 years, Phil Foster Ranches has marketed its produce under its own brand, Pinnacle.

“We do some local marketing,” Foster said. “Seventy-five percent of what we grow is marketed within 100 miles of the farm. So, we do this through farmers’ markets, direct delivery to stores, and working with a couple of regional wholesalers.”

But it wasn’t just the economic reasons that drew him into organics.

“The other thing I was interested in was the soil-building aspects of organic farming: cover-cropping, composting, (bio)diversity.”

Foster, who regularly has the soil tested, said he’s been able to up the percentage of organic matter in his soils by one percentage point over the years. The San Juan Bautista ranch currently is at 2-3% organic matter, while the Santa Ana Ranch has 3.5-5.5%.

“There is really a big difference with this kind of organic matter,” he said. “The crops are a lot healthier, there are very little extra fertility inputs we need other than our composting/cover cropping. They’ve sustained us very well.”

Building better soils

During the farm’s early years, Foster bought compost, applying a couple of tons per acre per year. In the mid-90s, he set up four acres on the farm to produce compost. The thermophilic, aerobic, managed windrow compost facility produces between 1,500-2,000 tons a year, Foster said. And all of it is used on the farm at a current rate of about 5-8 tons per acre.

Inputs include “clean, green material” from urban areas, wheat straw or wheat hay, the farm’s cull vegetables and various manures from dairy cows, horses and even a local duck farm. The material is processed in 400-foot long windrows, which Foster said each is about 100 tons. A special compost turner allows the farm to turn or mix a compost windrow in about 20 minutes.

Using manure in compost for vegetable and fruit production means that the thermophilic process – in which the raw materials begin to break down and heat up – should help to kill off bacteria and pathogens.

“We do keep detailed records, as part of our certification requirement, our food safety audit, our oversight from the state of California,” Foster said. “They want to see our compost records and this is part of our risk management using manures. Historically, manures have been great for soil building, but you get a lot less nutrient loss, much more stable nutrients, more biology, and, especially with the manures, less impact from pathogens. We’re running between 130-150° F here for almost a 23-day, 25-day period, and turning the compost, getting all exposed to the temperature. And this reduces risk from the pathogens in the manure we use in our compost.”

In addition to temperature-taking, Foster sends compost samples to a lab to test for levels of fungi, bacteria, pathogens and the compost’s physical properties.


Cover cropping and low-till practices help keep away weeds, keep the dirt in place, and keep the organic content of the soil high.

Cover crops are often flat-planted with a grain drill in the fall over winter taking advantage of winter rains.

“I know that it is hard to work cover crops in sometimes, but there are strategies for getting them in quicker,” Foster said. They will sometimes plant Lana Vetch with a single-line planter and six weeks later follow up later with another cover crop to fill the space.

“We’ve wanted to get cover crops into our rotation more,” he said. “We’ve experimented with spring cover-cropping, fall, winter cover-cropping.”

Although Foster does have a couple “workhorse” cover crops, including Lana Vetch – he varies the mix of cover crops based on what the crops for the field will be during that rotation.

For instance, in a mix for a summer cover crop, he includes sunflower, phacelia, flax, clovers, pearl millet. A winter cover crop includes Lana vetch, some sudangrass, buckwheat and mustard.

“We get quite a nice coverage,” he said. “We mow it and then we can work it into the soil.”

Better organic content helps on several fronts.

“I always like to say ‘pennies from heaven’ when we get a nice rain,” Foster said during what had been a wet year by California standards. “And in this case, we’ve been getting quarters and silver dollars from heaven. So, if we have soils with higher organic matters, they work more like a sponge, and they’re able to soak up that water and keep it in the soil profile.” He said the organic matter also buffers salts in the soil and well water.

Reduced tillage helps keep the soil in place. For fruit trees, it’s easy to have an “understory” with plants, but Foster has found it is necessary to prepare the ground at least a little bit for vegetables.

“In vegetable production, it’s a lot larger challenge to do reduced tillage,” Foster said. “If we can grow onions and carrots on these trees, we can reduce tillage in vegetable production,” he said, earning some laughter from the audience.

A vertical tillage piece of equipment – straight blades in front, wavy ones in the back and soil chisels to dislodge roots allows him to prepare the soil without actuall inverting or turning it.

There’s a bigger-picture aspect to capturing carbon, soil conservation, and planting cover crops that cover the ground green almost year-round. But Foster emphasized it’s also good for farming.

“All of these practices utilizing cover cropping, composts, reduced tillage, diversity, living roots, are enhancing our soil health and is resulting in a better crop and crop resilience, which is also giving this hopefully better-quality crops for our customers,” he said.

On The Web

For more on how to manage farm risk through organic growing practices, visit

Stephen Kloosterman, associate editor

Tags: ,

Current Issue

Cover image of Fruit Growers News (FGN) July 2024 issue.

Talking tech: New app innovations aid growers

Smart tech wipes out pests: The latest trends in spraying automation

New Geneva rootstocks to help apple growers with size, yield, disease

Georgia peach success: Pearson Farm’s six generations find orchard happiness

FIRA preview: Tree fruit tech options abound at ag robotics conference

Fresh Views: Grapevine disease management tackled

Farm Market & Agritourism: Insights from the 2023 farm markets survey

National Plant Diagnostic Network


see all current issue »

Be sure to check out our other specialty agriculture brands

produceprocessingsm Organic Grower