Soil Evaluation, Conditioning, and Enrichment

Southern California’s Mediterranean climate (also sometimes called “Dry-Summer Subtropical”), has an average of 263 sunshine days and only 35 days with measurable precipitation annually. This makes for great beach weather, but can be harsh on the soil!

With an advanced education in Agronomic Engineering (as well as Landscape Design), owner Mariela Guastavino has tended gardens on three continents and in numerous climate types. She has almost twenty years of experience in evaluating, conditioning, and nurturing a wide range of soil profiles, specializing in those that occur in Southern California.

At Le Quattro Stagioni, the goal is always to work with your garden, not just on it. To awaken the soil’s full potential in ways that are safe, sustainable, and effective, and that produce optimum growth, vibrant, colorful blooms, and full fruit trees.

Unless proactively tended to, soils become highly compacted and nutrient-depleted. This negatively impacts the health of flowers, trees, shrubs, lawns, and other garden populations. Soils require the ongoing addition of organic materials—in the form of compost, seaweed, etc.—besides fertilizers, to create a solid foundation (a “soil foodweb”), where highly beneficial microorganisms and friendly bacteria coexist.

A healthy food web occurs when:

“... all the organisms the plant requires are present and functioning. Nutrients in the soil are in the proper forms for the plant to take up. It is one of the functions of a healthy foodweb to hold nutrients in non-leachable forms so they remain in soil, until the plant requires the nutrients, and then the plant “turns on” the right biology to convert the nutrients into forms the plant can take up (but which are typically very leachable).

“The correct ratio of fungi to bacteria is present, and ratio of predator to prey is present, so soil pH, soil structure, and nutrient cycling occur at the rates and produce the right forms of nutrients for the plant.”

- Dr. Elaine Ingham, Soil Foodweb

Skillfully developing and enhancing your soil’s profile, Mariela and your assigned team may recommend and include any of the following practices:

  • Identifying soil composition and chemistry. Initial analysis recommended, and then every two years.
  • Removing significant debris (perhaps left from the original construction of your home) that undermines plants health.
  • Balancing the topography of the terrain by bringing in new dirt to replace what is removed, while preserving the natural character of your garden and any attractive undulations or mounds that may exist (unless you wish them removed).
  • Developing and maintaining an evolving, amendment, mulching and fertilization program.
  • Applying select, custom-blended organic fertilizers tailored for each area of your garden, its specific plant materials, and by season.
  • Nourishing the earth with compost and materials such as kelp, seaweed, mycorrhizae, and other organic elements as needed that will support a healthy base where plants can truly thrive.
  • Adjusting your customized fertilization program to your garden’s evolving needs.
  • Amplifying the soil enrichment program with deep cultivation (two or more times a year), especially to allow shrubs to compete successfully with larger trees. This ensures that smaller plants can get the water and nutrients they need.
  • Ensuring your soil receives the correct amount of irrigation.

* While debris removal can be a time consuming task that needs to be done by hand—no machinery will remove a thin layer of dirt—the return on the investment of this time is very high. Time spent here will save many hours in future maintenance costs.

To schedule an evaluation and walk-through, or to learn more, please call us at: 310-452-5064 or contact us via email at

We look forward to the pleasure of visiting your grounds and learning more about your dream garden!