Contact Filoli | eNewsletter Sign Up

donate now login

Filoli’s Drought Response

More Information

Click on the images below to visit each online resource and article.


UC logo

National Integrated Drought Information System

Drought In California page

Save Our Water

California Dept. of Water Resources and the Assoc. of California Water Agencies

UC logo
UC – Drought Info

University of California, California Institute for Water Resources

breaking waves
Future Of Water

Sunset Sparks Conversation About the Future of Water

Recent Drought Coverage in the San Francisco Chronicle:

Store or Conserve?

California drought puzzle: store or conserve more water?

baby blue eyes
Natives for Spring

Smart, colorful natives for spring

native grass
Grass Lawns

Drought bringing an end to the water–guzzling grass lawn

Growing Food

Drought gardening: tips for growing food

view of north field and back of house

A view across the north field to the back of the House. Photo by Jerry Barrack.

With record low rainfall for the 2013–2014 season, Filoli is taking several measures to reduce its water use this spring, summer and fall. Typically our garden uses a great deal of water during the summer months, but our efforts should considerably reduce that quantity this year.

The source of Filoli’s water is partly from our three wells and partly domestic water from Crystal Springs Reservoir. In a wet year, most of our irrigation water comes from our wells, but with fifteen months of very low rainfall, our wells are not able to keep up with our demand. In fact, two of our wells are completely dry, and the third can only supply a tiny fraction of our needs. Although we can purchase all the water we need from the neighboring reservoir, we feel we need to play our part in conserving like everyone else. The other consideration is the impact purchasing additional water will have on our finances.

After the Bay Area’s last significant drought in the 1980s, Filoli installed an irrigation system in the garden. Prior to that, all our irrigation was done using hose–end sprinkler heads. Upwards of two full workdays each week were spent manually watering the garden during the summer. Such an inefficient system led to a great deal of waste (both water and time), hence the decision to move to an automated system.

We feel we already do quite a lot to prevent the over use of water at Filoli. Our irrigation schedules are based on CIMIS (California Irrigation Management Information System), which uses historic weather data to predict evapo–traspiration (a measure of plant water use), and plant requirements based on plant type (turf vs. annuals vs. woody plants). This is then fine–tuned for specific microclimates within the garden like slopes, turf adjacent to a hedge, compacted soil, etc. With a good irrigation system, we are able to keep our plants supplied with just enough water to thrive, without much waste.

The other key to having an effective and efficient irrigation system is continuous monitoring by trained horticulturists checking the system for any troubles. Filoli staff perform a complete check of all our irrigation systems each spring correcting for broken or misaligned sprinkler heads and inspect for any cracked and broken parts. Then, throughout the dry season, our irrigation systems are monitored. Historically dry areas are regularly probed to check the water content of the soil. An irrigation system is only as good as the horticulturists who maintain it. You cannot be on autopilot and expect the system to take care of itself.

In the face of this severe drought, our plan is to operate under a philosophy of allowing parts of the garden to thrive, while other parts will be irrigated just enough so that the plants are able to survive. All display beds and highly visible sections of the garden will receive our standard irrigation amounts. A few of our less visible lawns will be allowed to go mostly or completely dry. Woody plants can survive with 40% of normal irrigation, so many of our orchards and other woody plants will be irrigated significantly less this summer and fall.

Filoli’s Planned Water Conservation Measures

  1. Irrigate woody plants at 40% of normal levels.
  2. Refrain from irrigating olive orchards, blue Atlas cedars and other stands or woody plants normally receiving monthly summer irrigation.
  3. Replace current irrigation nozzles with low flow irrigation nozzles where appropriate. Potential water use reduction of 30% per irrigation zone.
  4. Partially reduce the number of containers in the garden and, for the most part, choose more drought tolerant varieties, like Pelargoniums (geraniums).
  5. Allow some low–visibility lawns to go dry for the summer. Currently planning for 40% (40,000 sq. ft.) of turf to receive either no or reduced irrigation. We may experiment with artificial color sprays to give these lawns a greener appearance.

Turf Areas scheduled for significant water reduction and planned order of reduction:

    First group— irrigation already turned off:
  • North lower lawn terrace (field view to the north)
  • North Ballroom Lawn
    Second group— irrigation presently reduced 50% to keep presentable through peak tour season; turned off or reduced to 30% if turf irrigation system also irrigates adjacent woody plants:
  • North and South Upper Terraces (behind house)
  • Behind Swimming Pool Pavillion
  • Both yew allees along swimming pool
  • Wedding place terrace lawns
  • High Place
  • High Place yew allee
  • Service courtyard lawn (outside admin. Offices)

Recommendations For Your Garden

Many of these practices apply to any year in California, but they are particularly applicable for 2014:

  1. Thoroughly check your irrigation system for any troubles. If you are not comfortable performing this type of check yourself, consult an irrigation specialist.
  2. Regularly monitor your irrigation system throughout the year to identify troubles as they arise and address these as quickly as possible.
  3. Make sure to schedule irrigations for pre– or post–dawn start times with the exception to plants susceptible to flower fungal disease (Botrytis) like petunias.
  4. Consider transitioning to drip or micro–spray irrigation wherever possible to conserve water.
  5. Cut back irrigation of woody plants so that they receive 40% of what they have in the past.
  6. Refrain from adding new plants to your garden this year. Choose low water using California natives, Mediterranean plants or succulents if you must plant.
  7. Faced with reduced food in their natural environment, expect deer to be more brazen about feeding any time of day and feeding on plants that are typically considered “deer proof.” If browsing deer have been an issue in your garden in the past, this may be a good year to consider installing a fence.