Ideal Planting Times Workshop

By Autumn Yanez-Jacobo
Research Coordinator for Earthwatch’s Community Gardens Project

On November 16, 2019, nine members of the local community and participants in the Earthwatch Community Gardens research project met at Huerta del Valle to learn about ideal planting times for seeds. This was a topic that was highly requested by participants in the program through word of mouth and responses from our monthly surveys. Many knew what to plant in the Spring and Summer, but there was less knowledge about what to plant during cooler times of the year and they wanted to learn. They wanted to be able to have things growing year round, and never have an empty garden plot!
We invited Julieta Muñoz from the Growing Roots organization to facilitate this workshop.  Growing Roots is “a non-profit organization that strengthens community through building and maintaining urban farms and gardens in southern California.” Julieta is an urban farmer with a degree in Plant Science and a minor in Soil Science from Cal Poly Pomona.
Participants learned the best seasons for planting different types of vegetables in order to improve harvest, reduce pests, and save water. Julieta explained how California has 3 major growing seasons, the cool season, the cold season, and the warm season. Planting during the correct season can help to avoid pests and diseases, and increase leaf coverage for optimal photosynthesis.
Cilantro, broccoli, and kale can be planted in cool weather. Cabbage, beets, and spinach can be planted in cold weather. Tomatoes, peppers, and eggplant can be grown in hot weather. One concern voiced by many participants was that their cilantro was not germinating during the warm season. From this presentation, they learned that cilantro actually does best when planted during the cool season, not the warm season.
After the presentation, participants and community members planted their own lettuce, carrot, and cauliflower seeds in seed trays.  Overall, the workshop was a success thanks to Julieta, the participation from community members, and the wonderful participants in our research project!


Operation Healthy Air Report Now Available!

In 2017, a team of community members, scientists, and local organizations came together to assess local air temperature and ozone changes from yard to yard, and from neighborhood to neighborhood in Southern California to help inform how best to adapt to dangerous levels of pollution and severe heat. Operation Healthy Air (OHA) engaged more than 1,000 community members who contributed their time, energy, and insights to collect data at over 230 sites. Our team has started to analyze the data and has presented some preliminary results in this newly released report.


Climate change is predicted to exacerbate health challenges in cities, especially the conditions that impact poor communities most. Generally, attention and funding are drawn to the catastrophic events associated with climate change, such as coastal storms and areas with high risk for financial losses. However, urban and heavily developed suburban communities are subjected on a daily basis to the effects of climate change in the form of high temperatures which when combined with reduced air quality promote chronic health problems.

Ozone Levels

The rate of death due to high Ozone levels is higher in cities (LA/Long Beach) compared to less urban environments (Riverside/San Bernardino). Ozone is formed when the right ratio of specific types of air pollutants are exposed to sunlight and heat. Ozone is a toxic pollutant that irritates and damages lungs and other tissues.

Deaths per year due to high Ozone levels:

  • 3,255 for Los Angeles – Long Beach – Glendale
  • 1,416 for Riverside – San Bernardino – Ontario area

Number of times people called in sick, missed school, etc. because of air pollution:

    • 2.9 million dates in LA
    • 1.3 million in the inland area

Ozone levels change significantly based on temperature and wind direction. Residents should avoid being outdoors during the hottest parts of the day to avoid the highest concentrations of ozone in the air.

Tree Coverage

Tree coverage is essential for maintaining cooler temperatures and cleaner air. We also found that tree size matter in helping to cool local air significantly, but only during the day. At night, the amount of pavement (especially asphalt, i.e. roads) influences temperature most.

Indoor Temperature

We also examined peoples comfort levels based on indoor temperatures. Managing indoor air temperature can minimize carbon footprint and cost. This study has demonstrated that even small differences in temperature have an impact on our comfort so paying attention to local temperature can improve your health and ability to function well. Research has also shown that people can become acclimated and adjust their temperature comfort threshold—so it is possible to adapt to warmer temperatures within reason. Try to adjust indoor air conditioners down one or two degrees to see if you can become acclimated. If that works, try to adjust down again and see what happens.

Get detailed insight into why this program was started, what setting up a study looks like, and how we implemented a large-scale research program with the help of community members.

Read the Report Here