San Diego County climate zones are many and varied. Whether you elect to plant seasonal vegetables or create a garden to support learning about Native American culture, choose plants that do well in your local climate zone. Plants that thrive along the coast might succumb to excess heat or frost inland and, conversely, cool Summer weather makes it difficult to grow certain varieties of vegetables in coastal areas.
You will also need to know if the plants you chose need full sun, partial shade or full shade. Vegetables generally require six hours of sunshine daily. Check the water needs of the plants you choose. Many need moderate water but some are thirstier, and others, such as succulents, thrive with minimal water. After they are established, natives want little water during the summer. You will want to group plants in your garden by their water needs.
Consider the season when vegetables and fruits will mature and flowers will bloom. Edibles, annuals and perennials generally produce their fruit or flowers in a specific season. For example, tomatoes are a summer or warm season crop; broccoli is planted in the Fall to mature in Winter or early Spring. Likewise, poinsettias bloom in Fall and pansies cheer us during winter. Ultimately, you want to coordinate your plantings with the school year.
Regardless of what you decide to plant, consider its mature size and allow it the space it needs. Leave sufficient room for the plants to achieve their mature size without crowding or overwhelming other plants. Also consider the invasiveness of some plants (e.g., Jerusalem artichokes or mint) that are best grown in containers. The Sunset Western Garden Book provides a wealth of information to guide you in your selections.
Consider the compatibility of the various plants you want to grow. If planting beds will contain diverse plants, group the plants by their cultural characteristics: water needs, sun/shade requirements, size at maturity and whether they are annuals or perennials. It is possible to have plants with various water needs in one bed; however, it is best to group them according to their water requirements.