This year’s Fall Equinox lands on September 22, marking the unofficial start of the planting season.

Installing new plants in your garden during the fall provides them time to establish roots and prepare for leafing out and blooming in the spring. Ideally, we would have our historic pattern of winter rains during this time, so that the plants will have ample moisture to work with.

An additional benefit of this planting schedule might include end-of-season plant clearance sales at your favored garden center or nursery. You can feel like a savvy garden shopper when you acquire plants at good prices in the fall, and resist the temptation to stock up in the spring, when small plants have been forced into seductive blooms with nitrogen fertilizers.

The planting season is still a couple weeks away, so right now is a good time for planning to select and install plants in your garden. Having a plan when you open a mail order catalog or walk into a garden center will prepare you to focus your targets and avoid becoming overwhelmed by the array of possibilities.

Strategies for garden planning in the Monterey Bay area include emphasizing drought-tolerant plants, or California native plants, or a particular theme of your own choosing. Earlier versions of this column have addressed such strategies.

Today’s column describes additional strategies suggested by Rochelle Greayer, author of Cultivating Garden Style (Timber Press, 2014). In her online newsletter, Pith + Vigor, Greayer recently identified three mistakes that gardeners make when designing with plants:

• Too many different plants
• Not enough plants
• Planting just the plans you know.

Let’s consider positive strategies in these three areas.

First, develop your landscape around a just nine to twelve different plants. Selecting plants in this short list for specific roles will bring order and cohesion to the landscape, and avoid the chaos that too often results from impulsive additions of individual plants.

Second, once you have selected your short list of plants, install lots of them. This strategy is related to adding plants in clusters of three, five, or any other odd-numbered quantity, to present them in a natural and pleasing manner. As you reach larger numbers, install the plants in swathes or bands to provide a landscaping effect. Greayer says, “Repetition gives a scheme flow and rhythm. Repetition is a savvy designer’s best trick.” For example, I recently planted two parallel arcs of blue and yellow irises as a color statement for next spring. Over the next few seasons, these plants will increase to provide increasingly dramatic displays.

Related to the idea of repetition planting is the installation of plants with close spacing. While you might be tempted to spread plants out to cover space in the garden, having open areas between plants reduces their visual impact and invites the growth of weeds. Close spacing reflects the natural tendency of plants to propagate and develop into colonies. It also functions as “green mulch,” denying weeds the sunlight they need to develop.

Third, explore the wonderful world of plants to find good choices for your short list of selections for the landscape. It’s always important to select plants that are suitable for the climate, soil and exposure of the locations for which you are planning, but there are always many interesting selections that are both suitable for your garden and new to your experience. Relying on common and familiar plants will doom your landscape to being (gasp!) ordinary. Discover interesting plants that will bring excitement to your garden, and invest time in learning how to cultivate them successfully.

In review, there are three strategies for planning the development of your garden during this planting season: develop a short list of plants, install significant numbers of each kind of plant, and select some unfamiliar plants that will fit into your plan and provide a fresh new look to your landscape.

Enjoy this fall’s planting season, and your garden’s coming spring!