What to plant in your Sonoma County garden

Question: We moved here from the Chicago area last year to be closer to our daughter and her family. I’m finally ready to start recreating the garden I left behind, but my daughter says I shouldn’t grow the flowers I love (peonies, lilies, etc.) here in Sonoma County. Why not?

Answer: While it may be tempting to add old favorites to your garden, choosing plants that fit your local climate has many benefits.

The adage “right plant, right place” tells us to create beauty in our gardens with the plants that fit our gardens’ unique conditions, including climate, soil, light and moisture levels. It’s also about proper placement, considering the size a plant will be at maturity (particularly important with our area’s risk of fires). That might be why your daughter discouraged you from planting your old favorites here.

For example, some peonies might find a Sonoma County garden inhospitable. According to the American Peony Society, peonies grow best in USDA Hardiness zones 3 to 8, which have cool climates and long periods of winter chill that help buds set.

Sonoma County has a Mediterranean climate that’s typified by mild, wet winters and hot, dry summers. The American Peony Society also says peonies require the most moisture in spring and fall, which happens to be when rain is tapering off or nonexistent in Sonoma County. In light of our extended drought, you can see why our local conditions would be tough on some of the plants you grew in Chicago.

This isn’t to say you can’t have a beautiful garden here. “Right plant, right place” means choosing plants that thrive in your climate.

Four other regions in the world share our local climate type, and all are on the western edge of continents in roughly the same latitude: Chile, Southwestern Australia, the Cape region of South Africa and the Mediterranean basin, from which this climate type gets its name.

In each of these places, summers are hot and dry and winters are mild with irregular rainfall. Choosing plants that thrive in one of these areas will give your new garden the best chance of success.

You’ll have a wide range of beautiful and exotic plants to choose from, including proteas, agapanthuses, crocosmias, kniphofias, nerines and common herbs like rosemary, fennel and sage.

Be sure to include California native plants in your design. Not only have these adapted to our climate over thousands of years, they also provide critical food and shelter to local birds, bees, butterflies and other insects that pollinate our fruit, vegetables and gardens.

There’s more to “right plant, right place” than choosing a plant from a similar climate. Understanding your garden’s soil structure, light and moisture conditions is also important.

In Sonoma County, your garden might have rocky soil, which tends to drain well. Plants with low-water needs, such as salvias, agastaches and lavenders, don’t tolerate soggy soil but can thrive in rocky, well-drained soil.

However, if you have clay soil, which tends to retain water, there are plants that are better-adapted to moist conditions, such as black-eyed Susan (Rudbeckia hirta), blue oat grass (Helictotrichon sempervirens) or foothill penstemon (Penstemon heterophylla).

Also, consider how much light your garden gets throughout the day and which direction your garden faces. Light in Sonoma County can be intense, particularly in the summer. The plants you choose may have very different light requirements.

Most of all, pay attention to how much water your new plants need. Using plants from areas with a Mediterranean climate won’t guarantee drought tolerance, as some plants from these areas require more water than others. Given our dry climate and current drought, focus on plants that require little to no water.

If you must grow peonies and lilies, consider California native species of these plants. While not as large or showy as the peonies you had in Chicago, the low-maintenance California peony (Paeonia californica) can be attractive, with its deep red petals and gold stamens. Many of our native lilies also can add grace to your garden, including the Humboldt’s lily (Lilium humboldtii), coast lily (Lilium maritimum) and tiger lily (Lilium pardalinum).

Regardless of which plants you choose, remember to plant in fall to minimize watering and give roots a head start before summer comes. And thank your daughter for giving you wise advice.

For more information on planting in the Sonoma County climate, go to bit.ly/3rbbJyM or bit.ly/3LQN9fW.

For information on California Natives, go to bit.ly/3fkl8kV.

Contributors to this week’s column were Patricia Rosales and Rob Williams. The UC Master Gardener Program of Sonoma County (sonomamg.ucanr.edu) provides environmentally sustainable, science-based horticultural information to Sonoma County home gardeners. Send your gardening questions to scmgpd@gmail.com. You will receive answers to your questions either in this newspaper or from our Information Desk. You can contact the Information Desk directly at 707-565-2608 or mgsonoma@ucanr.edu.