Design trends

Gardening in Sandy Soil

Common in the Santa Cruz mountains, Bush Poppy bloom readily in sandy soils.

Many years ago I started writing a book about Gardening in the Santa Cruz Mountains. One of many interesting subjects I researched was the different soils we have here in the mountains. I don’t need to tell you if you garden in dense clay, serpentine soil or that sandy soil like being at the beach that our soils are challenging. That sandy soil? Well, it’s because we used to be a beach eons ago before the land rose up out of the sea. Here are some tips for those who live with sandy soil.

The distinct region of the Santa Cruz sandhills, with its gritty, well-drained soil, presents both opportunities and hurdles for gardeners. How to turn your sandy soil into a thriving garden?

Sandy soil is composed of larger particles compared to clay or loam, meaning it drains quickly and doesn’t retain nutrients well. This is not a death sentence for your garden. You can transform your terrain into a lush, productive garden with just a few steps.

Start by improving your soil’s structure. Organic matter is your best friend. Compost can really boost your soil’s
ability to retain moisture and nutrients. Regularly adding organic matter will gradually improve its texture and fertility. Do this every year. Cover crops, such as clover or fava beans, can be very beneficial. They not only add organic matter to the soil when turned under, they improve soil structure and even fix nitrogen, enriching the soil for your plants.

Choose plants that will thrive in sandy, well-drained soil. Native plants are good choices as they are adapted to our local conditions. I see Bush Poppy ( dendromecon rigid ) thriving in the most inhospitable of places. Plants from the Mediterranean area and Australia are also good. Manzanita and ceanothus thrive in sandy soils. Rosemary, lavender and thyme do well in porous soil and are fragrant. Salvia, buckwheat, yarrow are easy to grow in sandy soils. Carrots, radishes and potatoes are ideal for sandy soils because they prefer loose, well-draining conditions. Be sure to provide plenty of organic matter and mulch to help retain moisture around your plants.

One of the main challenges with sandy soil is water retention. Water wisely, frequent, shallow watering won’t work here. Instead, water deeply and less often to encourage plants to develop deep root systems. Drip irrigation systems can be particularly effective, delivering water directly to the plant roots and reducing evaporation. Mulching is another critical practice. A thick layer of mulch helps retain soil moisture, suppresses weeds adding organic matter to the soil as it decomposes.

Because sandy soil doesn’t hold nutrients well, regular feeding is important. Organic fertilizers like compost tea, fish emulsion or seaweed extracts are great for providing a steady supply of nutrients. Slow-release granular fertilizer is also good.

The natural beauty and unique characteristics of the sandhills can be enhance by incorporating elements that blend with the landscape. Rock gardens, succulent beds and native grasses can create a stunning, low maintenance garden that harmonizes with the environment.

By understanding and working with its unique characteristics, you can cultivate a thriving garden even in the Santa Cruz sandhills.

Design trends

Tips for Gardening in Clay Soil

California Fuchsia tolerates clay soil.

Soil is a wonderful thing. It grows our food, anchors our trees and provides a foundation under our feet. But it sure can be hard to work with when it’s not the soft, crumbly loam that many plants prefer. It’s amazing that anything grows in some of the soils here in the Santa Cruz mountains. Some folks near Quail Hollow garden in an ancient sea bed of sand and there are others who have such heavy clay in their gardens that you wonder how anything survives.

I used to live up under the trees in Felton where the soil was heavy clay. Then I lived in Bonny Doon and my garden was gritty sand. Both soils have their challenges but I think clay soil is the hardest to deal with. Soil that does’t drain quickly during the winter is especially challenging. Where’s that perfect loam when you need it?

Some soils in Boulder Creek require a pick ax to break up enough to plant. Sound familiar? Although rich in nutrients, clay soil requires compost to provide the environment necessary for beneficial microbes, worms and other critters could do their work and aerate the soil. A thick layer of mulch spread over the soil helps to preserve soil structure and prevent it from packing down again. Do not add sand to amend clay soil. You’ll just create cement.

There are plants that are tolerant of clay soils but California native plants won’t tolerate standing water for any length of time. They’ll die from either root rot or suffocation as saturated soils prevent oxygen from getting to plant roots. You can plant on a slope where the water is unlikely to saturate the ground around the plant.

Search for native plants that will survive slow draining soils at Calscape- https://calscape.org. Using the Advanced Search tool you can see which plants tolerate different conditions. Enter your address to find plants for all kinds of sun, moisture and drainage situations. I found 48 plants native to Boulder Creek that tolerate slow drainage on the website. From ceanothus to manzanita to California fuchsia to Douglas iris you’re sure to find plants that look great and perform well.

There are plants from similar environments in other parts of the world that would also do well if you garden in heavy soil. One of my favorite trees for these conditions is the strawberry tree. Also hackberry, ash, gingko and paperbark trees work well also. Shrubs to try include flowering quince, bottlebrush, Australian fuchsia, smoke tree, escallonia, pineapple guava, mahonia, osmanthus, Italian buckthorn, elderberry and vitex. Easy perennials for clay soils are yarrow, bergenia, carex grasses, fortnight lily, coreopsis, echinacea, nepeta, salvia, teucrium and verbena to name just a few.

If you’re not familiar with some of these plants it’s easy to see what they look like by Googling images. It’s what I do to see a plant full grown and not just a line drawing or a close-up of the flower.

So you see, there are plants that will be successful even in heavy, clay soil, you just have to pick the right ones.

Design trends

What to Do in the September Garden

Grevillea lanigera is a good low water groundcover that attracts hummers

Summer is winding down. It’s still warm during the day but the nights are cool and there’s less and less daylight hours. The soil is still warm so it’s the perfect time to start thinking about planting. Like the saying goes, “gardening is a way of showing that you believe in tomorrow.”

Gardening makes us learn new things. If you water less frequently, some plants may decline or even die eventually. Remove those that do and replace them with plants that will thrive with less water.

Fertilize shrubs lightly one last time if you haven’t already done so last month. All shrubs, especially broad-leaved evergreens such as rhododendron, pieris, camellia, hebe, need to calm down, stop growing and harden off to get ready for the winter cold. Some plants have already set next year’s buds.

Roses especially appreciate a bit of fertilizer now, encouraging them to bloom another round in October. To keep them blooming make a habit of pinching and pruning off old flowers. Always cut back to an outward facing branchlet with five leaves. There are hormones there that will cause a new rose to grow much sooner than if you cut to one with only three leaves. You can always cut lower on the stem if you need to control height.

Deadhead flowering annuals and perennials in the ground as often as you possibly can. Annuals like zinnias and cosmos will stop blooming if you allow them to go to seed. The same is true of repeat blooming perennials like dahlia, scabiosa, echinacea and lantana. Santa Barbara daisies will bloom late into winter if cut back now. These plants know they’re on this earth to reproduce. If they get a chance to set seed the show’s over, they’ve raised their family. Try to remove fading flowers regularly and you’ll be amply rewarded. If you want to start perennial flowers from seeds this is the time so that they’ll be mature enough to bloom next year.

Now through October, divide summer blooming perennials like agapanthus, coreopsis, daylilies and penstemons that are overgrown and not flowering well. You can also divide spring blooming perennials like candytuft, columbine, astilbe, bergenia and bleeding heart but sometimes they don’t bloom the first spring afterwards due to the energy they use re-establishing themselves. If you’re on a roll out in the garden, go for it now.

It’s still a little hot to plant cool season veggies starts in the ground. They appreciate conditions later in September when the soil is still warm but temps have cooled. It is OK to plant seeds of beets, carrots, spinach, arugula, mustard, leeks, onions, peas, radishes and turnips.

If you aren’t going to grow vegetables in the garden this fall consider planting a cover crop like crimson clover after you’ve harvested your summer vegetables.
It’s never too soon to start planning for erosion control in those areas that caused you problems during last spring’s storms.

Cut back berries vines that have produced fruit. Canes of the current season should be trained in their place.

Spider mites are especially prolific during hot, dry weather. Sometimes you don’t even know how bad the infestation is until all your leaves are pale with stippling. Periodically rinse dust and dirt off leaves with water. Spray the undersides of infected leaves with organics like insecticidal soap switching to neem oil if they build up a resistance to one of the pesticides.

Now that you’ve taken care of your chores reward yourself by adding perennials to your garden for color in late summer through fall. Take a look at the garden areas that aren’t working for you and replant. Good choices include aster, chrysanthemum, coreopsis, and gaillardia. Abutilon (Flowering Maple) come in so many colors that you probably need another one in your garden. Petite Pink gaura looks fabulous planted near the burgundy foliage of a loropetalum. Don’t overlook the color of other foliage plants like leucodtendron ‘Jester’ or Orange Libertia in the garden. A favorite ground cover that hummingbirds love is grevillea lanigera. Consider it for those hot areas.

One last to do: Make a journal entry celebrating the best things about your garden this year.

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