Design trends

Groundcover Ideas for a Changing World

Radiant manzanita grows well in partial shade.

Faced with what to use to keep down weeds when wood chips aren’t allowed? Well, you’re not alone. Although wood chip mulch is good for the health of your soil and your plants, it’s not recommended per new Cal Fire regulations within 30 feet of a structure. Years ago I had a request from a client faced with just this dilemma. Here are some of the ground covers I recommended for her garden and for others in the past.

Living ground covers add beauty to the garden while holding the soil in place and preventing erosion. They contribute to soil health by encouraging microorganisms. A garden wouldn’t thrive as well without groundcovers.

Groundcovers are like a fancy carpet in the garden.They add richness and beauty under trees and become the stars of the show in sunny spots. Groundcovers reduce maintenance by preventing weeds and reduce watering by acting as a living mulch.

When choosing ground covers, assess the conditions of the area you want to plant.

  • Is it in the sun or shade?
  • Is it a naturally moist area or dry?
  • Do you intend to water it or go with our natural cycle of wet in the winter and dry in the summer?

Matching the plant to the site conditions will ensure success.

When designing a plant layout consider whether you want a sweep of the same plant or a tapestry effect with a variety of plants. Using more than one type of plant allows you to work with foliage contrast adding pattern to the composition.

Common Snowberry or Creeping Snowberry (Symphoricarpos) will hold the soil on steep banks. This native tolerates poor soil, lower light and general neglect. Evergreen Currant (ribes viburnifolium) and creeping mahonia also tolerate shady conditions. All the low growing ceanothus are great choices for sunnier spots as are the manzanita groundcovers. Smaller natives that put down deep roots are yarrow, coast aster, California fuchsia, wild grape, mimulus, buckwheat, wild rose and salvia including ‘Bees Bliss’.

Low water-use non-native groundcovers like cistus salviifolius, grevillea lanigera, rosemany prostratus, rubus pentalabous, correa and sarcococca are also good low-water choices.

Remember when setting plants on a steep slope to arrange them in staggered rows. Make an individual terrace for each plant and create a basin or low spot behind each one – not around the stem – to catch water. Set the crown of the plant high so it won’t become saturated and rot after watering or rain and make sure mulch does not build up around the stem.

To create stunning combinations of ground cover plants. choose 5 or 6 styles and repeat them in small drifts to carry the eye through the composition. Add grasses for linear texture. Good candidates are Blue Oat grass, a non-spreading clumping grass with silver leaves. Carex elate ‘Bowles Golden’ is a spectacular evergreen ornamental grass and Carex tumulicola (Foothill sedge) is another good choice for a grass-like plant.

There are many more choices for groundcovers that grow in the shade. Stay tuned.
Take the opportunity to survey your garden for bare spaces that can come alive with added texture and color.

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.

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