Category Archives: sustainable gardening

What’s in your Soil?

“The soil is made of butterfly wings, dinosaur teeth, pumpkin seeds, lizard skins, and fallen leaves.
  Put your hands in the soil and touch yesterday, and all that will be left of tomorrow shall return
  so that new life can celebrate this day.”  -Betty Peck

Soil makes all the difference to the plants you grow. The biggest issue we gardeners face is the ongoing battle with soil. If yours is difficult to manage or just plain unproductive you’ll be disappointed like me with the performance of many of the plants you put in the ground. Even tough plants like California natives have soil preferences and they are not always what’s in your garden.

Low water-use plant responding to fertile soil

We live on ancient sea cliffs.  Soils in Bonny Doon and Scotts Valley consist of shallow, excessively drained weathered sandstone and shale. Felton soils were formed from shale, sandstone or mica schist. Those in Ben Lomond and Boulder Creek had their beginnings from weathered sandstone or granite. Although these provide the necessary mineral component of our soil. organic matter or humus from decayed plant and animal material are necessary also for fertility.

Here’s why improving your soil will make a difference to the health of your plants.

Good soil-with both organic matter and minerals-helps plants grow by forming the food supply for soil bacteria that help make food available for plant growth. Most of a plants energy goes to producing substances that drip out through the roots to attract bacteria and fungi. These in turn attract good nematodes and protozoa to the root zone. The protozoa eat bacteria and the nematodes eat not only the bacteria but also fungi and other nematodes to get carbon. What they don’t need they expel and this feeds the roots much like earthworm castings.

Down in the soil, if a plant needs different foods it can change what is secretes. Different substances will attract different bacteria, fungi, nematodes and protozoa. This huge diversity of soil biota helps the good guys keep the bad guys in check.

A common way to destroy the microbiology of the soil is to add salts in the

Collection of perennials one year after planting in amended soil.

form or non-organic fertilizers. The salts kill the bacteria and fungi by dehydrating them. Then the plant can’t feed itself and becomes dependent on its fertilizer fix. Without the good bacteria and fungi in the soil other parts of the food chain start dying off as well.

The soil food web is also responsible for soil structure. Bacteria create slime that glue soil particles together. Fungi weave threads to create larger soil particles. Worms and insects distribute bacteria and fungal spores throughout the soil and create pathways for air and water.

What can you do to bring your soil back to life?
• Mulch around perennials, shrubs and trees with 2-3” of compost, wood chips or other organic mulch.
• Apply mycorrhizal fungi, especially in a new garden that’s been rototilled or chemically fertilized. You can find this in most organic fertilizers and some organic potting soils.
• Try to avoid walking on the root zone of plants. This kills fungi in the soil. Install stepping stones to preserve soil structure.

Feed your soil- not your plants.

Sheet Mulch Away that Old Lawn

Replacing that water guzzling lawn or dramatically reducing the size is a good place to start conserving water and is easier than you think. If you’ve been paralyzed with the thought of digging out and hauling away hundreds of square feet of heavy sod or using dangerous grass-killing chemicals, sheet mulching is the method for you.

Sheet mulching in progress

This simple technique eliminates the lawn by smothering it with layers of compost and renewable materials. Here’s how to do it:

  1. Mow the lawn down to 1-2”, leave the clippings in place and soak with a hose.
  2. Flag the locations of sprinkler heads you will be keeping for your new plantings and cap off the ones you won’t need.
  3. Add an inch of compost to speed up the decay of the grass. If your lawn borders a driveway, path or sidewalk you’ll have to remove about 3” inches deep of soil along these edges and back 8-12” so that the new mulch doesn’t slide off into the sidewalk.
  4. Put down 2-3 layers of newspaper or one layer of cardboard overlapping the edges by 6-8” to prevent regrowth at the edges. You can buy recycled cardboard in rolls for larger projects or find your own at appliance or bicycle stores. Wet the cardboard or newspapers to keep them in place as you go along. It’s best to use cardboard or newspaper thatwill break down quicker. Don’t use plastic sheeting because water and air cannot penetrate it.
  5. Add a 3” layer of mulch such as bark chips from a tree trimming company. You can use compost, straw or shredded plant material. If you have Bermuda grass or other weeds like oxalis you will need to layer about 8” of mulch to smother them.
  6. Water thoroughly.
Plants installed immediately after sheet mulching

If you can wait a month or more to let the decomposition process get going so much the better. If you just can’t wait you can begin planting now by scraping away the mulch and poking a hole in the cardboard or newspaper where the plant is to go. Then add some compost to help the new plant become established. Be sure to plant high enough to prevent crown rot and keep the mulch a couple inches away from the stem. The top of the root ball should be 1-2” above the soil and just below the mulch.

Modify the sprinkler to drip and remember to adjust your irrigation system run times to accommodate your new plantings.

This is a basic “lasagna” method for lawn removal. If you are planning to replant with water smart grasses you would choose finer composted mulch instead of bark chips. Either way the process works on the same concept as a compost pile. As the lawn dies from lack of light, it decomposes with the activity of beneficial worms, insects and microorganisms coming up from the soil and doing their job to break down the nitrogen and carbon in the sheet-mulch layers. It’s a win-win situation for the environment and your water bill.

One year after lawn removal by sheet mulching

Water conservation starts with losing or reducing the thirsty traditional lawn and reducing irrigation. Transform your landscape into a resilient garden that not only saves water but acts to build the earth into a living sponge that harnesses rainwater and replenishes the aquifer at the same time. Attracting wildlife to your new beautiful garden is a bonus.

Be sure to apply for your rebates and have your lawn inspected, even if it’s dead, before you start.

Bees- Pollinators for a Bountiful Harvest

Pollination or the transfer of pollen in and between flowers of the same species leads to fertilization and successful seed and fruit production in plants. Pollen can be carried from flower to flower by pollinating animals such as birds, bees, bats, moths, beetles or by the wind but bees pollinate approximately 1000 plants worldwide including apples, blueberries, chocolate, coffee, melons, peaches, potatoes, pumpkins, vanilla, almonds and tequila. Clearly we need our bees- both native bees and honeybees.

honey bee pollinating African blue basil- photo courtesy of Gaylon Morris

Honeybees aren’t native to the United States. The colonist brought them here in the 1600’s to pollinate apple trees and for their honey and wax for candles. They are loyal to the plants they feed on and that makes them valuable to farmers and orchard owners. It works this way. When a worker bee leaves a hive in search of food it will feed on on one type of flower- whichever type it tasted first on that trip. Unlike other insects that might go from a cucumber blossom to dandelion to squash flower the honeybee sticks to one thing. That way it picks up and deposits only one type of pollen making honeybees particularly efficient in pollinating crops.

We know that honeybees are having a hard time of it due to diseases, parasites and pesticides. Planting flowers that bees like can increase the chances of bees’ survival as will cultivating native plants, especially those that provide nectar and larval food for pollinators.

Bees eat two things: nectar which is loaded with sugar and is their main source of energy and pollen which provides proteins and fats. Some of the common native plants that are recommended for the ecological region of our California Coastal Chaparral, Forest and Shrub Province by the North American Pollinator Protection Campaign to attract bees of all types include yarrow, columbine, California poppy, coral bells, silver lupine, penstemon, ceanothus, toyon, big leaf maple, mahonia, monkey flower, buckwheat, western azalea and purple sage.

honey bee on echium wildpretii

Common garden plants that can attract bees to your landscape and vegetable garden are herbs such as African blue basil, oregano, mint, catnip and cat mint, borage, rosemary, chives, hyssop, dill, comfrey and fennel. Edibles that attract bees are blueberry, pumpkin, squash, sunflower, blackberry, hazelnut, artichoke, beans, cucumber and peas. Crabapple, iris, lavender, salvia, sunflowers, monarda, aster, butterfly bush, sweet alyssum, alstroemeria, red hot poker, gloriosa daisy, scabiosa, coneflower and echium also attract bees of all types.

In your own garden an abundant and healthy population of pollinators can improve fruit set, quality and size. Crops raised in California depends on both domestic honeybees and native bees for pollination of almond, blackberry, cucumber and artichoke crops.

We can all help honeybees and other pollinating animals by being more mindful of the way we tend our yards. Reduce the amount of lawn you have and plant natives and flowers that will attract them. Use organic pesticides carefully and only if absolutely necessary. Buy local honey and support beekeepers. Honeybees and other pollinators need help to survive and we’re the ones to provide it.

What is a Sustainable Landscape?

I have a bat house on my property although the bats haven’t taken to it yet. I understand the importance of bats and bat conservation in the environment. I incorporate many California native plants in my own landscape and continue to add them to gardens I design. I encourage bees and other pollinators by creating a sustainable habitat for them in my garden. I use my water wisely conserving our finite water supply. I use organic pest control only if necessary to protect our watersheds from chemical contamination. I feel I am on the right track of sustainability and stewardship of the environment. But can I do more?

Organic plant starts at Garden Faire

Last week I attended The Garden Faire held at Sky Park in Scotts Valley. As I walked around the exhibits and listened to interesting speakers all the while serenaded by world music I thought to myself how can one person put all this valuable information to use in their own lives and gardens? How can I live more in harmony with nature?

Apple tree display at Garden Faire

How can I sequester more carbon by my plants to store in the soil? How can I protect the biodiversity already in place in my mixed redwood forest environment? Even though I don’t have the right conditions to grow my own organic food can I buy from growers who use ecological process on their farms? What native plants around my own house can I eat?

You hear the word sustainability used to describe everything from flooring to roofing to landscaping but what exactly is a sustainable landscape?

Sustainable landscapes are so well adapted to their environment that they require little in maintenance. Choosing plants adapted to your garden size, type of soil and climate keeps watering and fertilizing to a sensible level and reduces pruning as plants grow to the size needed and stay there.

Urbanite retaining wall

Sustainable landscapes use recycled, salvaged, durable building materials whenever possible. They use mainly materials that are harvested locally and use imported stone as an accent. Sustainable landscapes try to reuse what you already have laying it out differently to look like a totally new landscape.

Sustainable landscapes clean the air and water. They increase on-site infiltration of rain water to reduce runoff and minimize the amount of contaminants washed into the watershed and the bay. By keeping water onsite it can move into the soil where organisms breakdown pollutants and naturally filter them out before the water reaches groundwater or our waterways.

Sustainable landscapes conserve water by installing and

Swallowtail feeding on butterfly bush

maintaining high efficiency watering systems making every drop of irrigation water count. They create drought resistant soils by adding compost and mulch. They group plants by watering needs to irrigate them more efficiently.

Sustainable landscapes restore habitats by attracting native pollinators, beneficial insects and other organisms that reduce the need for pesticides. A sustainable landscape restores natural areas on the outskirts of your landscape to diversify your plant community.

Sustainable landscapes are responsive to the environment, re-generative, energy efficient and can actively contribute to the development of healthy communities.

How to Save Water & Have a Beautiful Garden

There was enough rainfall over the winter season for the California State Water Resources Control Board to modify their Emergency Water Conservation Regulations. On May 18th, 2016 it was adopted to recognize persistent yet less severe drought conditions throughout California and require local agencies to develop and implement conservation standards based on their particular circumstances.

Adelyn_ watering
My friend, Adelyn, helping to water container plants and edibles.

The new standard requires local water agencies to ensure a three-year supply of water assuming three more dry years in the future like the ones we experienced from 2012 to 2015. Water agencies that would face shortages under three additional dry years are required to meet a conservation standard equal to the amount of the shortage.

Makes sense to us who have long been on the band wagon to conserve water both indoors and out. Our local water districts have both kept their water conserving restrictions in place. Since up to 70% of summer water use comes from landscape irrigation it’s a good place to start.

Both San Lorenzo Valley Water District – and Scotts Valley Water Districts http://www.svwd.orgoffer many tips and incentives to conserve water. Using less water-intensive plants, there are lists on their websites of drought-tolerant plants and water smart grasses, as well as replacing lawns with drought tolerant or native plants and/or permeable landscape materials such as mulch, decomposed granite, permeable pavers are just some of the ways you can keep your yard looking beautiful and also be water efficient.

Rainbird Smart Irrigation controller

Rebate programs from local water districts offer several landscaping credits including sprinkler to drip irrigation conversion credit, weather-based irrigation controller credit, replacement credit for converting an existing lawn to water-wise grasses, greywater laundry-to-landscape irrigation conversion, rainwater catchment and downspout diversion. Both districts have guidelines and procedures to apply for the rebates on their websites.

Additional rebates from the California State Department of Water Resources are available to single-family residences for lawn replacement. This rebate application is separate from the local water District’s and you need to go online and follow the state’s guidelines in order to be eligible for these additional funds. See for the details.

Plants with similar water needs = hydrozoning

The fun part begins when you redesign the area where you took out the lawn or modify the plantings in other beds to include same water use plants. It doesn’t make much sense if you have some plants that require more water than the others in the same bed. You have to water to the highest water use plant to keep everybody happy.

Hydrozoning is the practice of clustering together plants with similar water requirements to conserve water. A planting design where plants are grouped by water needs improves efficiency and plant health by avoiding overwatering or underwatering. As you move farther away from the water source your plantings should require less water.

Now is the time before it gets hot to look at your irrigation system, plant choices and rebate options to save water and money and recharge our aquifers.

Climate Smart Plants for the Garden

Climate smart verbena lilacina with blue oat grass

All this talk about “drought tolerant” plants or “water smart” plants is misleading in some ways. What really matters for the success of a plant in your garden is that they are climate smart. You can call the new California garden climate tolerant or climate adapted but it all comes down to the same thing. The plants you choose to grow in your garden should be able to naturally tolerate periods of lower than average water. This doesn’t mean no water during extremely long dry periods. No plant can live without water.

I have two books that I look to for plant ideas when called upon to design a garden in our area. This first was published by East Bay MUD in 2004 and is called ‘Plants and Landscapes for Summer-Dry Climates’. The other book I refer to regularly for ideas and information is ‘California Native Plants for the Garden’. Both are invaluable in these times of water conservation. One of the best tips each of them offer is to garden where you live.

Philadelphus lewesii near Felton Covered Bridge.

All of us live in a summer-dry climate. Summer-dry gardens are naturally dry for long periods. Knowing which type of plant community you live in can make the difference between success and failure in your garden. Choose the right plant for the right place whether it’s a California native from an area with similar soil and exposure or a plant from another Mediterranean-like climate with growing conditions like yours.

Plant communities have evolved over time with geologic changes in climate, topography and soils. We have several district areas here- mixed evergreen forest, redwood forest, chaparral and sandhills.

If you live in a mixed evergreen forest you garden with trees like coast live oak, tan oak, madrone, bay and buckeye. Understory plants include ceanothus, coffeeberry, hazel and poison oak. Your soil contains serpentine and granite. Many other unthirsty plants like salvias, lavender, santolina, society garlic, giant feather grass, rosemary and rockrose do well here. California natives such as western mock orange (philadelphus lewisii), wild ginger and western sword ferns grow here also.

Iris douglasiana (Pacific Coast Iris)

Mixed evergreen forest may also be found along canyon bottoms near streams where big leaf maple, white alder, cottonwood, and western sycamore trees grow. Most plant here grow lush in this deep soil. If you are looking to add something new to your garden here consider giant chain fern, aquilegia, dicentra, Pacific Coast iris and fuchsia-flowering gooseberry.

Chaparral areas are the hottest, driest slopes of these mountains. Dense thickets of manzanita, coyote brush, chamise, coffeeberry, ceanothus, monkey flower and sage are native here. These plants are adapted to little water and often have tiny, thick, waxy, light green or grayish leaves. Soils tend to be rocky and shallow with overlaying rock or a subsoil that is mostly clay. Plants here need to have an extensive root system that reaches widely and deeply for water. If you live here a classic combination would be the spring blooming western redbud and Julia Phelps or Dark Star ceanothus. The combination of magenta and electric blue flowers is unforgettable.

The sandhills near Quail Hollow and Bonny Doon around Martin Rd. are part of an ancient sandy sea floor that was uplifted, eroded and exposed. These sandy soils lack organic matter and nutrients and their white color magnifies the temperature of the summer sun. Unique, native plants like silverleaf manzanita and Ben Lomond wallflower live here. Buckwheat and sticky monkey flower do well here. You might also try growing Lewisia, a pretty little plant native to northern California, thrives in sand and gravel soils with good drainage. This 8″ tall hardy perennial blooms from spring to early summer with extremely showy flower clusters in colors ranging from apricot to pink, rose and bright cherry red. Mulch them with gravel or crushed stone.

callistemon ‘Little John’

Remember right plant-right place. Don’t try to force nature although most gardens do look better with some summer water. Closer to the house we expect a fuller look. Combinations I’m going to try this season include leucospermum paired with blue echium or grey-leafed westringia planted with red-flowering callistemon ‘Little John’.