What’s Sheet Mulching?

Can you believe this yard was solid ivy, blackberry and vinca not that long ago?

Boy, was I impressed. Not long ago I was at a garden to consult with a new client on some upgrades they envisioned for their property. I love to meet new gardeners and give them “my two cents worth”. Well this homeowner had Googled how to get rid of her entire yard full of ivy. It also had a little vinca and blackberry thrown in just to make it interesting. Her success is story of inspiration. If she can do it so can you.

Because the ground is still moist from recent rains and summer is coming, this is the perfect time to get rid of an old lawn or invasive ground covers.

This simple technique eliminates a lawn or invasive ground covers by smothering them with layers of compost and renewable materials. Here’s how to do it:

  1. Mow the lawn down to 1-2 inches, leave the clippings in place and soak with a hose if the soil is dry. If dealing
    with ivy, blackberries or vinca remove as much of the top growth as you can.
  2. Flag the locations of sprinkler heads you will be keeping for your new plantings and cap off the ones you won’t
    need if there is an irrigation system in this area.
  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 of soil along these edges and back about 8-12 inches so that the new mulch doesn’t slide off into the sidewalk. This is not necessary with ivy.
  4. Put down 2-3 layers of newspaper or one layer of cardboard overlapping the edges by 6-8 inches 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 that will break down quicker. Don’t use plastic sheeting because water and air cannot penetrate it.
  5. Add a 3 inch layer of mulch such as wood 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 inches of mulch to smother them.
  6. Water thoroughly.

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 inches 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.

This yard use to have an old lawn before it was sheet mulched away.

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.

Why Mulch?

You can get results like this garden with organic mulch.

Mulch is not a very exciting subject but it sure is important to the health and productivity of your garden.

It’s great that everyone has accepted the value of covering the soil with organic mulch. Organic mulches- such as bark chips, treated sawdust, straw or even grass clippings keep plant roots cool, encourage earthworms and other beneficial organisms, conserve soil moisture, combat weed growth and protect the soil from erosion.

But is there an organic mulch that is better than another?

There are many types of mulch available. Nurseries sell different types of mulch in bags, building supply yards carry everything from bark nuggets in different sizes to treated sawdust to chipped wood and even shredded redwood bark. Shredded redwood bark, also called gorilla hair, does nothing for the health of your soil, however. If you have a very steep slope you may have to go with this type of mulch but that’s the only time I can recommend it. It will cling to a hillside without washing down in winter rains but treated sawdust would also work for this type of terrain and is much better for soil health.

Of all the types of organic mulches out there, recent studies have shown that ramial bark chips are one of the best mulches to improve soil health. Ramial chips come from trees and brush with branches up to about 3 inches in diameter- with or without leaves. These chips contain a high percentage of thin young bark and young wood. This is what makes them so valuable to the garden. Young wood is a trees factory for producing protein, glucose, fructose, lignin and polysaccharides. It’s an important source of nutrients for living things at all levels according to a study by soil scientists, G.Lemieux and R.A.Lapointe. You can obtain these kind of chips free from tree trimming companies who are probably working nearby chipping roadside brush for PG&E. Any disease in the chips doesn’t transfer to healthy plant roots, as long as you don’t dig the chips into the soil. You can also buy clean chips from landscape supply yards or in convenient bags from nurseries.

Newly installed, this garden will thrive with organic mulch.

Make sure you get fresh mulch spread over your garden plants soon. It’s that time of year to mulch existing perennials, shrubs and trees.Besides the mulches mentioned above a little chicken manure is good worked into the veggie garden but composted horse manure works better as a mulch for the rest of the garden. Chicken manure is high in phosphates and too much can inhibit beneficial microbes in the soil. It also feeds the weeds. They love it. A better method would be to cover a layer of compost or composted horse or steer manure with a thick 4 inch layer of wood chips.

You’ll be amazed at the difference in your garden this season. A mulched garden is a happy garden. And if you have ivy, berries or vinca you want to eradicate, sheet mulching is the way to go. Next week I’ll go over the basics and share some success stories.

Garden Inspiration at the Gamble Garden Tour

Picture your friends and family around this inviting fire pit.

Looking at your yard and thinking “This year I’m finally going to make some changes and enjoy my garden more.”? Take my advice: go on a garden tour for inspiration. Even a visit to a neighbor’s beautiful garden will work to get your creative juices going and motivate you. I do have to say that the gardens I visited recently in Palo Alto were spectacular. Definitely “the garden of my dreams” and I may just have to practice what I preach in my own little space.

While some of the gardens were clearly out of my price range – this was Palo Alto remember – there were elements from every one that I could imagine in a regular garden around here.

Everybody’s garden looks the best in the spring. Plants are full of new, healthy growth and the heat of summer has not yet descended. Early flowering plants are at their peak and those that wait until summer to flower so that their nectar will attract hummingbirds, butterflies and bees are patiently awaiting their time in the sun. It’s a glorious time in the garden.

This strip between sidewalk and street is solved here with succulents.

Because The Gamble Garden Spring Tour is a walking tour I got as many ideas from the gardens featured as I did passing by the front yards of the other houses. This is the neighborhood where Steve Jobs used to live.
The theme of the garden tour, Garden are for Living, came through loud and clear in each of the gardens. Many featured sustainable features such as a decomposed granite patio, poured in place concrete pavers, corten steel raised beds and path edging and dry laid flagstone paths. Edibles were included in every garden- from a grape-covered pergola to a cleverly designed raised veggie bed complete with steel corners and banding and lighting for evening dinner harvesting.

While walking the neighborhood a low water use plant combination of ornamental olive trees under-planted with rosemary and Iceberg roses complemented one Mediterranean style home. Another garden nearby featured a rustic fence made from fallen tree branches. I must have taken a hundred pictures to remind me of all the great design ideas I saw that day. The gardens were very approachable. Most are maintained mostly by the homeowners.

Many of us have meandering paths in our gardens separating the different garden rooms. The elements of garden design, like arrangement of paths, planting beds and open spaces, shape your garden. Your eye is drawn along a path through a garden. The plantings along the sides serve to frame but it’s the style of the path itself that enhances your experience in the garden. Some of the paths can be gravel, some walkable ground covers with pavers, some flagstone. All draw the visitor deeper into the garden to explore and linger at each spot.

Over the years I have gotten lots of inspiration from other gardens and tours. Valley Churches has held several fundraiser garden tours. I remember how fun it was to see the Enchanted Gardens of the Valley which was in San Lorenzo Valley one year, in Scotts Valley only a few years ago and one in Bonny Doon quite a while ago. On each of these tours I knew some of the garden owners and had spent time in each. Also I’ve gotten inspiration from visiting Camp Joy and everybody loves Filoli Gardens as well as Hikone Garden in Saratoga.

So go outside in your own garden and imagine the changes – big and small – that would make it spectacular.

Fragrance in the Garden

Is everything fragrant that’s blooming now or is it just me? Does Mother Nature have a card up her sleeve to insure pollinators find nectar thereby ensuring plant propagation or is it mostly spring fever on my part? What makes flowers fragrant anyway?

Fragrance in flowers is nature’s ways of encouraging pollination. Just as it draws you to take a deeper whiff, it lures insects to blossoms hidden by leaves. Some flowers are fragrant only at night and attract night-flying pollinators like moths, while others are more fragrant during the day and attract insects like bees and butterflies.

The fragrance itself comes from essential oils called attars that vaporize easily and infuse the air with their scents.
Aroma chemistry is complex and the smell of any flower comes from more than a single chemical compound. These molecules are present in different combinations in different plants, but often they are markedly similar which is why there are irises that smell like grapes and roses that smell like licorice.

Our noses can detect those chemical compounds that have a major impact on the aroma. Often a particular molecule will make a large contribution. Some roses, for instance, derive their scent from rose oxide and others from beta-damascenome or rose ketones. These molecules are detectable by our noses at very, very low concentrations. Carnations, violets, lilies, chrysanthemums, hyacinth- all have their own set of compounds that contribute to their scent.

It’s interesting also that as we become accustomed to the same smells our brain phases them out. A compound called ionones, found in violets and rose oil, can essentially short-circuit our sense of smell, binding to the receptors. This shut down is only temporary and the ionones can soon be detected again and registered as a new smell.

The word fragrance comes from the 17th century French word fragrantia, meaning sweet smell. A garden’s fragrance can be as unforgettable as its appearance. The scent of a particular flower can make you remember past times and places. Plant them along a garden path to enjoy as you stroll, in containers to scent a deck or patio or locate them beneath a window and let their aroma drift indoors.

Old fashion lilacs are still blooming in gardens. Nothing ways “spring” like the legendary scent of these shrubs. Give them a spot in full sun with enough room for them to spread 6 feet wide. While most plants accept slightly acidic soils, lilacs are an exception. Dig lime into your soil at planting and side dress yearly if your soil is acidic.

Place sweet-smelling plants where you can enjoy them throughout the season. The potency of flower scents varies greatly, so consider the strength of a fragrance when deciding where to put a plant. Subtle fragrances such as sweet pea, lemon verbena, scented geranium and chocolate cosmos smell wonderful right outside the back door. Add stronger scents by your deck, pool, spa, dining area or gazebo. Stargazer lilies, jasmine, lilacs, daphne, citrus and peonies will make you want to stay awhile.

Several easy-to-grow shrubs have fragrant flowers as an added bonus. Mexican Orange (choisya ternata) blooms most of the year. Pittosporum eugenoides, tenuifolium and tobira all have tiny blossoms that smell like oranges. too. The tiny flower cluster of Fragrant Olive (osmanthus fragrans) have a delicate apricot fragrance.

Other fragrant plants include California native Philadelphus lewisii (Wild Mock Orange). Calycanthus occidentals (Spice Bush) is native to our Central and Northern California mountains. Their fragrant burgundy flowers smell like red wine. Ribes viburnifolium, carpenteria californica and rosa californica are mildly scented, too.

In spring there may be nothing quite as spectacular as a wisteria vine, loaded with fragrant purple, pink, blue or white flower clusters, covering an arbor or pergola. Pink jasmine is another vigorous vine with intensely fragrant flowers as is Evergreen Clematis.

Plant for fragrance. It’s your reward for all the care and tending you give your garden.

Spring is Busting Out All Over

Every spring when the dogwoods, lilac and wisteria bloom I get excited. Not having room myself for these beauties I visit friend’s gardens often. Seems everything is flowering now- lavender, salvia, protea, ceanothus, lily-of-the-valley shrub, bleeding hearts, coral bells, grevillea, camellia, abutilon and more. Here are some of my favorites from the past week.

A hike at Quail Hollow is always a treat. The native bleeding heart ground cover (dicentra formosa) greeted me with hundreds of flowers as I started to hike. Along the trail the white Pacific Coast Iris (iris fernaldii) stood out alongside the sky lupine. Stunning Silver Bush lupine made quite the show in the dry, sandy soil.

Later in the week I admired a Variegated Star of Madeira (echium candicans) at my friend Joy’s house. Because she’s a landscape designer she had planted in a spot that receives little water while attracting bees and butterflies and controlling erosion on the hillside. It was breathtaking being in full bloom alongside a Julia Phelps ceanothus with a few California poppies thrown in for color.

The next garden I visited belonged also to another fellow designer. Cathleen’s piece of paradise always has something in bloom and this day did not disappoint. Lilacs scented the air. She has some in several colors from classic lilac to pink to white. Her hellebores were still blooming and she has quite a collection now including the varieties with double blossoms as well as upward facing flowers. I’m waiting for her Ghostly Princess Spanish lavender to start blooming. Last year it was gorgeous.

You can’t drive anywhere these days without encountering dogwoods and wisteria in full bloom. Wisteria are long lived and can grow quite large as you probably know if you have one. When you see one growing up a redwood and it’s reached over 50 feet it’s impressive. There is one that is smaller and easier to maintain. Perfect for smaller spaces Amethyst Falls blooms at an early age with lightly fragrant purple racemes weeping gracefully downward. You can use it in a container on the porch or patio or train it up an arbor or trellis. It repeat blooms lightly in the summer. Twining stems quickly reach 8 to 10 feet.

I love white dogwoods. Cherokee Princess just pop with their snow white blooms in our mixed forest. But it’s the pink ones that get to me. There is a big Eastern dogwood on the road I used to live on in Bonny Doon that survived the fire. It doesn’t get any water anymore but still manages to bloom. Talk about being a survivor. I really like the rose red flowers of the Cherokee Brave variety. After the beautiful flowers in the spring it gets vibrant red berries that feed the birds. In the fall the leaves turn crimson.

Dogwoods attract a variety of wildlife. All sorts of critters use this tree for food and shelter. The giant silk moth and several species of butterflies favor dogwoods as host plants. The spring flowers provide nectar to bees and other pollinating insects. Robin and sparrow are just two of the bird species that build nests on the horizontal branches and many others seek shelter in the leaves. The high calcium, high fat, fleshy red fruits are eaten by 35 species of birds including titmice, juncos and waxwings.

And remember that dogwood are a good tree choice for the allergy sufferer as their pollen is not wind borne. Their showy flowers, which are actually bracts, are pollinated by insects. Their pollen is large and heavy, sticking to insects rather than becoming airborne and leading to sneezing, runny noses and watery eyes.

This is turning out to be an incredible spring. Get out and enjoy it.

Things to Do on Earth Day 2024

Little kids like Grace an appreciate tiny flowers and seeds pods in the garden.

If the partial eclipse had fallen on Earth Day it would have been the perfect trifecta as Jupiter and Venus were also visible that day. Still it was fun to watch the moon cover part of the sun and reflect on our planet and what we can do to help. Earth Day is April 22nd. Here’s what we can do to keep our planet healthy.

This year Earth Day is focusing on our Planet vs Plastics. Plastic pollution is all around us. On Earth Day we celebrate the natural beauty of our planet and are reminded to be conscientious about the products we use, the waste we produce and to keep sustainability in mind when we make choices.

Earth day is a day of education about environmental issues. Celebrate it in your own backyard by being outside. It’s your own personal outdoor living room – a safe place for pets and kids to play. Just get outside, maybe trim some shrubs, plant something for the birds and pollinators. When you become a steward of your own yard, you are helping to preserve your own corner of the ecosystem. Our connection to the earth is one of the most valuable lessons we can share with our children.

I get to spend time with 4 year old Grace who used to live next door. She’s able to name the chickadee, nuthatch, Stellar’s jay, junco and the hummingbirds who are all frequent visitors. In a garden, children can breathe fresh air, discover bugs and watch things grow. And, of course, a garden offers kids and everyone else fresh, tasty homegrown food. What better place for kids to play than in a place where they can use their hands and connect with the earth? Where else can they make a plan for a plot of land and learn the lessons of hope and wonder, suspense and patience and even success and failure? In a garden you can have conversations about life and even death in a way that doesn’t seem so sad. Grace tells me that my dog Sherman is “in the stars.” She accepts that as part of her world.

Finding things to do in the garden is easy. You probably already have some edible flowers in your garden. Flowers like tuberous begonias, calendulas, carnations and marigolds are all edible. Last year Grace & I planted zinnias for the Swallowtail butterflies. This year will be cosmos to attract more butterflies. Fragrant flowers and herbs are fun for us to smell. She noticed that some of the yellow primroses were fragrant and I have lemon verbena, peppermint, spearmint to enjoy also.

Kid friendly gardens should not contain plants that are poisonous. Sounds like a no brainer but even some of our common natives like the berries of snowberry and the leaves of Western azalea are poisonous. Non-toxic plants include abelia, abutilon, liriope, butterfly bush, Hens and Chicks, columbine, coneflowers, coreopsis and black-eyed Susan. Better to check the poison control website if in doubt. http://www.calpoison.org and search “plants”.

To share one’s excitement and knowledge of the outdoor world with a child is fun and rewarding. The wonder on a young person’s face as they discover a swallowtail butterfly, a flower just starting to open or a bird feeding in the garden is priceless. And be sure to leave some time after a busy day out in the garden for kids to draw what they’ve enjoyed outside.

Get a kid into gardening and nature and they’ll be good stewards of the land for a lifetime. Plus you’ll have a lot of fun in the process.

So plant a tree, clean up litter, do something in the garden, hike in the woods, enjoy a walk among the wildflowers and just be in contact with the soil, breathe fresh air and think about ways to reduce your use of plastic.

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