All posts by Jan Nelson

I am a landscape designer and consultant in the Santa Cruz mountains in California. I write a weekly gardening column for the Press Banner newspaper. I am also a Calif. Advanced Certified Nursery Professional and managed The Plantworks Nursery in Ben Lomond, Ca. for 20 years.

How the Health of Your Soil Affects You

“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

We are all familiar with the saying, “feed the soil, not the plant.” This is because plants do not grow independently. They grow in a partnership with micro and macro organisms including fungi, beneficial bacteria, micro arthropods, nematodes, insects and worms. We are just beginning to understand the complexity of soil biology. Soil is the foundation of agriculture including home gardening. When you maintain healthy soil, healthy plants will follow.

The biggest issue we gardeners face is the ongoing battle with soil. If yours is difficult to manage or unproductive you’ll be disappointed 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.

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 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 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 with1/4“ of compost and 2-3” 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.
• Use aerated compost tea
• Try to avoid walking on the root zone of plants. This kills fungi in the soil. Install stepping stones to preserve soil structure.

News You Can Use About Bees

In addition to native plants many common garden plants like dahlia provide nectar for bees.

A friend of mine lamented she didn’t have many bees in her garden yet. I reassured her they are out and about and will soon visit her garden. She was worried that our bee population was declining dramatically. And while it is true that bee populations have been affected by parasites, pesticides, habitat loss, invasive species, climate change and diseases there has been some progress on the legal front.

The Pollinator Protection Act bans over the counter sales of lawn and garden neonicoticoid (neonic) pesticides by 2025. This chemical is present in many systemic insecticides found in stores now. The law limits their use to trained professionals. Look these pesticides up at www.beyondpresticides.org. The bill also directs the California Department of Pesticide Regulation to complete a long overdue review of non-agricultural neonic uses.

In September, the California Supreme Court left in place a lower-court decision holding that bees are fish- at least for the purpose of protecting them under California’s endangered species law. Every little bit helps. The loss of bees has critical implications for food production and ecosystem health.

California is a vast domain when it comes to natural features and different soils. From hills and mountains to deserts, valleys and ocean bluffs, there are over 6000 plant species within our borders. Hundreds of these are showy and useful plants worthy of cultivation in our garden. Some, like ceanothus, have already been cultivated for a century or more, both here and abroad.

There are features of the California landscape that present a certain flavor and seasonal progression, quite distinct from that of the subtropics and year-round, moist forests that many traditional garden plants come from. Plants of hilly and mountainous areas are often found in rocky or sandy soils and require well-drained garden soils. Many plants of the chaparral have poor resistance to the root pathogens that thrive in a warm, moist soil and may not tolerate typical garden style irrigation in summer.

Matching or creating the right conditions is the key to success to grow California natives. Planting on a raised mound or berm, for instance, is one way to drain water away from sensitive crowns. Knowing where in California a given native plant comes from can help you make the right decisions.

That being said there are many natives with an amazing broad tolerance of different conditions. Toyon (Heteromeles arbutifolia) grows in both sandy and clay soils as does yarrow (Achillea millifolium) which is also a good cut flower. Carex grass and Seaside daisy (Erigeron glaucus) also do well in most soils.

If you garden in clay soils, good native shrubs are Western redbud, manzanita, spicebush, bush anemone, ceanothus, garrya, Pacific wax myrtle, Western mock orange, blue elderberry, mahonia, California wild rose and snowberry. Native perennials for clay soil include coral bells, sticky monkeyflower (a good cut flower), salvias, deer grass, rubus and Dutchman’s pipe vine.

Sandy conditions require California natives that are decidedly drought tolerant. You may already grow many of our manzanitas and ceanothus. But do you also have lupine, lavatera, coffeeberry, buckwheat, fuchsia-flowering gooseberry, purple sage, wallflower or the beautiful Douglas iris?

Then there are the folks that live in the shade. Native plants from canyons and riparian areas will do well in your garden. They require some summer watering but that’s all. Native shrubs that tolerate bright shade are manzanita, spicebush, bush anemone, ceanothus, mahonia, Pacific wax myrtle, any of the ribes, wild rose, snowberry and huckleberry. Perennials for color are columbine, Western bleeding heart, California. fuchsia, Douglas iris and coral bells.

Where ever you garden provide food and nectar for our winged friends.

Bees in the Garden

This American Painted Lady Butterly and the Yellow-faced bumblebees both enjoy the nectar of these dianthus.

You can hear them a long way before you see them. I’m talking about the hundreds of honey bees feasting on the nectar of the Flowering Plum blossoms. I confess I don’t know a lot about keeping bees. I even had to look up what a nuc was when offered as a pre-order from Mountain Feed in Ben Lomond. BTW- a nuc is a small, fully functioning hive. It consists of 5 deep frames containing all stages of brood and live adult bees along with a young well-bred queen. However, I do know how to attract all types of bees to the garden and here are some tips and interesting information about the bees in our area.

There are 1600 species of native bees in Santa Cruz county. They are solely responsible for pollinating many of our native plants. Being solitary they do not make a hive but make nests underground or live in wood, one female per nesting hole and she lays her eggs there. Leaving areas in your garden near flowering plants un-mulched helps her find a nesting hole. The hard working females mate, make nests, collect pollen for their young and lay eggs. Males live to mate and only pollinate inadvertently when they visit flowers for nectar to fuel their flight.

Common native bees in our area are the yellow-faced bumble bee and the long-horned bee which has stripes a little like a yellow jacket. The hard working bumble bee is easy to identify from its bight yellow facial hair and yellow bands on their backs and abdomens. Female bumble bees’ hind legs widen to form pollen baskets often filled with bright yellow, moistened pollen pellets.

The Long-horned native bee gets their name from the long antennae of the males although the females do not have this. Males may be seen by day jostling for female attention above a patch of blooming plants while the females are collecting pollen. Only the females have branched hairs on their legs for carrying pollen.

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 our area 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.

Common garden plants that can attract bees and provide pollen in your landscape and vegetable garden are herbs such as African blue basil, bee balm, 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, aster, coreopsis, sunflowers, monarda, aster, butterfly bush, sweet alyssum, alstroemeria, red hot poker, gloriosa daisy, verbena, scabiosa, coneflower and echium also attract bees of all types.

The higher temperatures that come with climate change can affect a bee’s ability to detect a flower’s pollen. A flowers scent is what tells a bee that nectar is present. If the weather gets too hot the plant will spend less energy on producing fragrance and just try to survive. When flowers stop emanating these enticing smells, some bees have a tough time finding food and may abandon certain area. Studies have shown that warming climates already have affected our central coast bumblebee population during the past 30 years especially the California bumblebee.

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

Honeybees and native bees need help to survive and we’re the ones to give it. Besides planting nectar and pollen sources you can help by buying local honey which support beekeepers. Use only organic pesticides and avoid applying during mid-day hours when honey bees and pollinators are most likely to be out foraging for nectar and pollen on flowering plants and only then if you can’t control a pest with any other methods including Pest Management techniques.

Help save the bees. Next week I’ll provide more interesting facts about bees and what attracts them to the garden.