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.

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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

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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.

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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.
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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.

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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.

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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.

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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.