Design trends

All About Soil

With happy soil your perennials will look like this

The calendar shows it’s spring. The longer days definitely say “spring.” And the weather couldn’t be more “spring-like”. But Im concerned about the soil in my small garden. Besides battling the gophers (what could they be finding to munch on down there?) my soil is dense and I need to make it more fertile. Here’s what I’m going to do to solve that problem.

Soil is an ecosystem made up of the living or that which was once alive and the abiotic which is made up of minerals, air and water. Soil texture is determined by the percentage of sand, silt and clay in the soil. Sandy soils are usually low nutrient, drain well, warm quickly and allow early cultivation and planting in the spring. Clay soils are the opposite.
Some soils are more beautiful than others but any soil can be radically improved with the addition of organic matter.

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 it 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.

Design trends

Fragrant Plants Blooming Now

Enjoy the fragrance of yellow primroses in your garden this spring.

I’m ready for spring. Those few warm spells have given me spring fever. Many plants blooming now are fragrant. Mother Nature encourages pollinators to find sweet nectar thereby ensuring plant propagation 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 scent. 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 small 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 other from beta-damascenome or rose ketones. These molecules are detectable by our noses at very low concentrations. Carnations, violets, lilacs, chrysanthemums, hyacinth- all have their own set of compounds that contribute to their particular 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, including the receptors. This shut down is only temporary and the ionones can then be detected again and registered as a new smell.

Blooming now since early winter, the pale yellow primroses fill the air with the sweetest scent. It’s only the yellow ones and not all shades of yellow that are fragrant but these make your head turn. The sweet alyssum I planted last fall on the deck is getting a run for the money in the fragrance department, too.

Many other spring bloomers are deliciously fragrant. Whether you’re planting edibles in the vegetable garden or containers on the deck, include plants that entice you to linger and enjoy their sweet scent.

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 will be blooming soon. Nothing says “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.

Looking for something in vanilla? Evergreen clematis vines make a great screen with 6 inch long, glossy leaves and creamy white, saucer shaped, vanilla-scented flower clusters. Provide study support for them to climb on. They are slow to start but race once established.

Fragrant shrubs that are easy to grow are Mexican Orange (choisya ternata) which blooms most of the year. Pittosporum eugenoides, tenuifolium and tobira all have tiny blossoms that also smell like oranges. The tiny flower cluster of Fragrant Olive (osmanthus fragrans) have a delicate apricot fragrance. Other fragrant shrubs include California native Philadelphus lewisii (Wild Mock Orange). Calycanthus occidentals (Spice Bush) is another 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.

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

Design trends

March Tasks in the Garden

California native, Red Flowering Currant is loved by hummingbirds.

A favorite survivor of the CZU fire is starting to bloom this week in my garden. Even though I had to remove the burned pot along with all the branches and roots, my red flowering currant ( ribes sanguineum) recovered to the delight of the hummingbirds. It’s growing in partial shade in a new pot here but would make a good shrub under oaks or other trees. The fruit is a dark purple oval berry which the birds love. This plants hosts several butterfly species. I’m so happy it survived.

This is what I recommend doing in your garden this month.

Weed – Besides enjoying all the early spring bloomers I’m doing a lot a weeding lately. This hopefully will be the last year I have to pull the thousands of self-sowing annual impatien balfourii which are loved by the hummingbirds all summer but geez, each plant produces hundred of viable seeds. Pull weeds regularly before they set seed. They pull out easily from moist soil. Weeds rob your plants of precious water. Think of weeding as free gym time.

Check drip systems for leaks or emitters clogged by dirt or earwigs. Flush sediment from filters and check screens for algae. You may need to add emitters if plants have grown significantly and move the emitters farther away from the crown of the plant and out closer to the feeder roots which are under the drip line.

Fertilize – Citrus may be looking yellow from lack of nitrogen and iron which is not absorbed easily during the cold season. Shrubs and fruit trees just emerging from dormancy are begging for their first meal of the season. Lawns -if you still have a small section- and ground covers begin their spring growth now also and benefit from a boost of organic nitrogen. Leave grass clippings on the lawn to shade the roots as it get warmer and as they break down they help feed it, too. Perennials benefit from both a fresh layer of compost and a light application of balanced fertilizer. They respond to the phosphorus from bone meal especially in the spring for root growth, stem sturdiness and flower development. Wait until azaleas, camellias and rhododendron have finished blooming and you see new leaf growth starting before feeding them.

Spread fresh compost around all your plants. Good soil is the secret to successful gardening. The first principle of organic gardening is to feed the soil and it will feed the plant. Remember that all gardening used to be organic. Layer 2-3″ of compost or mulch on top of the soil and let it slowly decompose and filter down into the earth. Bark nuggets do not increase your soil’s fertility like compost or wood chips do but they do conserve moisture and help keep weeds at bay.

Transplant any plants in the garden that have outgrown their space or are not with other plants requiring the same water usage. Now is a good time because plants are full of growth hormones and recover quickly from transplant shock. As you plant new additions to the garden add organic matter to the soil if it’s sandy. Organic matter enriches and allows it to hold water more efficiently. If your soil is sandy, organic matter will allow your soil to hold more moisture longer. If your soil tends toward clay, organic matter will loosen it and improve drainage. In fertile soil, plants grow deep roots, are hardier for cold, more resistant to disease and more drought tolerant. Organic matter such as compost, planting mix and well-rotted manure boosts nutrition and improves soil structure.

Check for aphids. They are out in full force sucking plant juices from the tender new leaves of everything from roses to hellebore to Japanese maples. A strong spray from the hose may be enough to dislodge them. If they still persist, you can spray organic insecticidal soap, neem oil or horticultural oil to kill them. As with all pesticide sprays, do this early in the morning or later when they are not in the sun. Be sure to test first to make sure the spray doesn’t burn the new growth and always mix according to the directions.

The most important to-do is to take time out and enjoy your garden and our beautiful surroundings. Those last few weeds will be there tomorrow but you’ll never get another today.

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