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.
Design trends

Gardening Tips for Sandy Soil

Common in the Santa Cruz mountains, Bush Poppy bloom readily in sandy soils.

Many years ago I started writing a book about Gardening in the Santa Cruz Mountains. One of many interesting subjects I researched was the different soils we have here in the mountains. I don’t need to tell you if you garden in dense clay, serpentine soil or that sandy soil like being at the beach that our soils are challenging. That sandy soil? Well, it’s because we used to be a beach eons ago before the land rose up out of the sea. Here are some tips for those who live with sandy soil.

The distinct region of the Santa Cruz sandhills, with its gritty, well-drained soil, presents both opportunities and hurdles for gardeners. Here’s how to turn your sandy soil into a thriving garden?

Sandy soil is composed of larger particles compared to clay or loam, meaning it drains quickly and doesn’t retain nutrients well. This is not a death sentence for your garden. You can transform your terrain into a lush, productive garden with just a few steps.

Start by improving your soil’s structure. Organic matter is your best friend. Compost can really boost your soil’s
ability to retain moisture and nutrients. Regularly adding organic matter will gradually improve its texture and fertility. Do this every year. Cover crops, such as clover or fava beans, can be very beneficial. They not only add organic matter to the soil when turned under, they improve soil structure and even fix nitrogen, enriching the soil for your plants.

Low water use Fremontodenron grow well in sandy soils.

Choose plants that will thrive in sandy, well-drained soil. Native plants are good choices as they are adapted to our local conditions. I see Bush Poppy (dendromecon rigid ) thriving in the most inhospitable of places. Plants from the Mediterranean area and Australia are also good. Manzanita and ceanothus thrive in sandy soils. Rosemary, lavender and thyme do well in porous soil and are fragrant. Salvia, buckwheat, yarrow are easy to grow in sandy soils. Carrots, radishes and potatoes are ideal for sandy soils because they prefer loose, well-draining conditions. Be sure to provide plenty of organic matter and mulch to help retain moisture around your plants.

One of the main challenges with sandy soil is water retention. Water wisely, frequent, shallow watering won’t work here. Instead, water deeply and less often to encourage plants to develop deep root systems. Drip irrigation systems can be particularly effective, delivering water directly to the plant roots and reducing evaporation. Mulching is another critical practice. A thick layer of mulch helps retain soil moisture, suppresses weeds adding organic matter to the soil as it decomposes.

Because sandy soil doesn’t hold nutrients well, regular feeding is important. Organic fertilizers like compost tea, fish emulsion or seaweed extracts are great for providing a steady supply of nutrients. Slow-release granular fertilizer is also good.

The natural beauty and unique characteristics of the sandhills can be enhance by incorporating elements that blend with the landscape. Rock gardens, succulent beds and native grasses can create a stunning, low maintenance garden that harmonizes with the environment.

By understanding and working with its unique characteristics, you can cultivate a thriving garden even in the Santa Cruz sandhills.

Design trends

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.

Design trends

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.