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.

A Private Arboretum in the Santa Cruz Mountains

Recently I had the honor to tour a remarkable garden in Scotts Valley. This horticulturalist calls himself a hillbilly gardener but he is no such thing. Some of his plants come from as far away as Oklahoma, Texas and Hawaii. What a thrill to see spring growth emerge from the new leaves of his unusual trees, flowering shrubs and perennials.

Our first stop was to admire his large collection of echium candicans or Pride of Madeira. These stately shrubs reach 5-6 ft tall and 6-10 ft wide so they make quite a show when the huge flower clusters are in full bloom. Being deer resistant and drought tolerant they are perfect for our mountain environment. The color of the spikes varied from pink to lilac, sapphire blue and purple. This gardener is resourceful. He got many of his seedlings along Hwy 17 where they had reseeded after being used as brush to stabilize the slopes after the ’89 earthquake. The bees were really happy visiting the hundreds of blossoms on the beautiful spring day that I was there.

Tucked under wild cherry trees collected in Texas, are second generation iris of dark purple and pure yellow. Originally from his grandmother’s garden in Virginia, these iris are descendants from a light blue variety and a pale yellowish-beige douglas iris.

This extraordinary gardener also has a huge wild rose from Missouri covered now with fragrant white flowers, a wild olive from Texas and a sand plum from Oklahoma.  There is a yucca about 4 ft tall that he and his brother started as cuttings when they were teenagers in Port Arthur, Texas. He is also the proud father of a couple of bald cypress complete with "knees". This tree of southern swamps and other low nutrient areas grows woody projections above the ground or water level to act as a structural support and stabilizer allowing them to resist very strong winds. Even hurricanes rarely overturn them.

A beautiful Canary Island palm, planted from a seedling in 1996 that he had nurtured in a gallon can, is now over 9 ft tall.  Akebia vines grow up oak trees, passiflora and white wisteria vines up redwoods, a yellow banksia rose rambles up into a madrone and madevillea laxa is happy growing up an oak, too. A willow-leafed hakea salicifolia, indigenous to New South Wales and Queensland, graces his entry with its tiny, white fragrant flowers.

Other trees this gardener loves include Causarina, native also to Australia, sugar pine, incense cedar, Western red cedar, deodar cedar, staghorn sumac and a maytens tree.  His mother in Pennsylvania taught him to plant his first garden at age 4 and he cherishes his Eastern white pines, pinus stroblis, and giant sequoias, three of which he grew from seed.

And I can’t forget his collection of salvias. The red flowers spike of salvia confertiflora bloom year round. The beautiful salvia mexicana will soon to be covered with rich, blue flowers. He also grows salvia chiapensis and a salvia-like plant native to Hawaii called salvia lepechinia. This deliciously scented plant will be covered soon with reddish lavender lipstick-like flowers adored by hummingbirds like all the salvias.

A new greenhouse where he has a small collection of orchids will soon house new seedlings that are sprouting in a germination station under lights. Of the many Hawaiian seeds he has collected are maile, a flowering plant that is probably the oldest and most popular material used in leis by early Hawaiians, milo- a chocolate and malt powder popular in many parts of the world, gossypium tomentosum, coral vines, hibiscus and the koa tree.

There were hundreds more cool plants I learned about and got to admire that day. I’ll be visiting this garden again and again for the next round of wonders. it’s a marvel.

 

The Mountain Gardener’s Hot Plant Picks for 2011

It’s not just another garden show, it’s the world renowned San Francisco Flower & Garden show and it was the perfect start to spring. Sure the show gardens are part theater and part reality but you can’t help but come away with inspiration, ideas and spring fever. One of my favorite parts is the display of new plant introductions from Western Horticultural Society. These are great plants destined to become favorites in the garden.  Well, I have my own Top 10 Hot Plants for 2011. These selections do not include California natives because Native Plant Week is coming up soon and I’ll focus on our valuable natives in an upcoming column.

I’m often asked for plant recommendations for our unique set of gardening conditions-extreme weather, heavy clay or sandy soil and limited water resources in the summer months. The following plants are easy to grow, have few or no problems with pests of diseases and posses valuable qualities such as color, fragrance, winter interest or support wildlife and beneficial insects. Try something new this year in your garden.

Grevillea lanigera ‘Coastal Gem’. This low spreading shrub grows 1 ft tall by 4-5 feet across and blooms year round with pink and white spidery flower clusters. Great for attracting nectar feeding birds and gophers don’t like their taste. Full sun, evergreen and drought tolerant -this is a great groundcover.

Kaleidescope abelia
This evergreen shrub is a kaleidescope of color as it’s name implies. Variegated foliage is bright yellow and green in spring, changing to golden yellow with bright oranges and fiery reds in fall. Its grown habit is densely compact and rounded. The beautiful foliage doesn’t scorch in the sun either.  It’s a beauty 2-3 ft tall and 3-4 feet wide. What more can you ask for?

Loropetalum Pipa’s Red
Also known as Fringe flower this shrub sports rich burgundy foliage in a fountain shape with tiered branches. Raspberry flower clusters are heaviest in the spring but some bloom is likely throughout the year.   I place this plant in the foreground where you can appreciate it’s graceful shape-looks great as an accent or in a raised bed.   The burgundy color can add color to a woodland garden and it even does well in a container on the patio.   You can prune it to any size but please don’t turn it into a tight ball and ruin it’s shape. Another plus is that it is not attractive to deer. 

Karl Foerster feather reed grass adds a vertical element to your summer and fall garden. It provides wonderful contrast among low shrubs and perennials. Named after the famous landscape architect and photographer with a love for all aspects of perennial plants, Karl Foerster  lived in Germany from 1874 to 1970. This grass won the 2001 Perennial Plant of the Year and although it’s not new on the market it’s an  easy to grow ornamental grass that won’t overpower your space.

Cordyline Electric Pink
This show stopper lives up to its high-voltage name. It surpasses other grass-like plants with boldly striped leaves of maroon and shocking pink. This well-behaved cordyline is clump-forming and reaches only 2-4 feet in height and width. Place in large mixed container or flower borders to instantly add an exciting look.

Pennisetum Fireworks
With arching leaves striped with white, green, burgundy and hot pink this grass is beautiful in the garden. Purple tassels rise above the foliage in late summer. The variegated pink striped blades of this grass are just as spectacular as the purple flower heads. Some gardens with clay soil and heavy frost in winter may need to grow this plant in a container for protection but it’s worth the extra effort.
 

Leaucadendron Safari sunset
Fiery red bracts on densely covered tall stems are sure to draw oohs and aahs. This is one of the most popular Leaucadendron available. It’s a vigorous, erect grower to over 8 feet tall and tough enough to handle frost and clay soils. The flower is actually an insignificant cone surrounded by large colorful bracts which are excellent for cut foliage harvesting.

Belinda’s Find red hook sedge
This red sedge is a two-tone delight of bright cherry red leaves with a green stripe running down the center.  Its loosely tufted, upright form grows 12" tall by 15" wide in part sun. Tiny bulrush-like flowers, from June to August,are elevated above the tidy, low growing evergreen clump. Use in the front of the border, in masses or mixed containers.

Euphorbia Diamond Frost blooms continuously with clouds of white flowers that float above finely textured apple-green foliage. This delicate looking perennial may be small in stature, reaching 12-18 " tall and wide, but is easy to grow and surprisingly tolerant of drought and heat. Combine this airy plant with bright colors for a dazzling border.

Phormium Jester is a New Zealand flax cultivar that grows to 3 feet making it a better fit in the garden than some of the larger phormiums. It can tolerate fairly dry conditions but looks best with occasional to regular irrigation. This strong color combination of green and pink doesn’t revert to the parent plants coloring. It’s hardy to 15-20 degrees. You might find this plant also listed as Jubilee.

 

Vines for the Santa Cruz Mountains

If you enjoy and beautiful blooms, you can have them both when you plant vines.  Vines use little space, add color to bare walls and fences, cover free-standing arbors, provide shade and extend the garden skyward.  Vines are amazing plants.
   
If your trees aren’t big enough to provide shade yet , vines on a pergola or lattice work can cool a west facing patio.  They can also block the wind making your garden more comfortable.   Vines with large, soft leaves can soften sounds that would otherwise bounce off hard surfaces.  Birds will love you for your vines.  They offer shelter for many species and nectar for others. 
   
Creating an outdoor room with vines can make your yard feel cozy.  They readily provide the walls to enclose the space.  Views from one part of the garden may be partially open, framed by vines or blocked entirely.  Shrubs can also be used to create garden rooms but vines form a thin living wall that is quickly established.  Creating boundaries with vines also adds vertical design elements to an otherwise flat landscape.
   
Hide something unattractive with a covering of vines. A dog house, old stump, or rock pile can become a pleasant view when covered with vines.  Disguising a concrete block retaining wall with a climbing hydrangea will reward you with a great show of flowers each spring. A native vine like Roger’s Red wild grape or Boston ivy will provide fall color on the same wall.
   
Planting vines in containers or planters on a deck, balcony or paved area can add beauty to these areas. Remember that large containers offer more root space than small ones and require less frequent watering and transplanting.  Vine need support for them to climb.  A small lattice structure or netting stretched between posts works well for vines such as clematis and pink jasmine.  The  structure doesn’t need to be in the container.
   
Combining vines can have twice the effect.  A classic combination is to plant a large flowering clematis like Jackmanii with a rambling rose.  I’ve seen these on arbors and split rail fences and the look is breathtaking.
   
For a vine with long lasting interest, try trumpet creeper which blooms from midsummer to early autumn. Hummingbirds love it. Growing in sun or shade, it can tolerate wet or dry conditions and is generally pest free.  Give it lots of space to grow. 
   
Climbing hydrangea has showy white spring flowers and bright yellow autumn color before the leaves fall.  During the winter months the peeling bark provides interest.  It thrives with a bit of shade and regular moisture.  This is an excellent choice for masonry walls and the trunks of mature trees.  It will clothe a wall with white flowers and turn a dull trunk into a floral masterpiece. 
   
Plant vines for fragrance in your garden.  Evergreen clematis bears showy white fragrant flowers clusters above shiny dark green leaves in spring.  Clematis montana is covered with vanilla scented pink flowers in spring also.   Carolina jessamine‘s fragrant yellow flowers appear in masses throughout  late winter into spring.       
Star jasmine is a wonderful vine for sun or shade and it’s intense fragrance near a patio or open window will delight you.  It is easy to grow and is generally not  troubled by pests. Pink jasmine blooms mostly in the spring but sporadically through fall with showy, sweet scented pale pink flowers.  It grows fast to 15 feet and is tolerant of drought.  It can also be allowed to cascade over a wall or from a hanging basket.
   
Other vines that are beautiful and easy to grow are the native honeysuckle, lonicera hispidula with its translucent red berries in the fall. Violet trumpet vine, white potato vine, passion flower, Lady Banks rose, hardenbergia, Chilean jasmine and wisteria.
   
The above vines are just a few of the wonderful vines that do well in our climate, in a wide range of soils and conditions.  They are pest resistant and need little fertilization or care other than pruning to control size if needed.   Look around your garden for a spot that would be enhance by a beautiful vine.

Quail Hollow & the Gene Pool

Few things can compare to walking on a scenic woodland trail lined with wildflowers.  Now that it’s officially spring I recently took a hike in Quail Hollow Ranch County Park to see what I could find. One of the unique aspects of this park is the number of rare plant and animals that make this valley their home. It didn’t take long to find the threatened Silver-leafed manzanita although it wasn’t blooming yet. The sandhill ecosystem where it grows among ponderosa pine is found in Santa Cruz county and no where else in the world.

Once upon a time, this land was under water, part of an ancient ocean, which uplifted to form the Santa Cruz Mountains about three million years ago. According to the Santa Cruz Department of Parks, the silt, sand and mud that had been deposited in that shallow sea later turned into the shale, sandstone and mudstone that make up Quail Hollow today. The diversity of this special place is mirrored in the patchwork of 15 habitats that are located in this small, secluded valley. Mixed evergreen forest, redwoods, grasslands, and a pond with surrounding riparian ecosystem mix with hot, dry chaparral and sandhill environments. The sandy soils here have eroded from the Santa Margarita sandstone and serve as an aquifer for the San Lorenzo Valley.

Hiking the trails among the blooming mimulus ,large-leafed lupine, Western Hound’s Tongue, manzanita and ceanothus made me think about the impact of our own gardens on the populations of native plants like those here.
Are we contaminating the native gene pool if we plant a mimulus, for instance, from southern California or a hybrid in our own garden?

The genes of all native plants have been sorted out over a very, very long time scale and they’re finely tuned to their environment. When you introduce an exotic gene – exotic meaning not of this place- it could be from a neighboring county, we don’t know the long term effect they’re going to have. If you live next to a wild population of a certain plant, like ceanothus, you should try to plant locally collected and propagated plants and seed. They are harder to find but local growers do collect seed and identify the source. On the other hand, ceanothus is a fire-dependent species and does not regenerate from seed except in the presence of fire or some other disturbance. If in doubt you could substitute a drought tolerant Mediterranean shrub that wouldn’t interbreed with local native plants.

It is probably not a problem for the home owner who lives in a neighborhood and wants to plant a couple of those cool, new sticky monkey flower hybrids in his own garden. If they do interbreed with the native population, in time whatever genetic pollution there is will probably die out. The home gardener is not planting fields of one type of plant that will interfere with the wild population.

There are many philosophies about planting California natives. There is no one-size-fits-all when it comes to this subject.  One thing for sure, we all want to preserve our wild areas like Quail Hollow.
 

Garden Tips for March

Spring is in the air. It’s always exciting to see the plants in the garden come to life. I’ve been invited to tour a  garden in Scotts Valley in April when many of the early flowering plants will be in bloom.  I’ve been to this garden before and there’s always an interesting tree, shrub or flower to enjoy.

One of my long term goals is to view the great gardens in the Santa Cruz Mountains. If you have a garden that you think others would like to hear about and you are willing to share it with me, please contact me. I’d love to spend time with you in your garden.

There’s so much to do now in the garden. If you are feeling overwhelmed here are some suggestions for the more important to-do’s.

* Check drip systems for leaks or clogged emitters. Flush sediment from filters and check screens for algae. You may need to add emitters if plants have grown significantly.

* Finish pruning and clean-up of trees, shrubs, vines and perennials. This includes fireblight die-back on pears, apples, hawthorn, pyracantha, photinia, crabapple quince and toyon., Prune out and discard diseased branches making the cut at least 6-8" below blighted tissue. Clean the pruning blades with alcohol or a 1:5 solution of household bleach to prevent spread of the disease. Also finish pruning and cutting back perennials and ornamental grasses. Go ahead and give grasses a 3-5" crewcut so fresh growth can emerge. Cut back old foliage of maiden hair ferns to allow new growth to take center stage. If you have Western sword ferns or another type that has winter or thrip damage, remove shabby looking fronds. Even if you have to cut back the entire fern it’s OK. It will regrow in just of couple of months.  Prune any other frost damaged plants when you see new growth begin.

* 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 compost and or mulch on top of the soil and let it slowly decompose and filter down into the earth.

* As you plant new additions to the garden add organic matter to the soil. If your garden’s soil is sandy, organic matter enriches it and allows it to hold water more efficiently. If your soil tends toward clay, organic matter will loosen it up and improve drainage. In well-amended soil, plants grow deep roots, are hardier and more resistant to disease. Organic matter, such as compost, planting mix and well-rotted manure, boosts nutrition and improves soil structure.

* Fertilize if you haven’t already done so. Citrus, shrubs and fruit trees just emerging from dormancy are begging for their first meal of the season. Lawns begin their spring growth now also and benefit from a boost of nitrogen. You can also spread a thin layer of composted manure over you lawn. Leaving you grass clippings on the lawn will benefit it by shading 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 or manure and a light application of balanced fertilizer. They respond to phosphorus especially in the spring for root growth, stem sturdiness and flower development. Wait until azaleas, camellias and rhododendron have finished blooming before feeding them.

* The most important to-do for March 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.

Allergy-Free Gardening

Mea culpa. It was brought to my attention by a reader who suffers from pollen allergies that blooming . Acacias are largely pollinated by insects and have heavy pollen that doesn’t tend to become airborne.  It’s the non-showy, quiet ones you have to watch out for. Warm temperatures earlier in the year are already creating havoc for those who have to deal with seasonal allergies.

About 25-30 popular landscape plants are responsible for the majority of plant-related allergies in California.   During the height of the pollen season- from late February to June- there are often thousands of pollen grains in every cubic meter of air.  One can breathe hundreds of them with every breath.  Though pollens can travel many miles, the majority tend to stay in the general area of their origin.

Redwoods, oaks, alders, ashes and other wind pollinated trees like olives, birch, box elder, cypress, elm, juniper, maple, fruitless mulberry, pine, walnut, willow and privet are the major source of spring pollen. Most  native plants are good in the sneezeless landscape but if you have bad allergies or asthma it best to avoid wind-pollinated ceanothus, elderberry and coffeeberry. 

You may not be able to avoid these culprits growing on other’s property but you can get the most out of your own backyard by creating a sneezeless landscape.  Replacing existing plants may be impractical but planning future plantings with these things in mind will save you a lot of headaches down the road and let you enjoy the sunshine outside in your garden.

Flower type is a good way to judge plants.  The best looking flowers usually cause allergy sufferers the fewest problems.  Plants with bright, showy flowers are usually pollinated by insects, rather than by the wind.    These flowers produce less pollen and  their pollen is larger and  heavier and sticks to the insect rather than becoming airborne and lead to sneezing, a runny nose and watery eyes. 

Some trees that are good for anti-allergy gardens are apple, cherry, dogwood, magnolia, pear and plum. Shrubs like azaleas, boxwood, lilac, Rose-of-Sharon, hydrangea and viburnum are also not likely to cause problems. Good flower choices include  alyssum, begonia, clematis, columbine, bulbs like crocus, daffodil, hyacinth.  Also dahlia, daisy, geranium, hosta, impatiens, iris, lily, pansy, petunias, phlox, roses, salvia, snapdragon, sunflower , verbena and zinnia.  Lawns of perennial rye grass, blue grass and tall fescue blends are usually OK as they will not flower unless allowed to grow to 12" or higher.  Bermuda grass, on the other hand, can pollinate when the lawn is very short, sometimes as quickly as a few days after mowing.

Hopefully, this cooling trend will not cause problems for allergy sufferers. Symptoms may become worse if the body reacts to the disappearance of the pollen following its initial appearance only to have to have more of it later in the spring. According to Dr. Stanley Fineman, an allergist with the Atlanta Allergy and Asthma Clinic, "You become sensitized to it, so when you’re…re-exposed, you can get an even more violent allergic reaction."

Here’s to a sneezeless spring for you allergy sufferers.