Articles > Canopy


1 May 2003

THE IMPORTANCE OF CANOPY

 

The purpose of this article is to provide a glimpse of a half-hour workshop “The Importance of Canopy” to be given at Friendship Park, 1805 W. 9th Street, San Pedro on May 17, 2003.  Your Los Angeles Area Chairperson, Leland Lai, has planned several nice events for that day, like a self-guided walk through Averill Park (you’ll see the value of canopy in this park’s palm garden).  Next will be a tour of Joe and Linda Bird's palm garden, with clear examples of canopy.  You will witness firsthand how canopy can allow tender, tropical palms to thrive in an otherwise hostile environment.  Even sun-loving palms, and yes, even cactus, develop a deeper, darker, healthier color, which is more pleasing to our eyes than the lighter, parched look.

 

 What is the Function of Canopy?

1.      Prevents sunburn and subsequent drying out of leaves, which cannot be later reversed.  During low-humidity days, especially “Santa Anna’s”, there are less water droplets that safely diffuse the burning rays of the sun.  Actually a small fraction, i.e., 30% shade, is enough to prevent sunburn.  Try this experiment yourself.  On a hot, dry day around 2 o’clock walk in the sun with your face tilted toward the sun; note the uncomfortable feeling of your facial skin.  Now, walk inside a 50% shadehouse during this same period; note the ‘rosy’ feeling that your face has and the feeling you could stay in there for many, many hours. 

2.      Increases humidity.  Less water is lost thus the root system can easily manage the water needs of the plant.

3.      Moderates temperature.  The temperature is generally reduced in the summer months, yet heat-loving plants have sufficient warmth to do well.  This shelter also minimizes frost during the winter months.

4.      Provides a windbreak, especially during our southern California cold, dry winter months.  Many of the palms we cherish are from the southern hemisphere having a natural habitat that is warm and dry in the summer and cool and wet during the winter.  We can accommodate those palms by shielding them from the cold, dry air which could rapidly strip the leaves of their moisture.

 

During a PSSC meeting in May 1998, Dr. Mardy Darian gave a presentation of the use of palms from Madagascar in Southern California.  He began his talk with a very dramatic opening statement, saying the most important thing one should know about the Dypsis and Ravenea palms was “Canopy, Canopy, Canopy”.  You know, something like an exuberant real estate broker might do when attempting to sway you to purchase a particular home by saying, “Location, Location, Location”.  Well, honestly, I was certain that soil, water, fertilizer or something else was more important.  But years have passed and I’ve made some awful mistakes with respect to planting palms directly in the sun, yet I've been extremely fortunate with palms that have been allowed to “grow into the sun, all on their own”.  So now I’m completely in Darian’s camp concerning canopy—our California soil, if it can reasonably drain, is likely to be good enough.  Fertilizer might be nice but rarely vital.  The mass of soil for a palm will hold water a long, long time so that plant’s roots will remain moist.  Yes, proper canopy can mean the difference between a plant that languishes and a plant that is vibrant.

 

How do I create or take advantage of Canopy?

First, start with your location and follow Bob Burtscher’s good advice:  Know the track of the sun over your property for every hour of the day.  Really, this is not difficult.  You may find that you have a Cyprus tree that you can plant that fussy Ravenea mooreii within the shadow cast at 1-5 p.m.  It will be perfect there.

 

Note that the east side of your home gets warm, soft sunlight for about 3 morning hours.  After that the sun breaks over your roof and your roof acts as canopy for the remainder of the day.  So, a good candidate for this location is the Livistona chinensis which loves heat but prefers less-than-searing sun.

 

The north side of your home may have a roof overhang that will provide perfect shade, the year around, for that tender Chamaedorea stolonifera, Dicksonia fern or Cycas apoa.  When that fern tries to grow outside the shadow cast by the overhang, that portion exposed to the sun will singe.

 

Second, cover those sunstruck palms (marked ‘Shade’ or ‘Filtered’ in your ‘Palms for Southern California’ pamphlet) with 50% shadecloth.  It need not be fancy—a small patch above the crown held up with stakes or strung into position by connecting to the roof, a pole, etc. 

 

Third, start growing trees or palms that are fast-growing that will provide canopy, yet offer some balance to your landscape theme.  In 1995, I acquired a Howea belmoreana from Denis O’Malley and planted it out in the sun but covered it with 30% shadecloth (this means that 70% of the sun passes through the cloth to the palm).  This palm is now 8 feet tall and absolutely gorgeous.  But this is a palm that should not be planted out in the hot Escondido sun.  I have planted 6 different Archontophoenix nearby, very fast growing yet tropical-looking palms.  Very close is an imposing Floss Silk tree providing very nice, dappled light canopy, and I plan to place a few Schizlobium’s, the tall, mimosa-like tropical tree with a small head.  Eventually, when all of these trees have filled in, I will remove the shadecloth.  Darian suggests the evergreen Quercus agrifolia, the California Live Oak for canopy.  The late Kate Sessions of Balboa Park fame introduced, among many, the deciduous Tipuana tipu, the Rosewood tree—this is a fast growing tree that provides perfect canopy and will allow you to plant many filtered-light palms in the near future.  If you live within 10 miles of the coast you can grow successfully the evergreen (deciduous with frost) Spathodea campanulata, the majestic African Tulip tree.  Other candidates might be the nearly evergreen Cassia leptophylla, the Gold Medallion tree and the (briefly) deciduous Brachychiton acerifolius, the Australian Flame tree.  Of course, in the hotter interiors, an evergreen is preferable but certain deciduous trees may lose their leaves for such a short period that no harm will come to the palm planted below.

 

The Army/Navy surplus stores sell jungle netting, available in desert brown and plant green colors.  It may be a little ugly, or it may remind you of Viet Nam, but it provides a reasonably priced dappled light solution.

 

Hedges, fences, concrete walls can become part of your canopy scheme.

 

Don Hodel suggests that a greenhouse-grown palm (described as ‘Sun’ or ‘Gradual Sun’ in the palm pamphlet) may be planted out, directly in the sun, by placing a 3’ x 3’ patch of 50% shadecloth, supported by 3 wooden stakes, over the palm.  Make a small hole in the center of the shadecloth and place an unopened spike of the palm through this hole.  This spike will open in the sun above the shadecloth and be perfectly acclimated.  The leaves below the shadecloth are destined to turn brown and die within a year, and that is when the shadecloth can be removed.  What is important is that the palm is not shocked by a sudden kill-off of many leaves.  This procedure works great and should be used by those uninterested in the “inching-out into the sun” method of acclimating palms.

 

The very best method is to take advantage of low lying items, like rocks, bushes or small trees to provide initial shade and shelter to a newly planted palm.  As the palm grows, it grows up and out of the shelter provided, at a very slow rate and it “grows into the sun”.  This is exactly how most palms in habitat grow—they start at the base of the parent tree, very much sheltered from too much light or wind.  As they grow up, they push past the parent into the sun at their grown rate.  An example, I planted my Wodyetia bifurcata beneath a Queen palm on the south side of our home.  At first it was below the roof line and got no direct sun.  But time has passed, and it is breaking above the roof line and growing into the sun.  This palm is one of the nicest looking palms I have because it grows at its own rate and gradually experiences a minute difference of increasing sunlight each day.  Eventually it will be in full sun, and loving it!

 

 

References and recommended reading:

1.      ‘Exceptional Trees of Los Angeles’, Donald R. Hodel, California Arboretum Foundation, 1988.

2.      ‘Trees and Gardens of Balboa Park’, Kathy Puplava, Paul Sirois, Tecolote Publications, 2001.

3.      ‘Acclimation of Plants From Shade Or Greenhouse Environment’, Phil Bergman, found at www.junglemusic.net.

4.      ‘Chamaedorea Palms’, Donald R. Hodel, Allen Press, 1992.

5.      ‘The Diamond <> Lane Guide to Growing Palms in a Temperate Climate’, Don Tollefson, Los Angeles Screenwriter’s Guild, 1996.

6.      ‘The Palm Journal’, an illustrated bi-monthly publication of the Palm Society of Southern California, devoted to information about palms contributed by members living in California.  For membership, go to www.palms.org/socal or telephone    (562) 663-8842.  Refer to journal No. 167, November 2002 by Bonnie & Geoff Stein for a summary of topics of the past decade.

7.      ‘Palms for Southern California’, B. Osborne, T. Reynoso, G. Stein, 3rd edition, 2000.  A quick reference guide to assist the palm grower in understanding the requirements of palms that can grow in Southern California.

 

Even a Bismarkia Loves Canopy

 

During our last meeting at Friendship Park in San Pedro, a workshop concerning Canopy was held.  We learned the functions of canopy and we may have gone home believing canopy is necessary only for shade-loving/tender palms or only for an initial acclimation period of several months.  I’m finding that even sun-loving palms truly appreciate a gradual transition from full canopy to roaring hot sun.  In my case, I believe the specimens have become specimens because the time period has been over several years, not months.  Even a Bismarkia loves canopy.

 

I noticed that my friend, Karel Havlicek, in Dana Point with essentially filtered sun, could grow a Bismarkia flawlessly, reaching 12 feet or so, having a perfect appearance.  No curled edges, no dried strips, and no scars.  On the other hand, I have one that I planted as a large 15 gallon size, nearly bursting the pot, with about a 3 month acclimation period followed by fierce sun.  It is suffering indeed.

 

How about Ralph Velez’ or Dennis Willoughby’s Bismarkia?  Well, it appears that from these beautiful examples they can thrive in a filtered environment.  In my case, about 18 miles inland, I can shelter my palm for a while but eventually it must face the music.

 

My other Bismarkia, shown here in the photo, has a special place between 2 large granite boulders.  It is partly protected (dappled light) by an overhead Queen palm for the hot period from 1 to 4 p.m.  The rocks provide warmth (reflected light and stored heat), plus some shelter now while this palm is still small. Eventually it will grow above the rocks and catch 10 a.m. to 1 p.m. sun.  The important part is that this palm is being allowed to “grow into the sun”, at it’s own very patient rate. This palm has interesting shades of purple and is nearly perfect.

 

    

Bismarkia Nobilis 2003

 

David Minks