Growing Temperate Palms on a "Gulf Stream" Coast
In our temperate European climate cold is less
of a problem than wind and damp. Here's how to cope.
Roger Dixon, Torquay, Devon, UK
Chamaerops No.34 Spring 1999
Torquay's famous Jubaea Chilensis attracts palm
enthusiasts from around the world.
Torquay lies on the south coast of Devon in SouthWest
England. This is one of the "Gulf Stream" coasts of the
British Isles. Here, the sea temperature rarely drops much below
10C/50F although, of course, the air temperature can drop considerably
below this.
With rocky coastal cliffs and wooded hills, dotted
with villas, falling steeply away to a small fishing harbour (now
a yachting marina!) the area has a similarity to the Riviera coasts
of the Mediterranean. As such, Torquay has become known as the "English
Riviera".
Sunbathers, who are interested in the hottest summer
temperatures, scoff at this description. For, whereas the Riviera
coasts of the Mediterranean have weeks, if not months, during which
the temperature rises into the nineties, the temperature in Torquay
rarely exceeds 22C/75F.
However, exotic plant growers, such as many readers
of "Chamaerops", who are more interested in winter minimum
temperatures, might find the Riviera description more appropriate.
In Torquay, the average daily minimum temperature
during January and February is 3C, the average daily maximum temperature
is 10C. The average lowest annual temperature is about -3C. The
extreme minimum temperature (i.e. the lowest recorded over a 50
year period) is about -8C. These figures are only one or two degrees
lower than the equivalent temperatures for Nice on the French Riviera.
Hence woody, perennial plants that can get through the winter in
Nice unscathed have a fighting chance of surviving the winter in
Torquay.
The Torquay parks department have taken advantage
of the local climate to plant many palms including Trachycarpus
fortunei, Chamaerops humilis, Phoenix canariensis, Butia capitata
and Washingtonia filifera In a local private garden there are two
one hundred year-old Jubaea chilensis.
Are there no problems with growing temperate palms
in Torquay? There certainly are! These can be summarised in two
words: "damp" and "wind".
Torquay gets about forty inches of rain a year, most
of which seems to fall as a thick, penetrating drizzle. Stand in
front of a lawn sprinkler and you get the general idea! Given the
water retentive nature of the local soils it is imperative to provide
good drainage if the palms are not to suffer root rot during the
dormant period. Good drainage means adding plenty of gravel to the
soil, and preferably planting on a slope (readily available in Torquay!)
or in a raised bed.
The damp climate also causes problems with providing
insulation. Straw or dried leaves used as insulation becomes a soggy
mess, not only losing any insulating properties but also providing
a breeding ground for fungus spores which can lead to palm rot.
In my (very limited) experience it is better to concentrate
on those palms that will get through the typical winter without
protection, only providing insulation for the short periods when
damaging cold threatens and removing the insulation as soon as the
cold snap is over. This ensures a good flow of air around the palm
decreasing the risk of rot.
The other problem is wind. It is difficult for those
living in inland areas to realise how damaging salt laden winds
can be to gardens, large leaf evergreens such as palms being particularly
vulnerable. Even in calm weather plants get a continual buffeting
from sea breezes. When storms race in off the Atlantic trees can
lose large branches and shrubs can be completely uprooted.
Even in a compact garden, such as mine, with no line
of sight to the sea, dense planting of bushes and trees as wind
breaks is necessary if palms are to grow well. After all, no one
wants an array of tatty palms in their garden whether the stunted
growth is due to frost or wind.
Certain palms have leaves that are more resistant
to wind damage than others. Of the fan leaf palms Chamaerops humilis
is definitely more resistant than Trachycarpus fortunei Amongst
the feather leaf palms Butia capitata seems more resistant than
Phoenix canariensis or Jubaea chilensis Cycas revoluta also seems
fairly wind resistant.
The other problem caused by wind is "wind rock".
This occurs when a palm is planted. The root hall is placed in the
hole but, because the wind continually rocks the palm, the palm
roots fail to penetrate the surrounding soil. Secure staking for
one or two years is needed to overcome the problem.
I would be very in-terested in hearing from other
palm growers from the "Gulf Stream" coasts of NorthWest
Europe, in particular in their experiences in combating these twin
problems of damp and wind.
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