My primary windbreaks are a long but rather sparse
beech hedge, some conifers and hollies, and a number of large sprawling
rhododendrons. Within these confines I have set out to create my
own 'subtropical' garden.
I use hardy evergreens such as yuccas, fatsia, eucalyptus,
arbutus, yew and holly, while relying quite heavily on bamboo to
create the basic subtropical structure. Amongst these, I grow fairly
hardy exotics, such as phormiums, palms and cordylines, some of
which need protection in the severest weather. I overwinter tender
exotics, such as agaves, hedychiums, cannas, callistemons, puyas,
coloured cordyline and some palms in a conservatory and greenhouse
and bring these into the garden for the summer months.
While bamboos survive the severest of winter weather
unprotected it is advisable to provide a thick mulch of well-rotted
compost or manure, annually, preferably in the autumn, as this reduces
frost penetration to the roots, promotes healthy growth by way of
extra nutrients and helps to retain moisture.
Snowfall can be frequent and heavy during an average
Sheffield winter and this can do considerable damage to some evergreens,
although its insulating qualities are a bonus point. In fact it
is rare for us to have a sustained cold spell without the advantage
of an insulating layer of snow. Despite the frequency of snow, I
have experienced no significant snow damage to bamboos. Moderate
to large species such as Phyllostachys, Sasa, Pseudosasa, Thamnocalamus
and Fargesia are frequently flattened by snowfall. Under these circumstances
it is best to leave well alone, as under these conditions the bamboos
are well insulated against subsequent frosts. When the snow melts
the culms spring back up again as though nothing untoward had happened.