Re: Kew-eries
Tim wrote:
>I slipped in a quick visit to Kew on Sunday as part of a few days in
>London and, as usual, came away with a notebook full of scribbles
>about desirable plants.
Glad you got back safely Tim. My drive back here was uneventful apart
from discovering that the clutch on my was giving up the ghost!
>First a general question. Why are plants from Lord Howe Island only
>possible (and then only barely) in the most mild UK gardens? Is it
>purely a matter of winter temperatures? Or is it also a question of
>summer heat? And/or soil conditions??
I don't think Lord Howe's Island is that noted for exceptional heat in
summer, but its even climate - never very hot, never very cold does
pose problems. The variations we experience here are probably far too
wide for many of its native species and even down here, with winter
lows of no more than minus 2.8C lasting for barely 3 hours, can prove
overly taxing. Also, our winters are simply too cool and dark even on
'warm' days. In theory Howea belmooreana (Kentia palm) should succeed
here and I keep promising myself I'll give it a try one day, but I
suspect it will languish miserably. Theory also suggests that palms
such as the New Zealand (plus off-island) Nikaus - Rhopalostylis
sapida, cheesemanii etc.should really thrive, but in practice most
tend to dwindle away. Low winter daytime temperatures are probably
the culprit since 8 or 10C max for several weeks on end in December is
barely warm enough to keep them 'ticking over'. That said, I'm having
some considerable success with R. sapida which even in seedling stage
are proving to be very cool tolerant, but I've lost R. cheesemanii.
>Some examples from that island's flora which caught my eye:
>To Dietes robinsoniana (which does, occasionally, get grown over here:
>the writer Eden Phillpotts grew it in Torquay before World War I,
I didn't know it was grown anywhere in the UK nowadays - I wonder if
Kew could be persuaded to.... no silly idea!
>Tasmanians are normally better bets for us in the UK, certainly for
>gardeners on the west coast. Why, then, is the splendid Doryanthes
>palmeri so marginal? (Dave Poole will almost inevitably be growing it
>in Torquay of course! Ha!)
Doryanthes are not native to Taz. but I understand they are grown
there in a few favoured spots. Actually, I haven't got D. excelsa yet
although I'm promised both the normal species and the rare white
flowered form when my pal 'in the trade' comes over from Oz with
another pile of plants, later this year. Any seedlings I've had of
this have been extremely weak and have all died before getting past
the 3" pot stage. I suspect I need to start with a strong, well
established division. Erm... I do have a very handsome looking,
division of Xeronema callistemon though - and it looks very happy
surrounded with piles of rotting seaweed. I think I told you on
Saturday that the soil here is little more than broken up stone and as
such, needs irrigation even in winter. The Xeronema gets just that -
crushed rock and seaweed, no soil.
>Does it come from very low down and so from
>a virtually frost-free environments? Or is there some other necessity
>we're by and large failing to provide, apart from frost-free-ness?
Despite its provenance, I would suggest that Doryanthes might prove
moderately hardy in very sheltered spots, but .... and its a big but,
are our summers hot enough for it? Frost tolerance is only one small
aspect in terms of overall hardiness and many plants which can
tolerate far colder winter temperatures than we ever see in the UK,
fail abysmally because in general, our summers are neither long enough
nor hot and sunny enough. Most years we can just about get away with
it down here on the south coast - especially in warm, sheltered spots,
but the chances of success dwindle significantly the further north you
go. If a warm summer's day is in reality just barely out of the low
20's,(C) it is not hot enough for a lot of plants which normally
expect several months in the low to mid 30's.(C)
Of course there are probably thousands of exceptions to this and the
only real way to find out is to try. To my mind one success outweighs
20 failures and although disappointments can and do occur, I never let
these put me off. I suspect you are the same.
Dave Poole
Having just discovered that sitting outside my local pub drinking in
the fragrance of the huge Silver Wattle (Acacia dealbata) nearby, is
every bit as refreshing as drinking the 'old amber nectar' (thats beer
to everyone else). I got more than enough of both yesterday afternoon
so I was double refreshed!
