Re: Leucospermum in the PNW?

Nan,
In general the Leucospermum tribe, especially L. cordifolium and its cultivars are not hardy below 25F.  L. reflexum is probably amongst the hardiest of the commonly grown species, as Jeff Rosendale of Rosendale Nursery in Watsonville reports this has come back with new regrowth after temps below 25F, and says it may be good down to 20F  In any case, all Leucospermum need to be grown hard, and encouraged to have no new growth from late summer onwards if they are to have any chance of surviving sub-freezing temps.  In my experience with L. cordifolium cultivars, they regularly get freeze damage and may even die if they still have soft new growth under normal garden conditions here in Berkeley, at temps of only 28/29F.  Leucadendrons in general are much more cold hardy, and you will see a lot more survivors of hard freezes in the PNW or places like England with these, over Leucospermums.

I know that the collection at UC Santa Cruz and also at SF Botanical Garden suffered major losses of Leucospermum species and cultivars after the 1989/90 bad freeze with 10 days of below freezing temps, and again in 2007, although more came through at UC Santa Cruz because they do grow their collection hard, with minimal summer water, and not all died even at temps as low as 25F.  So far this winter, temps in the PNW have already been so severe, that no Leucospermums could be expected to survive there, except if they were container grown and brought inside to wait out the cold.  The genus just isn't hardy enough to handle their periodic freezes as a garden plant in the ground, except if treated as an expensive half hardy annual...


--- On Sun, 2/15/09, N Sterman <TalkingPoints@plantsoup.com> wrote:

> From: N Sterman <TalkingPoints@plantsoup.com>
> Subject: Leucospermum in the PNW?
> To: "medit ucdavis" <medit-plants@ucdavis.edu>
> Date: Sunday, February 15, 2009, 10:16 PM
> Anyone in the Pacific NW US who grows Leucspermums
> (pincushions)?
> 
> Nan
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