[gardeners] Oxypetalum (Tweedia) caeruleum

Bob Kirk (gardeners@globalgarden.com)
Tue, 7 Jul 1998 22:19:57 -0500 (CDT)

   Just placing the occasional attempted post to Gardens-L on the record
for any prospective employer, but it's worth asking if any of the southern
gardener types here have ever grown this and had better luck with it.

>Date: Mon, 29 Jun 1998 21:54:35 -0500 (CDT)
>From: Bob Kirk <reikirk@ksu.edu>
>To: Gardens & Gardening <GARDENS@LSV.UKY.EDU>
>Subject: ID of blue plant at Longwood Gardens
>> Can anyone identify the plant at
>> http://www.delanet.com/~dgsmith/980621_1933a.jpg?  It was in a container
>> at Longwood Gardens.  It's truly blue -- not a bit purple.

   The ring of odd structures where you'd expect the stamens to be suggest
it's an Asclepiad (milkweed family), in which case it's no doubt Oxypetalum
caeruleum (or Tweedia caerulea).  Been 2-3 years since I saw one, but the
leaves & flower look about right - and as you note, it's one of those  
rarities that is genuinely *blue.

   Never did all that great in central Ks., but might have wanted a little
less competition - and sun after 1:00 as well. From either South Africa or
South America, so maybe it didn't like our heat?   (Canadian) Harrowsmith
Annuals is the only garden book I've ever seen it in, anyway.
   Good luck doing a web search, but a hit at NCSU I can't access says this
naturalizes in the lower Piedmont, so maybe heat isn't the problem. A bit of
research mentioned on another site notes it is day-neutral but long days do
cause internode elongation.... exactly my problem with it - too much plant
for the not very large or very numerous flowers.  Surely that stretchiness
would be exaggerated up in Canada (or maybe that's the only way they ever
get a usable plant out of it in a short season).

   What did this one look like? With diligent pruning to turn it into
something bushy & less straggling (and hopefully with more than a half
dozen flowers at a time) I'd imagine it could be a fairly showy specimen.