TOW Oxalis - responses to various postings

Robin Attrill robin@rpattrill.freeserve.co.uk
Wed, 12 Nov 2003 15:21:49 PST
All,

I have a few comments on various postings, summarised below.

regards

Robin

Uli wrote.......
                                                  There is a particularly
nice tall growing plant
> form Ecuador (which I traded with nothing but an accession No) with mauve
pink
> flowers with very dark centres in umbels high above the leaves, it may
even
> bloom year round when kept in the appropriate climate. It needed a few
years to
> develop to its full beauty, I suspect that some Oxalis do NOT like to be
> transplanted every year, most do not mind, though.
>
I presume this could be the plant listed as Oxalis Sp.-Rcb Eq-V-2 in the
Oxalis listing of the Cotswold Garden Flowers website at
http://www.cgf.net/list.html  Sadly they no longer appear to sell it.

> There is also Oxalis articulata which forms finger-like tuberous stems
above
> ground. it produces mounds of fresh green leaves almost invisible under
masses
> of pink flowers, a nice edging plant and never a weed. This one definetely
> flowers all year in suitable conditions and is widespread in mild European
> gardens and is perhaps hardier than expected.
>
O. articulata/crassipes can be weedy in the UK - it is particularly
problematic if it colonises mown grassland where mowing operations spread
fragments which can form new plants.  It is generally not a problem in a
garden context.


> The Wiki pages on Oxalis are very nice and I was able to identify some of
the
> plants I grow (but having doubts about O. incarnata, there is nothing red
about
> it as the name implies) O "incarnata"

Under certain conditions the stems are reddish

> Some of the nicest Oxalis are not weeds at all but are painfully slow to
> increase.

In my experience this is true of most plant genera!!!


Dave Victor wrote........


>They are all grown in my standard one litre pots,
>in a mixture of a soil based compost and sharp grit/sand, roughly two to
one.

I use the same mix but mostly smaller pots, mostly 9cm squares due to very
limited space. These are adequate for all but the largest species.



>The second was another O. species, which turned out to be O.
>gracilis.

O. gracilis, or something very similar, is sometimes sold in commerce as O.
karroica, a name which I have not found in the standard Oxalis literature or
IPNI. It is a lovely plant.


>The third came to me as O. massoniana and, indeed, looked rather like that
>species until it flowered.  However, at the point, the flowers that emerged
>were almost identical to O. versicolor: white, with a pale pink edge to a
>reverse petal edge, so it appears similar to a barber's pole.  Another very
>pretty species, which I have tentatively identified as O. heidelbergensis.

O tenuifolia is rather similar

>Incidentally, thinking about identification, many of  you will grow O. 'Ken
>Aslet', which has been identified under a variety of specific epithets in
>the past.  Last year, Mike Grant, the senior taxonomist at RHS Wisley
>re-keyed the plant and confirmed it as O. melanostica.

I've held this view for many years - the spelling is actually melanosticta

Mike Mace wrote.....

>There appear to be many other interesting species of Oxalis, but I've
>never seen them available.  For example, Barbara Jeppe's "Spring and Winter
>Flowering Bulbs of the Cape" has paintings of beauties like O. tenuifolia
>(long tufted stems with white flowers on top), O. helicoides (long spindly
>stems with red flowers), O. convexula (looks like another alpine cushion
>plant, with big salmon-red flowers), O. ciliaris (looks like an Oxalis palm
>tree, with big pink flowers on top), and O. orthopoda (looks like a tiny
>telephone pole covered in Oxalis leaves, with a white flower shooting out
of
>the top).  Where can we find these things?

Many are in cultivation  - they have just not been commercialised. O
convexula is listed by Telos. Ensuring they grow in the habit found in
nature, as illustrated in the Jeppe book, is often difficult, particularly
in northern climes. Supplementary artificial light may assist.





More information about the pbs mailing list