Arum
John Grimshaw (Fri, 06 Apr 2007 12:07:34 PDT)

I have no doubt that Arum concinnatum is distinct from A. italicum, and it
certainly has no connection with the forms variously known as 'Marmoratum',
'Pictum' (or however you want to write them) and a growing list of cultivars
selected from the general gene pool. This is a very good example of the
benefits of the horticultural group system whereby similar plants can be
covered by a Group name, and exceptional cultivars distinguished by a
cultivar name. I would suspect that in this case Marmoratum Group would be
the preferred name for A. italicum (subsp. italicum) with strongly
white-veined leaves. The name 'Pictum' has confusion potential with the
autumn-flowering Arum pictum and is best avoided. Many A. italicum do not
have these extensive white veins, and are either totally unmarked or with
smaller patches of white or grey on the upper surface of the leaves.

I think that Peter Boyce is correct to regard A. italicum as a single very
variable species, but he has not yet addressed the issue of those plants
with 'italicum' characters but 'maculatum' markings. My view is that most of
these so-called hybrids are in fact versions of A. italicum, but study is
needed.

Although often recomended for the winter garden, which their foliage
certainly adorns, the various A. italicum cultivars and forms are at their
best about now as the foliage builds to its maximum before the
inflorescences appear. My favourite is 'Nancy Lindsay', which isn't one of
the better-marked clones, but the leaves emerge at this time of year a
beautiful soft yellow. As they are rather big this gives a very striking
effect in the garden.

Of A. concinnatum forms the nicest I've seen and grown is 'Mt Ida', a
selection from Crete, with speckles of grey and black on very dark green
leaves.

John Grimshaw

Dr John M. Grimshaw
Sycamore Cottage
Colesbourne
Nr Cheltenham
Gloucestershire GL53 9NP

Tel. 01242 870567

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