Walking Irises: A case of mistaken identity - Neomarica and Trimezia
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| Neomarica caerulea “Regina” |
Ok we have had these plants for
ages so in many ways it is an old friend. When I was a little boy we had them
growing in the garden at Centipede Alley at Moto’otua. When we moved to Alafua
they were dug up and transplanted there. I latter dug some up and transplanted
them at Moto’otua and then to Vailele where they disappeared while I was away.
I assumed they died out due to the place being on the coast but according to
various sources they are drought and salt tolerant so maybe it was something
else. In any case it was not till around
2008 that I stumbled across a couple plants being sold under the Banyan trees on
Beach Road in Apia and made arrangements to buy one after work.
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| Neomarica caerulea “Regina” |
I planted that single plant at
Malifa and as it grew and sent up offsets. I waited patiently until they were
sufficiently big, then dug the whole clump up and divided it and replanted the
individual plants. When I moved to Alafua I took some with me and planted them
there again as the ones that had been left behind had disappeared.
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| Neomarica caerulea “Regina” |
We always referred to this plant
as a Blue Iris although later on I began to doubt the accuracy of this
name. At Malifa there were some plants that looked like they were closely
related to this since they resembled each other except for a number of
differences.
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| Yellow Walking Iris flower |
First of all the flowers were much
smaller and yellow speckled with brown. Also they had many more flowers on long
thin flower stalks. Indeed the whole presentation of the flowers was entirely
different as you can see.
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| Blue and Yellow Walking irises (not to scale) |
On top of that they had this
bizarre tendency to grow little plantlets out of the flowers. These would grow
and the weight of the growing plantlets would make the stalk bow down until it
touched the ground and the plantlets took root. They also multiplied by sending
up offshoots.
The Blue ones on the other hand at
most had three flowers per stalk and sometimes these flowers developed seed
pods although I have never successfully grew any seeds out of them ... yet.
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| Neomarica
caerulea "Regina" |
The other difference compared to
the Yellow flowered plant is that the Blue one had much larger and sturdier
leaves and a slightly different centre rib structure. Other than these
differences the flowers apart from size and colour were remarkably similar
which to me indicated that they were related being at least of the same genus.
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| Leaf of Neomarica
caerulea "Regina" showing centre rib |
The close resemblance of the
flowers and the tendency of the yellow one to grow plantlets led me to the Neomaricas otherwise known as “Apostle
Plants” or “Walking Irises”.
The name “Walking Iris“ refers to
the tendency of the plant to grow plantlets and “walk” across a lawn while the
“Apostle Plant” reference alludes to the belief that they always have twelve flowers per stalk which I can confirm is NOT
true.
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| Yellow Walking iris Flower and plantlets forming on flower stalk |
The whole “Walking” thing is what
still confused me because the Blue ones that I have and the Blue ones that I
have seen on line do NOT “walk” at all. Interestingly one site (LINK)
addresses this very issue noting that:
“Although it is considered a walking iris, we
have only seen it walk under extreme stress.”
That statement is extremely
interesting and could perhaps point to a reason for the tendency for these
plants to “walk” because when you think about it developing plantlets that will
“walk” could be a way of the plant to try to ensure that it continues by
growing in a location that is hopefully more favourable to the continuation of
itself than if it just sent up another offset. The “walking” plantlet would end
up taking root some distance away from the mother plant which in some cases
might make a world of difference to its survival. But that is just my theory.
But getting back to identifying
the Blue flowered plants, the closest that I have found that matches the Blue
Irises I have is Neomarica
caerulea “Regina”.
There are a number of other varieties which I assume are
cultivars of Neomarica caerulea. However,
Neomarica caerulea “Regina” is the one
that I think is the one that we have had all these years.
The Yellow one I have tentatively identified as Neomarica longifolia which some identify
as being synonymous with Trimezia
martinicensis and given the common name of Yellow Walking iris.
Trimezia is a genus which belongs to the same family as Neomarica – which is Iridaceae.
PHOTO of Blue Iris
As it is I picked up another variety from Tului Peters at Samoan Nursery up at Aleisa a few months ago. It is a smaller plant
than even the yellow one and if I remember correctly it has white flowers. But
has not yet flowered and seems to be growing very slowly. Actually the plant is
rather small, being about 12 inches / 30cm in height. I am assuming that this
is its full size because one of the two plants I obtained had a plantlet which
you would only get from a plant that had flowered unless this is yet another
variety that manages to “Walk” without having flowered first which I find very unlikely since from what I have read,
flowering is part of the process.
PHOTO of small Neomarica
Maybe it is a Neomarica northiana given how it is supposed to be white.
I guess we will have to wait and see what it flowers look like.
As for the identity
of the Yellow Iris that are still uncertain. I did some research on the whole Neomarica longifolia versus Trimezia martinicensis issue and found
some interesting information.
First of all due to the close resemblance between plants of Noemarica and
Trimezia
they are often confused and misplaced in the wrong genus or treated as
synonymous.
However, according to information from the Kew Royal
Botanical Gardens citing Chukr & Giulietti (2001), there are
distinctive vegetative characteristics that distinguish the genrea which are
more accurate than looking at the flowers alone.
These are summarised as follows:
With regards to the Underground system Trimezia
ALWAYS has a corm while Neomarica has a rhizome in 90% of the species
and a corm in only 10%.
For the leaf bases (cataphylls) Trimezia
has it’s cataphylls arranged in a spiral while Neomarica
has it’s cataphylls arranged in a plane with the base of one clasping the one
above
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| Leaf base of neomarcia caerulea |
For the leaves Trimezia has
flattened or circular leaves while Neomarica has leaves that are sword-shaped
folded lengthwise
For the flowering stems (scape) Trimezia
has circular in cross section and never leaf like while Neomarica
has a flattened and leaf like flowering stem.
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| Flowering stem of Yellow Walking iris |
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| Flowering stem of Blue Walking iris |
Taking this information into account I think that the yellow
irises that I have are actually a Trimezia. I indicate the genus only because I
discovered that there are two species of Trimazia that match the description of
the ones I have; T. martinicensis and T. steyermarkii
So now I need to figure out if it is Trimezia
martinicensis or Trimezia
steyermarkii.
... to be continued
Taxonomy
- Family: Iridaceae – Genus Neomarica –
Species: Neomarica caerulea
- Family: Iridaceae – Genus Neomarica –
Species: Neomarica longifolia
- Family: Iridaceae – Genus Neomarica –
Species: Neomarica northiana
- Family: Iridaceae – Genus Trimezeia –
Species: Trimezia martinicensis
- Family:
Iridaceae – Genus Trimezeia – Species: Trimezia steyermarkii,
Medical use
No information found
Glossary: PLEASE NOTE I will be updating the post to include the glossary as soon as I have completed it
Cataphylls:
Corm:
Rhizome:
Scape:
Offsets:
References PLEASE NOTE I will be adding all the references and links to the on line source as soon as possible
Agristarts Entry on Iris Neomarica
caerulea “Regina” LINK
Fairchild Tropical Botanical Garden Entry on Neomarica caerulea LINK
Kew Botanical Gardens LINK
Wikipedia Entry on: Iridaceae
Wikipedia Entry on: Neomarica
Wikipedia Entry on: Trimezia
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