A (Second) Close-up View of the

Common Hyacinth

Hyacinthus orientalis

by Brian Johnston   (Canada)

In an earlier Micscape article, I studied two varieties of this plant with white and blue colourations.  When the opportunity arose to photograph a bright reddish-pink example, I simply couldn’t resist!  I’m certain that the thought of having this spectacularly coloured, and intensely scented plant to brighten my environment during the intensely cold and snowy late February period, played a large part in my decision.  (It is fortunate that hyacinths can be ‘fooled’ into believing that it is spring in February.  In my area, ‘real’ spring may not appear until late April or early May!)

The genus Hyacinthus used to be a member of the lily family Liliaceae, however it is now considered the ‘type’ genus of its own family, Hyacinthaceae.  The plant studied here is often referred to as the ‘Dutch’ or ‘Common’ hyacinth.  It is characterised by each bulb producing a single, densely packed spike of flowers.  Wild hyacinth is native to Turkey and the Middle East, and it is said that both the Greeks and the Romans grew the plant.  During the 16th century, it reappeared in the historical record when the German doctor Leonhardt Rauwolf brought plants collected in Turkey and Iran to Western Europe.

Just how tightly packed the flowers are on a spike can be seen in the first image in the article. The three images that follow show the bell-shape of the flowers, and the relatively short stalk that connects each flower to the sturdy, tapered, cylindrical stem.  The images also show each plant’s attractive, bright green, narrow leaves.  Each leaf has a convex outer cross-section, and a concave inner cross-section.  Notice also that the buds of immature spikes reveal very little of the flowers’ bright colouration.

Very early buds, like those seen in the image that follows, are often pale greenish-yellow in colour.

As time passes, the buds darken to a lime green colour, with almost imperceptible hints of pink.

Several days later, the buds begun to show definite signs of their final colour.

At this stage the buds are peanut-shaped, and have strange, white, bow-tie shaped structures at their bases.  Bud stalks are extremely short.

Closer views of the bud tips reveal the sculptural quality of the tightly packed sepals and petals. Also note the close packing of the buds making up the spike.

The next stage in the blooming process has individual buds moving away from one another, beginning at the base of the spike, and moving upward.  Bud colour intensity continues to increase, again from bottom to top.

If you carefully examine the images that follow, you can see that the outer sepals that surround and protect the three inner petals have begun to separate at the bud’s tip.

In the final stage, the three outer sepals and three inner petals open out to their final positions in which they are almost perpendicular to the flower’s base.  From the front, each flower resembles a tiny starfish.

In the 18th century, the common hyacinth was so popular that in Holland, the main commercial producer, approximately 2000 variations were said to be available.  It is not difficult to see why this plant was, and is, so popular.  Both its colouration and scent are spectacular!

Note in the four images that follow that each flower does have a stalk, although it is a very short one.  Also notice that at the base of each stalk there is a very small, colourless, triangular leaflet.  The first two images show the grooved nature of the plant’s main stem.

Because a flower’s sepals and petals are indistinguishable from one another, they should more properly be referred to as tepals.  Notice that most have random, complex, three-dimensional surface patterns.

Closer views of these patterns follow.

The plant’s main stem is much lighter in colour than its leaves.  Although within the flower-head the stem is deeply grooved, beneath it the grooves are very shallow and only noticeable by close inspection.

Much closer views of the lower stem reveal these shallow grooves, and the stem's surface texture.

Near the base of the plant, the overlapping sword-shaped leaves are a much lighter green colour.  The image on the right shows detail at the point where the leaves leave the top of the bulb.

Up close, the many parallel, longitudinal ridges that run the length of each leaf are clearly visible.  Note the speckled appearance of the leaf’s outer surface which becomes apparent at this viewing distance.

The time has come to take a closer look at hyacinth flowers.  Each has three outer pink sepals, and three inner pink petals which spread out from the tubular base of the flower.  Both sepals and petals are deeply coloured for most of their length, but become almost white near the top of the corolla’s tube.  Looking into the centre of a flower, one can just make out the yellow tips of its pollen producing anthers.

In order to get a better view of the flower’s reproductive structures I gently pulled the sepals and petals away from the corolla tube.  The images that follow show the group of anthers, each having a dark, almost black colour, and a coating of yellow pollen grains.  The reason that the female structures cannot be seen is that they are positioned at the bottom of the corolla tube, beneath the anthers and their supporting filaments.

If one side of a flower is removed, the relative positions of stamens and pistils become clear.  Each white stigma is joined to a yellowish-green spherical ovary by a short, stubby, deep pink style.  The stigmas are at the level of the bottoms of the flower’s anthers.

Much closer views reveal the pollen grains on the surfaces of anthers, and the microscopic hair-like projections on the surface of each stigma.

If all but one of the pistils are removed, the grooved surface of the ovary is apparent.

Viewed under the microscope, the ‘seeds to be’ are visible within the ovary.  A higher magnification view of the ovary’s outer surface shows the ellipsoidal shape of hyacinth pollen grains.  The ends of the ellipsoids are sharply pointed in the grains.

Additional photomicrographs of various regions of a hyacinth petal show more pollen grains.

Two high magnification macro-photographs show the active surface of an anther.  Both images also show the upper section of the ovary with the pink, grooved style growing from its top.

If an anther is examined with the aid of a microscope, its liberal coating of pollen grains becomes visible.

The groove which bisects each pollen grain longitudinally is apparent in the scattering of grains on a microscope slide.

Photomicrographs showing the cellular structure of the dark edges of an anther can be seen below.  Although these areas appear almost black in the macro-photographs, the brilliant light of dark-ground illumination reveals that they have a brownish-red colouration.

Eventually, a flower’s sepals and petals disintegrate, and fall from the flower.  What remains in the example shown below is the ovary, and the remnants of the pistil.

The name hyacinth is believed to come from an ancient Greek legend.  Two gods loved a young Greek named Hyakinthos.  One god – (the god of the west wind) – observed the other – (the sun god) – teaching Hyakinthos how to throw the discus.  He was overcome with jealousy and blew the discus back.  Unfortunately it hit Hyakinthos on the head and killed him.  From his blood, the flower we now know as the hyacinth grew.  (The Greeks certainly had a vivid imagination!)

Photographic Equipment

The low magnification, (to 1:1), macro-photographs were taken using a 13 megapixel Canon 5D full frame DSLR, using a Canon EF 180 mm 1:3.5 L Macro lens.

A 10 megapixel Canon 40D DSLR, equipped with a specialized high magnification (1x to 5x) Canon macro lens, the MP-E 65 mm 1:2.8, was used to take the remainder of the images.

The photomicrographs were taken using a Leitz SM-Pol microscope (using a dark ground condenser), and the Coolpix 4500.

A Flower Garden of Macroscopic Delights

A complete graphical index of all of my flower articles can be found here.

The Colourful World of Chemical Crystals

A complete graphical index of all of my crystal articles can be found here.

 All comments to the author Brian Johnston are welcomed.

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Published in the October 2013 edition of Micscape.
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