Lilium

Oriental Hybrid Lilium: The flowers gracefully unfurl...

The other day, my husband brought me a bunch of beautiful lilies (Oriental Hybrids) from Costco.   I could not stop telling him how much I liked them.  From a distance the flowers are pleasing to look at with the delicate shape of the six organized petals that gracefully open into a dramatic spectacle.  On closer scrutiny the flowers are not only elegant but amazing - a perfect explanation of a great design!

I have never owned an Oriental Hybrid plant or any of the Lilium species before so I have not had the chance to observe the plant personally.  Based on my research, I gathered that the Oriental Hybrid group is only one of the nine classifications of cultivated Liliums.  Genetically, these are hybrids derived from the following species:  L. auratum and L. speciosum[1] , and L nobilissimum, L. rubellum, L alexandrae, and L japonicum [2] along with several Japan native species.  The flowers are characteristically large and fragrant.  It contrasts with the rest of the traditional species with flowers that faces downward, these hybrids have flowers that are outward-facing as if looking up to the sky.  Lilium 'Stargazer', a common example of the Oriental Hybrid, got its name from this sky-pointing characteristic of its flowers.

'Stargazer' apparently originated in Humboldt County California through the genius of Leslie Woodruff, an independent plant breeder.  What is interesting is that for such a phenomenal flower, the exact parentage of this hybrid is not known because Woodruff did not document his breeding work in detail.  Obviously he was more concerned about the outcome than the process.  Fortunately this plant can be cloned easily - thus its characteristics are maintained and preserved.

The flowers looks angular when they are unopened.

Pin cushion-like stigma

Apparently there were two varieties (identities unknown to me) included in the bouquet I got... A pleasant provision!  The darker pink flowers boast broad stamens that are covered in golden pollen grains.  The filament that supports the stamen is light green in color.  At the center of the flower is the prominent pistil with a cushion-like stigma that resembles the appearance of a small head of cauliflower. 

Pollens seem loosely attached to the stamens.

The three-lobed stigma looks like a mini-cauliflower head

The other flowers are lighter in color.

The other variety is lighter in color with darker speckles that seem like "outgrowths" on the petals.  The filaments are greenish white in the center of the flower that gradually darkens towards the stamens.  The stamens are covered in chocolate-colored pollens.   The stigma is the same as in the other variety except that the color is purplish

Chocolate powder-like pollens cover the stamens.

Pistil: Purple pigmentation and sticky substance on the surface of the stigma. 

The filaments are white in the center and gradually darkening towards the stamen.

These stamens are beautiful...but today I had to ask one of my daughters to emasculate the flowers.  (Emasculation is the removal of the male reproductive parts of the flower, a procedure that is common in plant breeding.) The pollens contain natural dyes that can stain fabric - so this emasculation was done to protect the table cloth underneath the flower vase.  This is a recommended process for flowers that are used indoors - but since the sharp color of the pollens add so much to the beauty of the flowers; one can delay this process until the pollens begin to show signs of separation from the stamen.

 “And why do you worry about clothes? See how the flowers of the field grow. They do not labor or spin.  ~ Matthew 6:28

Schlumbergera

Schlumbergera truncata in bloom.

History. The Schlumbergera is a rainforest-cactus that originated from Brazil.  In Brazil, it is called Flor de Maio because it blooms from April to July, May being the peak of its beauty.  In fact it is a popular Mother's Day flower.   It was named, later on, after Frédéric Schlumberger (1823-1893), a Frenchman, who was a collector of cacti and other succulents (1).  The name "Thanksgiving or Christmas Cactus" was only part of a marketing strategy.  On this part of the globe (northern hemisphere), this plant happens to bloom during this time of the year.  Flowering period coincides with Thanksgiving and Christmas seasons depending on variety. 

Origin.  To be specific, Schlumbergera is known to have come from the tropical rainforest north of Rio de Janeiro. They are epiphytes which mean that they grow on the canopies of trees. Perched up above and on rocks under the shade of taller vegetation, they are adapted to dry conditions and attenuated light.

Photoperiodism.   As I have mentioned many times in previous posts, flower initiation in most plants is triggered by daylength or photoperiod.   Schlumbergera is a photoperiod-sensitive plant.   In my garden, it is regarded as an outdoor plant.  It has been my observation that flower initiation begins sometime in October when daylength is between 9 and 10 hours, therefore they are considered short-day plants (flowering when exposed to daylengths that are shorted than 12 hours).   

Schlumbergera can be manipulated to flower earlier or later by changing the length of light and dark period in a day (24-hour).  Short days can be simulated by subjecting the plants in a prolonged darkness (about 15 hours per day) for a period of one month.  Flowering can also be delayed by reversing the treatment - extend the days by providing few hours of artificial light before sunrise or after sunset.   When the flower buds begin to show, the plants can be brought out to normal conditions.    Artificially inducing the plants to flower is being practiced by commercial growers in order to coincide blooming with the best selling period.  

Flower buds appear on the far end of the stems.

Leaflessness.  These cacti do not have leaves.  Instead they have phylloclades.  Phylloclades are modified branches characterized by being flat and the ability to photosynthesize.  Although they are not leaves they perform the role of leaves for the plant.  Unlike true leaves, phylloclades do not fall (abscise) off with age; instead they turn woody and brownish because a new generation of phylloclades grow from the older ones (just like a lateral branch grow from a more mature branch).  In the absence of leaves, plants do not wilt.  Prolonged exposure to water stress result in shriveling of the plant which is preceded by observed lightening of the green coloration.   Flowers are borne on the apical end of the phylloclades.  

 Soft serration on the phylloclades: characteristic of the Thanksgiving cactus. 

 The perianth at an early stage (sepals, petals, and the tube).

The perianth at opening. 

Reflexed petals.

Observations on the Flowers.  The petals reflex (bend backwards at an acute angle) further exposing the stamens and the anthers.   One peculiar thing that I noticed is that the petals right above the reproductive parts did not reflex upwards.  This tendency of the plant could be nature's way to keep the pollens dry - an adaptation mechanism that is necessary for rainforest plants such as the Schlumbergera species.

Picture taken behind the petals to emphasize the perianth tube.

The stigma prior to opening has an ovoid shape...

 androecium (male parts) and gynoecium (female part)

The stigma extends past the length of the stamens - opening into a claw-like shape.   This is an important feature considering that the flower droops down at opening.  In this position the pollens conveniently falls into the sticky stigma - allowing successful pollination.

The stamens are fused to the perianth tube.

When I opened one of the flowers it came to my attention that the stamens are fused to the perianth tube.  In the more common flowers (take the rose for example), the petals are not attached to either the androecium not the gynoecium.    

Inside the perianth tube.

The flowers are very shimmery. 

Schlumbergera, an epiphyte that has a precise sense of timing... 

She models her bold and shimmery flowers when her rivals are still asleep.

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(1)  http://en.wikipedia.org/wiki/Schlumbergera

Understanding the Epiphytic Orchid

Orchids I saw at the gardens of the  Intercontinental Hotel (Makati).

The Mediterranean climate here in California allows us to grow a wide variety of exotic plants.  However, with my recent trip to the Philippines, envy crept all over me and my humanity gave in when I saw the way orchids are growing there.  I can grow them here but it would not be as easy as when they are grown in their native habitat.   Here we enjoy the dryness of the Mediterranean air and despise the humidity of the tropical breeze.  However, we know that the epiphytic-orchids feel the other way around.
 

The Greenbelt Shopping Center boasts beautiful orchids that are planted between buildings.

Epiphytes.  Epiphytic plants (roots are above ground) like most orchids derive nutrients and water from the atmospheric air.   Orchids growing on tree trunks are a common sight in wooded areas of the Philippines as well as in home gardens and as well as in public gardens.  Gardeners bring these beautiful plants near their homes and they tie them to a tree and voila!  Unlike their terrestrial counter parts that have a prolonged access to soil moisture, epiphytes live in a more or less arid (zerophytic) conditions.  The roots, being in the air, are dry most of the time.  Water from the rain settles down way below the reach of the roots.  Sunshine not only provides the needed light and warmth to the leaves but it also lifts up the water up in the form of vapor.   Here in California, the air is so dry that it sucks even the moisture from my skin.   Before the orchid has a chance to drink a little, the moisture vanishes in mid air.

 

                       

Orchids growing on trees near my sister's house in Cagayan.

Adaptation mechanism.  Orchids generally require 60-80 percent relative humidity for optimum flowering.  This high humidity requirement is not always achievable but orchids have adapted to the fluctuating available moisture.  Leaves come in different shapes (flat, folded, or even pencil-like leaves) and all these help the orchids adapt to their environment.  Most orchids have thick fleshy leaves, similar to that of the succulents that allow them to store water and resist drying out.

                       

More orchids at Greenbelt, Makati. 

The gardens provide a pleasant place to take a break from stressful Christmas shopping.

Orchids have specialized roots called velamen.  These are the white shimmery roots (as seen in the above picture).  These are the roots that are used to both anchor the plants and absorb water and nutrients from the air.  What is special about the velamen is that they are made of multi-layered thick cell walls.   The property of the velamen prevents cellular collapse during periods of dryness and acts as a barrier to water loss.  When the tips of the velamen are green it means that the orchid is happy. 

Orchids at my old High School (ANRVHS) in Abulug.

In the Philippines, just like any other marine tropical place, orchids grow voluntarily on trees.  The home-grown orchids likewise, perform naturally well.  On the contrary, growing epiphytic orchids here is like having a plant in ICU all the time.  

Many times I have tried growing epiphytic orchids here in my garden; so far I have not had much success.  Is it just me or is it the climate? 

I'm Back from the Philippines

Typical rain in the Philippines.

Some of you might have noticed my recent lack of "blogtivity".  The reason is simple - with my family, I traveled to the Philippines.  Originally I planned to take a laptop with me however in a desire to travel lightly; my husband thought that an iPhone was sufficient.   I found out later on that writing on a touch screen is ineffective for gardener's fingers like mine.  Then I though that I could also post pictures knowing that they can speak louder than words...but sometimes life is not all that simple.   Two of the three small cameras we brought stopped working when we got to Cagayan, the northern-most province of the Philippines.  It was raining so hard that moisture must have penetrated the casing of the cameras.   The only one that remained functional was the one that was stored it in a ziploc bag.   

The Philippines has a Tropical Marine climate as influenced by the sea.  It is always hot with always high atmospheric humidity.  There are only two climates namely wet and dry seasons.  Although it is expected to rain every month, some months (June to November) are extremely rainy due to the monsoon winds.   The rest of the months (December - May) are characterized by lower precipitation due to the dry trade winds.  

Did you know?

1.  The English word "boondocks," comes from the Tagalog word "bundok", meaning "mountain.

2.  The Philippines is composed of 7,107 islands.  Some of them cannot be seen during high tide. :)

3.  The Philippines was a colony of Spain for 300+ years (1521-1898). 

4.  The Filipinos were first introduced to the English language by the British invaders in 1762.

5.   Today English language is taught in schools starting from third grade.  It is the official medium of instruction in high school and college.

6.  The Philippines has the same land area as Arizona.

7.  The Philippines has a population of 91 million.

White sand in Santa Ana, Cagayan.

 Just to give you a glimpse of the place where I was during the last two weeks...

and greetings to you all!

Mystery of the Cyclamen Flower

Most plants that have experienced the summer find rest in autumn as they follow a common earth-tone color.  Red, yellow, orange and brown are normal.  Then there are those radical plants that seem to rebel against this trend.  One unexpected colors of fall comes from the cyclamen flowers.  Not only do they provide a fresh shift from the "dying or resting theme" of those plants that have gone through the rigors of summer, they also provide a renewed crisp life of the season.  Since there are very few varieties of flowers in bloom, I had the luxury of observing this plant more closely than usual. 

Pendant-like blossoms.

The cyclamen flower starts in a droopy position with the end tip of the petals pointing downwards.  The petals are folded in a very organized manner and twisted tightly together forming a beautiful pendant that gracefully hangs on the long pedicel.

The petals turn upward, one at a time.  Flowers exhibiting this tendency are called "reflexed flowers". This phenomenon in directional growth of plant parts can be explained by a differential growth on the opposing surfaces any plant part.  In the case of the cyclamen flowers, growths on the opposite surfaces of the petal are not the same.  The inner surface undergoes a faster cell division or elongation than the other side. 

One petal turns upward at a time.

Reflexed Flower

Flowers are designed in such a way that they contribute to the success of reproduction.  The reflexed petals may seem to make pollination easier than in other plant species since the style is clearly sticking out as seen in the above picture.  One would wonder why seeds rarely form from cyclamen flowers without human intervention.  So I did a little bit of research and found a suitable explanation.  There is an evidence that the stigma is inside instead of the outside the style (Reinchardt S., Ewald F., Hellwig F.).  In normal flowers, the stigma is the sticky part of the flowers where pollen grains would stick to prior to its growth in the style during pollination.  In cyclamen, it is reversed - the style was shown to have a terminal aperture which closes at some point during anthesis thus limiting pollination time. The chemical that controls this opening and closing of the style is not determined at the present.

There's always something new to learn from the garden and cyclamen is indeed an interesting flower!

What's happening in your garden today?

Halloween Tomatoes

Old and sagging.

Pecked with developing pus.

Shrivelled with crusty scab.

Bruised, wounded, and fungus-infected.

Wrinkled and leathery.

My tomato plants need to find their resting place. 

Duck and Duckweed

This park was one of our favorite places to go when the kids were little.  There was a fountain in the middle and the water was really clear we could see small fishes in the water.  The other day I was surprised to see that it is now almost completely covered with tiny little floating plants called duckweeds (Lemna minor).   

Given the right conditions, duckweeds can be very prolific.  One reason for this fast growth in this pond could be high nitrogen content of the water.   The sloped surrounding grass area is kept green year round - meaning high amounts of nitrogen is applied on a regular basis.  It is expected that some nitrogen find their way to the pond through runoff.  A second reason for the high nitrogen content of the water could be due to the animal waste from all the ducks in area.

It appears that the duck population in the area cannot keep up with the growth of the duckweed.  I wonder what the Community Service District will do with this pond - to get rid of the duckweed infestation.  They could keep it that way or do something to remove it so that the water can be clear again.  They could increase the duck population but that will only increase the amount of animal waste going into the water.  They could skim the duckweed regularly but that would be labor intensive.  Duckweed is rich in nitrogen and would make an excellent composting material; local gardeners can be encouraged to do their part and harvest some of the duckweeds. 

Any suggestion?

HortiCOOLture - Spiderweb-like Hair

The Sempervivum arachnoideum is very unique succulent in that it has the appearance of an organized entanglement. If you are not familiar with this plant you might get the impression that they are infested with spiders.  On the contrary, those webby structures on the leaves could be a defense mechanism against insects. 

Trichomes loosely connect leaves together.

The white webs on the leaves are specialized trichomes that connect the leaves together.  As seen from the picture above, there are normal trichomes (hairs) on the surface of the leaves but those that form the webs are coming mainly from the pointy tip and margins of the leaves.  These spiderweb-like trichomes stretch as the leaves grow.  That is why they are increasingly longer and sparse on the periphery of the rosette.  The growth of the trichomes starts with the growth of the leaves as indicated by the concentration of very tight webs in the middle. 

Trichomes are "leaf hairs".    They come in different forms and in some cases there are different types of trichomes in one leaf as exemplified by the Sempervivum arachnoideum.  (Just like in humans and animals - the hair that grows on the head is different from those that grow on the arms, so is in plants.) They have different functions depending on the nature or habitat of the plants.  Trichomes can serve as a deterrent to insects.  Also they can serve as defensive layer against extreme environmental conditions such as wind, heat, cold, ultraviolet rays.  In some cases trichomes also serve as a mechanism for salt tolerance. 

Webby trichomes make the plants look frosty.

Sempervivum arachnoideum is a type of succulent that originated from the Alps (1) and I believe that their trichomes play an important role in its ability to adapt in the snowy, windy and cold conditions of the Alpine Mountains.  It is an evergreen plant and can tolerate freezing temperatures.  Although they do well in dry conditions, adequate water helps the tiny plants to grow at a faster rate. 

Pink flowers float from the multitudes of Sempervivum aracnoideum rosettes.

Sempervivum arachnoideum is a plant to give to an arachnophobe. :)

Happy Halloween!

1) Elijah Walton, Thomas George Bonney (1869).  Flowers from the Upper Alps: With Glimpses of Their Homes

Cymbidium Updates

As of this week, spikes are coming out from the Cymbidium California 'Sun Acres'.  Compared to last year's bloom, these flowers are coming out early.  Considering that we just got into fall season not that long ago, this is indeed a pleasant surprise.  Last year I learned that flower initiation in cymbidiums is greatly affected by the differential temperatures (maximum and minimum) of the day.   They require between 10-20 degrees (F) difference between the day and night time temperatures before flower initiation depending on variety.  Out of the five different cymbidiums I repotted last spring, only this variety is flowering so far.  However, all of them are looking very healthy which indicates that they are all set to put on their own show and just waiting for the opportune moment. 

I intended to pursue cymbidium as my new hobby plant for this year.  My plan was to buy at least 100 plantlets for a start.  My husband, who is always very supportive, already purchased all the pots that I would use for this purpose.  These pots, which are still in a huge box, haunt me every time I see them in the garage. And yet, here I am still vacillating as to whether it is a good idea or not. 

Gardening is a time-sensitive endeavor.  A delay in implementation moves the reward further away.

Parthenocarpy

Parthenocarpic Orange

Par.theno.carpy
Origin: Greek word parthénos = maiden; karpos = fruit)
Literal meaning: virgin fruit
Botanical meaning: enlargement of the ovary into a fruit without fertilization. 
(Parallel meaning: pregnancy without a developing-baby in the womb.)

Parthenocarpy is the phenomenon behind most seedless fruits.  Parthenocarpy is fruiting without the union of a male and a female egg cell.  The lack of fertilization means that there are no seeds in the fruit.  If there are seeds, they are not viable and are not capable of germinating.

Many times we take seedless fruits for granted and even despise the ones with seeds.  Although it is a natural occurrence in some varieties of some plant species (such as banana, persimmon, pineapple, and orange) parthenocarpy is an "abnormal" condition.   I say this because technically fruits are supposed to have seeds.  Seed is the reason for the fruit.  

Seedless grapes with traces of undeveloped seeds.

Fruit development begins with pollination. The moment the right pollen grain touches the stigma (the sticky surface of the pistil), fireworks of events happen as if a switch button has just been set to ON.  First a pollen tube develops as a passage way for the sperm nuclei in the pollen to the reach the ovules (part of the flower that develops into a seed). As soon as the pollen reaches its destination fertilization occurs and a zygote (fertilized egg = seed) is developed. Then several hormonal changes happen to signal a succession of events that support a continued development of the zygote. Gibberellin level suddenly rises resulting in the enlargement of the tissue surrounding the ovary. This tissue eventually differentiates to form the fruit.  Fruits tissues come in different charactreristics:  fleshy (as in grapes, peaches and apples), hard (as in nuts) or dry (as in dandelions and grains).  In short, fruit development occurs when a seed starts to develop. 

How does parthenocarpy happen? 

1.  Uncompleted Seed (Aborted Embryo).  Pollination triggers fruit development but in some cases the embryo is aborted before successfully developing into a seed.   The landing of pollen on the stigma is enough to trigger fruit formation that continues regardless of failed seed development.  Seedlessness through parthenocarpy does not involve fertilization.  However, seedlessness can still happen even after fertilization has already occurred through stenospermocarpy.  In this mechanism, the embryo is aborted just the same but at a much later time (1). The 'Thompson' and 'Flame' seedless grapes are examples of stenospermocarpy; traces of undeveloped seeds are visible when the berries are opened (see picture above).

2.  Genetic Disorder (Chromosome Imbalance).  Plant species which are triploids cannot successfully produce seeds - they are genetically sterile. The banana we buy from the grocery store is parthenocarpic because it is a sterile triploid (two sets of chromosomes from one parent and one set from the other) instead of the normal diploid where you get one set of chromosomes from each parent.  Pollination happens but fertilization does not.  The tiny black dots inside the banana are traces of the unfertilized ovules.  In the case of seedless watermelon, triploidy is induced through genetic manipulation. 

3.  Absence of a Perfect Mate (Self-Incompatibility).  Some plants species are self-incompatible - they are self sterile when pollinated by the same variety of plant.  In order to fruit, these species require pollens from a plant of different genetic makeup.  Navel oranges, pineapples, and clementines are examples of self -incompatible plants.  For example, when an orchard of the same variety of oranges is grown, fruits would come out seedless (parthenocarpic).    

4.  Manipulation by Steroids (Application of Growth-Regulators).  There are several growth hormones that play a role in parthenocarpy but for the current topic, our focus will be gibberellin.  Gibberellin is a phytohormone (plant produced-hormone) that is also produced by certain fungus called Gibberella fujikuroi.  Through this fungus, gibberellin-like compounds known as gibberellic acid (GA) can be produced apart from the plant.  GA is known to promote cell division and enlargement; when applied to plant at a strategic time and rate, the plant will respond accordingly.  This knowledge regarding the response of plants to applied GA and the knowledge that endogenous (produced within) gibberellin levels in plants increase upon fertilization and thus triggering fruit development have changed the horticulture industry.  Flowers can now be fooled into thinking that fertilization has taken place and thereby developing fruit-tissues.  In other words, fruits can be induced with the application of gibberellic acid.

Parthenocarpy is a delightful abnormality because the seedless fruit maintains the appearance and taste of its normal counterpart.  This is the reason why growers have capitalized on it to improve the commercial value of some crops.  Research work continues to exploit the application of parthenocarpy on more plant species where the seed is not for consumption.  

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1) Table Grape Berry Growth and Development: A Review