Dusty Miller

Dusty Miller (Jacobaea maritima) is a unique plant with silvery and lacy leaves which varies with variety.  which made it useful in creating contrast and accent against the predominantly green or red foliage in the garden.  It's neutral color makes it a great choice for as a filler plant in any border.

Last season, I planted dusty miller along with marigolds and blue lobelia and alyssum in the large containers that hold orange and pomegranate trees.  The arrangement was delightful all the way to the late fall.  But now only the silvery dusty miller remains.   Dusty miller, as much as it is labelled as an annual in your local nursery, is a perennial.  Yes, dusty miller is a perennial plant.

When the plant gets to a mature stage, the shape becomes irregular and the stems get woody.  The plant seem to undergo bolting at flowering.  However,  this can be solved by pruning the plant to shape.  As for the ones I have in my containers (as seen in the picture below) they will soon be transferred to the ground before I plant new annuals into the containers again.  

Banksia integrifolia

Botanical Name:  Banksia integrifolia

Common Name:  Coastal Banksia

Family:  Proteaceae

Country of Origin:  Possibly Eastern Australia

Named after Sir Joseph Banks

This picture was taken at the UC Davis Arboretum.   The flowers were very striking and hard to miss. I noticed at least two specimens of Banksia during our recent visit there but I am not sure what varieties they are.  

Tanacetum parthenium

Tanacetum parthenium (L.)

Common name:  Feverfew; Wild Chamomile

Other Names: Chrysanthemum parthenium

                        Leucanthemum parthenium

                 Pyrethrum parthenium 

                 Matricaria parthenium

Family: Asteraceae

Origin:  The Balkan Peninsula

Tanacetum pathenium (feverfew) is a perennial plant that is traditionally cultivated for its medicinal properties. Extensive studies throughout the ages have shown that the flowers and fruits are known to contain parthenolide which accounts for the medicinal potency of this plant.  However, beyond its therapeutic uses, tanacetum parthenium is also an important ornamental plant in landscapes.  Dainty white flowers with yellow center rise above the canopy of the plant in the summer and fall - making it an excellent plant choice for mixed borders.  

In my garden, feverfew came as a volunteer plant - in other words, it is a self-seeding plant.  Over the years it has spread and I had to deliberately contain it on the eastern side of the patio providing an added visual interest in that area. This plant requires very little to thrive. In our Zone 9 area, it is almost evergreen but I cut it back every year in the winter to give it a clean fresh growth for the spring.  

Suggested Reading:  Feverfew (Tanacetum parthenium L.): A systematic review

Dahlias in my Garden

Fig. 1   'Arabian Night' in the rain.

One of the year's new plants in my garden is dahlia. Dahlia is a tuberous tender perennial known to have originated from Mexico. Nowadays, there are many hybrids that have resulted from breeding and selection all over the world. As a member of the Asteraceae family, dahlia is related to daisy, chrysanthemum and the sunflower. Dahlias come in different colors and sizes. As a beginner, I selected four different varieties that featured large flowers but slightly inferior in size to the dinner-plate varieties.  

Fig. 2   Dahlia 'Arabian Night' has yellow stamens

1.  Dahlia 'Arabian Night'.  Introduced in 1951 (Weijers), this  variety has the looks of a classic dahlia with its gorgeous black red flowers with contrasting yellow stamens (Fig.  1 & 2) in the center.  Being a semi-dinner plate, the flowers are large but not so large - four inches in diameter. Great for cutting, the flowers remain intact when they fade.  Of all the dahlias I planted this year, this was the first variety that showed the first blooms.  

Fig. 3   Dahlia 'Stranger':  Spring Blooms

Fig. 4   Dahlia 'Stranger': Summer Blooms

2.  Dahlia 'Stranger'. It is a vigorous grower with dark green leaves.  This was the earliest variety to emerge from the ground.  The flowers are creamy in the middle radially shifting to pink with white margins on the petals.  The height of the plants was between 3-4 feet.  The flowers last for a week and then the petals begins to fall.  Unlike the 'Arabian Night', the flowers drop its petals as it fades. This variety started blooming in May.  It was also noted that the earlier flowers (opening when temperatures were averaging in the high 70s) were more yellow (Fig. 3) than those that opened during the hotter summer period (Fig. 4.).  

Dahlia 'Pom-pom Mix'

3.  Dahlia 'Pom-pom Mix'.  Apparently there were two varieties in this mix.  One was a  bright magenta with yellow stamens and not a lot of petals - relatively speaking.  The other one looks like a sunny side up - the center of the flower resembles an egg yolk against the creamy outer layers of petals (Fig. 5).  It was my observation that the plants in this mix lacked the vigor that was displayed by the other varieties I planted.  The plants are generally shorter; their stems and branches are thin and are prone to lodging. 

 Dahlia 'Lady Darlene' - Front view

Dahlia 'Lady Darlene' - Back view

4.  Dahlia 'Lady Darlene'.  Huge mop-heads of petals in a gradient of red-to-yellow color are the flowers of 'Lady Darlene'.  From the front view, the flower looks predominantly cream - the petals being edged with red. It has massive flowers of enormous size!  The stalks are huge and sturdy and the leaves are dark green.  This was the last variety that bloomed.  I observed that the first flowers were more yellow than the succeeding ones where the gradient in color was less clear.Thus, supporting my theory that some flowers tend to exhibit less intense colors under high temperatures. Considering that this is a summer blooming variety, I must resign to the fact that the flowers will be mostly the washed-out version of  'Lady Darlene' in my Zone 9 garden.  However, I would presume that the Pacific coastal gardens will show the fiery red/yellow rendering of this lady.

This is the first time dahlias are grown in my garden and so far, I am very satisfied with the result and experience.  There were many lessons I learned about them which I will talk about in the future.

Dahlias are low maintenance plants but they require a lot of water to show their best.

Royal Poinciana Tree

Fig. 1   Royal Poinciana (picture taken at the Mauna Lani Bay)

Royal Poinciana (Delonix regia)

Family: Fabaceae

Adaptation: Tropical- sub-tropical regions

Common Names:  Flame Tree; Flamboyant Tree;

                          Peacock Flower; Gulmohar

One of the trees that caught my attention during my (and my daughter's) recent trip to Hawaii Island is the Royal Poinciana Tree.  It has a spreading habit which becomes more pronounced as the tree matures (Fig. 1).  In some cases the width of the canopy is greater than the height of the tree. Delicate fern-like leaves cover the arching canopy.  Once a year, the tree puts on a show of bright red-orange flowers that come in huge clusters.  At the peak of the blooming season the tree is covered with massive blossoms at which point the foliage becomes insignificant.

Fig. 2   Large pods hang beneath the canopy of Royal Poinciana

After the colorful show, some of the flowers develop into large pods - characteristic of the fabaceae family (Fig. 2) - which contain the seeds.  At this stage, the flamboyant inflorescence of the tree is taken-over by the interesting appearance of black pods that are supended under the canopy.

Fig. 3   'Royal Poinciana' in the tropics.

I have seen Royal Poinciana trees in the Philippines, Belize and even in the warmer coastal areas of California but I'm sure that I will never see it flourish in my own garden.  The winters here - although relatively mild - will not agree with the tropical requirements of this tree (Fig. 3).  However, I have read that its smaller cousin, the Dwarf Poinciana (Caesalpinia pulcherrima), can tolerate colder temperatures. Hence, I might still have hope. :)

Tradescantia somaliensis: Trichome-enhanced Beauty

Botanical Name:  Tradescantia somaliensis

Synonym:  Cyanotis somaliensis

Common Name:  Kitten Ears, Furry Kittens, Pussy Ears

Fig. 1  Newly replanted Tradescantia somaliensis from a 2-inch pot.

Tradescantia somaliensis  is an evergreen tender perennial with a notable tolerance dry conditions.  It is known to have originated from Somalia, as indicated  by its species name 'somaliensis' although it would not be a surprise to see find out that the plant is also native to other countries in the African continent with similar climatic conditions.

It is a curious plant with pointed (lance-shaped) leaves that are edged with striking trichomes which give the appearance of hairy kitten's ears. It's trailing growth habit and makes it an outstanding container plant (Fig. 2).  When grown outdoors, the plant needs protection from the direct afternoon sun particularly in the hot areas like ours (Zone 9).  For indoor cultivation, choose a bright location to ensure that the plant will remain compact.

The trichomes that line its leaf margins make Tradescantia somaliensis 

a very interesting interesting plant.

Fig. 2   Tradescantia somaliensis: Fast-growing yet compact.

Propagation of this plant can be done easily through cuttings and layering.  In my case, I usually take cuttings after blooming period.  That way I get to enjoy the flowers first.

Once a year, try a new plant in your garden and learn about it. 

Torenia: My New Shady Lady

Fig. 1    Torenia fournieri

Every year I try one or two new plants in my garden and this year one of them is Torenia (Torenia fournieri). Torenia, commonly called 'Wishbone flower' is a beautiful annual plant that performs best in the shade. The tubular flowers come in shades of pink, yellow, and blue on the lobes - depending on variety. The tube often comes in white with a blotch of yellow in the interior of the lower lobe (Fig. 1). The plant grows up to 12 inches tall and wide and blooms continuously in summer until temperatures drop to freezing point.

Fig. 2    Torenia blooms in summer to late fall.

Torenia is generally easy to care for.   For best results, plant it in the shade and where the soil is fertile.  Keep the soil moist especially in hotter weather condition.  Pinch young plants to induce branching for a more bushy appearance of the plant.  Fertilize regularly with complete fertilizer to promote profuse blooming. When growing torenia in containers, put container-plants together to create a shadier and cooler environment (Fig. 3).

There are no known serious insect and disease problems but they could be susceptible to powdery mildew and possibly root rot - depending on soil.

Torenia is giving me a positive first impression.  So far, it will continue to have a place in my garden as an annual plant (replacing impatiens) until I find a better one.

Fig. 3   Torenia enjoys the shade of taller plant.

Try new plants in your garden - just for fun!

Fortune Plant (Dracaena fragrans)

Dracaena fragrans 'Masagaena' in bloom.

Dracaena fragrans is one of the most important houseplants in the United States because of its ability to tolerate low-light environments and low maintenance.  In the Philippines, it is grown both as an indoor or outdoor plant.

This plant is known by so many names and for different reasons. With its broad and elongated leaves that resemble that of corn (Zea maize), Dracaena fragrans is nick-named corn plant or cornstalk plant in this part of the world.  On the other hand, its botanical name indicates a significant olfactory characteristic - "fragrans".  This plant's ability to exude sweet odor outweighs all other characteristics that it is used to universally describe the species of the plant.  With such names we could say that this type of dracaena is a fragrant corn-looking plant.  However, in some countries it is called 'Fortune Plant'. There is a superstition that revolves not just in the Philippines but in the rest of Asia.  If the plant blooms in your care, then good fortunes will abound in the home.  The blooming time seems to be unpredictable that people associate it with the elusive incidence of good luck. :)

Dracaena fragrans is sometimes called Corn Plant.

For me, it is not uncommon to see this plant bloom. My mother had one that bloomed outside her front door year after year.  Everyone who came to our house after dusk knew it was in bloom even if they didn't see the flowers.  Here in my house (in California), there are three potted Dracaena fragrans - one of them is about eight feet tall and the other two are about six feet tall - all of which I've had for years now.  I purchased these plants at different sizes.  It has been my observation that only the mature plants - with a minimum trunk diameter of one inch- showed flowers.  However, not all plants with the same size of trunk bloomed.  One of my plants did not bloom this year even if it has larger trunk than the other two that bloomed.  Therefore, I have to come up with another theory -- that the plant has to be exposed to not one but a combination of critical factors prior to flower initiation. I think the plant blooms when they reach a certain age and accumulated experience.  How to quantify such variables remain unknown to me.  I'm sure there are scientific literature out there that explain this mystery.  But before I find them, I will enjoy the secret belief that my Dracaena fragrans is signaling the arrival of good fortune into my house.  :).
.

Dracaena fragrans line a village road in Cagayan,  Philippines.

Traditions, superstitions and beliefs determine the way cultures look at plants.  

Growing 'Woolly Rose'

Fig. 1    Woolly Rose (Echeveria cristata 'Doris Taylor') flowers

Every summer in my garden, the Echeveria cristata 'Woolly Rose' (a.k.a. Echeveria 'Doris Taylor') sends out colorful flowers that look like candies.  The rosette foliage of this plant is covered evenly with a thick mat of trichomes that gives it a velvety appearance - thus the name Woolly Rose.   Not only the plant is beautiful but it is also a source of nectar for the hummingbirds (Fig. 2).  Whenever my plants bloom, I move the ones that are in pots to a place where we can enjoy the view from the kitchen window.  

Fig. 2    When in bloom, Echeveria cristata is a hummingbird magnet.

Tips in Growing Woolly Rose 

1.  Soil.  Plant Woolly Rose in the garden where the soil is well drained.  Improve drainage of clay soils by adding sand or pumice in planting area.  In containers, use cactus mix for good drainage and weight.  Adding good amount of Perlite and sand to regular potting soil works as well.  

2.  Sunlight.  Woolly Rose is adaptable to a wide range of environments but the plant will look its best in the right place.  In the summer (Zone 9), position Woolly Rose where it will get a few hours of morning sun or a short period of afternoon sun.  Too much exposure to sunlight will result in washed out yellowish color of the leaves while too little sunlight gives relatively greener foliage and longer internodes.  The right amount of sunlight will give the plant a bluish green color and compact rosette foliage.  Contrary to popular belief, succulents thrive best in partly shaded environment.

3.  Water.  The plant can tolerate periods of dry conditions but they grow faster and look better if they get adequate water.  Adjust watering based on the weather.  Watering is needed more frequently in summer and spring time, when the soil dries up faster, than in the cooler months of fall and winter.  The size of container is also a factor to consider when it comes to watering.  Plants in smaller containers require more frequent watering than those in larger containers/

Fig. 3    Echeveria cristata planted along with some Aloes.

 4.  Fertilizer.  Woolly Rose performs better when it gets sufficient soil nutrients.  Although the plant does not need a lot of fertilizer, it is responsive to fertilization during growing season.  A low dose of complete fertilizer is all the plant needs.  Succulent/cactus fertilizers (2-7-7 and 1-7-6), available at local nurseries, are easy to use and can be applied as often as every other week.  

5.  Protection from Frost.  Woolly Rose is easy to grow - the only problem, especially where I live, is the susceptibility of the plant to frost damage.  In areas where freezing temperatures are expected, protect the plant by moving them to a sheltered area.  With a little bit of protection this plant will continue to provide a delightful touch in the succulent garden.

6.  Propagation.  The plant is easy to propagate through cuttings.  Stem cuttings collected under the lowest leaves are the fastest to root.  Collect and stick the cuttings where there is a little bit of moisture and warmth. Figure 3 shows Woolly Rose growing from the sides of an orchid plant. Cuttings were directly planted into the holes.  Some succulents can be easily propagated from the leaves but this is not the case with Woolly Rose.  

Fig. 4   Trichome-covered rosette foliage.

Note:  Extreme temperatures, drought, and nutritional deficiency are conditions that can cause stress to Woolly Rose - all of which can contribute in the loss of the basal leaves and exposing a dark brown stem (Fig. 4).   However, this is not necessarily alarming.  In fact, this is a natural process that gives that plant an aged look. 

Dioscorea macrostachya

 Dioscorea macrostachya 

Synonym: Dioscorea mexicana

Family:  Dioscoreaceae

Common Name:Tortoise Plant

Country of Origin: Panama, El Salvador, Mexico

Fig. 1  Caudex on close-up view - resembles a tortoise shell.

The caudex which is the thickened and enlarged base of the stem is what gives this plant an extraordinary visual appeal.  Part of the caudex grows above-ground exposing a hardened outer layer that resembles a tortoise shell .  As the caudex expands, the hardened layer breaks into almost regular polygonal plates that becomes protuberant with age leaving deep furrow in between (Fig. 1).  

Fig. 2  Flowers and leaves on long vines

The pictures here are images of the specimen Dioscorea macrostachya at the Conservatory of  Flowers in San Francisco.  From the appearance of the stem and leaves, this perennial plant looks like and ordinary vine (Fig. 2).  Capable of growing up to 36 feet in a year, this plant is a vigorous grower.   Unless you take the time to  guide your eyes to follow where the vine originates, it would be so hard to imagine that the caudex below (Fig. 3) is related to the far-reaching vine with the heart-shaped leaves.  

The plant  

Fig. 3    Branches arising from the caudex.

As a normal sequence of events, every year, a new set of branches emerge from the apical end of the caudex and dies back at the end of the season depending on growing conditions.  In the tropical forest where this plant would be found in nature, the caudex would be sitting in the shade where it prefers to be with lots of water.   Sunlight requirement for this plant is relatively moderate.  The new vine would then have to reach up above the other plant canopies to access to direct sunlight.  Thus a rapid growth of the vine is necessary for existence.  The rate of growth of the caudex is a function of the photosynthetic rate on the foliage.  

Fig. 4      The Caudex: Tortoise-like

Dioscorea macrostachya is grown as an ornamental plant as it adds oddity to any plant collection.  

Suggested reading on Caudiciforms:
http://www.bihrmann.com/caudiciforms/subs/dio-mex-sub.asp

Find time to walk in a garden today.

Streptocarpus: My Own Plant

Streptocarpus spp.

Family: Gesneriaceae

Common Name:  Cape Primrose

Country of Origin: South Africa, Madagascar and  Asia

Fig.1    Streptocarpus flowers intermittently throughout the year.

It's been two and half years ago since I first saw a Streptocarpus in full bloom and the plant was not mine.  This time I have a clone of that same plant which has been growing in my kitchen.

Streptocarpus is probably one of the most beautiful flowering houseplants.  It is regarded in high esteem by plant enthusiasts not only because of its pleasing beauty but also because of its durability  as a plant. It is an evergreen, herbaceous  plant that grows well in shade - making it a great indoor plant.  This stemless plant blooms almost throughout the year as long as it is regularly fed with complete fertilizer (preferably with a high phosphorous content). They are related to the African violets but have a different morphological structure that makes them more appealing than their shorter relatives.

Fig. 2     Flower buds originating from the petiole of a leaf.

One of the most interesting observations on Streptocarpus is that flower buds originate from the basal section of the leaves (Fig. 2).  That's right; the flowers emerge from the leaves.   The first flower bud always grows closest to the axil as seen on the picture above.  The flowers come in clusters and indeterminately arranged on long slender peduncles that extend well above the top of the leaves giving the appearance of floating flowers (Fig. 3 and Fig. 1).  The flowers open in succession which allows a prolonged flower show (Fig. 1 and 5).

Fig.  3.  Clusters of unopened flowers.

Fig. 4  Delicate tubular flower on slender peduncle.

The flowers come with a delicate tubular corolla which extends out into deeply scalloped lips that resemble individual petals (Fig. 4).  The tube of the flower is usually clear white with increasing pigmentation towards the lobes with the lower lips being darker than the upper lips.  The peduncle (stem-like structure that supports the inflorescence) starts out curled and slowly uncurls as it elongates to display the ethereal inflorescence (Fig. 4).

Fig. 5     Flowers open in succession

Cultural Management  

1.  Provide sufficient moisture but not soggy soil.  Over watering is a common cause of damage on the plant.  Water only when the top of the soil feels dry.  

2.  Position plants in light but not direct sunlight.  East facing window sills work best.  Putting plants on a hot sunny window sill will cause burning on the leaves. 

3.  Feed regularly.  Fertilize during watering using low fertilizer concentration (about 25% of recommended rate).

4.  Allow sufficient room to grow.  Divide or re-pot only when the pot is full of roots to the next size using peat-based multi-purpose media.

5.  Deadhead regularly.  Remove spent flowers (including dead leaves) to encourage continued flowering and to avoid Botrytis (Gray Mold) infection.  

6.  Monitor the occurrence of pests.   Regularly inspect plants for white and greenflies, aphids, mildew, and mealy bugs. (These pests can be a problem but so far I have not seen them on my plants.)  It is easier to control pests at the early stage of infestation.

Streptocarpus: a sturdy and delightful flowering houseplant.