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.

HortiCOOLture - Armored Plant

Fig. 1   The bizarre porcupine tomato (Solanum pyracanthum).



Ornamentally Odd
When all the basic plants are in place in the garden, an oddity here and there is in order.  This week our local nursery is offering a plant that would fit the bill.  The "Porcupine tomato" botanically known as Solanum pyracanthum (Fig. 1) is a plant that is armored with spikes all over. 

In spite of being prickly, some ornamental features can be attributed to this plant.  The bright orange spikes provide a pleasing textural and color contrast against the bluish green velvety leaves (Fig. 2).  The royal purple petals are complemented by protruding yellow stamens in the middle.   Eventually, small cherry-tomato-like fruits will take the place of the colorful flowers. A plant with such attributes definitely makes a statement in any garden.

Fig. 2   Dagger-like spikes on land under leaves of Solanum pyracanthum

Physical and Chemical Threat
This may be an ornamental shrub but the plant is definitely for your eyes only. The velvety green leaves may look soft and friendly but the dagger-like spikes (Fig. 2) that are spread all over the plant  make the plant look utterly foreboding.   I would not recommend this plant near playground areas.  The quills would deter any one from touching the plant but the danger does not end there.  The plant is known to contain various toxic substances on the leaves, stems and fruits - just like most solanaceous (night shade) plants.   Because of this, it is not clear whether the spikes were meant to protect the plant from humans and animals or vice versa. 

Fig. 3  Solanum pyrachantum flower.

 

 Fig. 4   Armored fruit of Solanum pyrachantum. (Photo from Rob's Plants)

 

 

Threat of Invasion

The plant is drought tolerant therefore caution should be observed when it comes to cultivating this plant since it can be invasive depending on the growing conditions.  The fruits are loaded with seeds which when allowed to mature and fall on the ground will result in an explosion of new seedlings.  Eradicating an army of plants like this, would involve a bloody battle.  :)  

 Solanum pyrachantum, although related to food crops like potato, tomato and eggplant, has been cultivated solely as ornamental plant.  And we will keep it that way! 

Spotted Bells

Fig. 1     Spotted bellflower (Campanula punctata)

Campanula punctata.   Bell-shaped flowers that dangled from slender stalks periodically grabbed my attention as I roamed my mother (in-law)'s country garden in Fortuna, California.  Campanula punctata (Fig. 1) has flowers (either white or pink) that are tinged with fine purplish dots which make them appear delicately translucent.  (These dots are the distinguishing characteristic of the species punctata).  The scalloped edges of the corolla are lined with delightful trichomes.  I suppose that they function, among others, to aid pollinators in reaching their desired destination. 

 

Fig.  2     Campanula punctata grows in the shade.

 Sun Exposure.   I observed that the plant was growing in both full sun and shady areas of the garden with no obvious growth difference.   When it comes to determining whether a plant is good for the shade or full sun areas, the determining factor is usually their water requirement.  When a gardener can assure that the plants get enough (not too much) water regardless of position in the garden, then the plants can perform well regardless of sun exposure.  The plant has soft tissues hence drainage is important in order to avoid rotting of the stems. 

Fig. 3      Showy display of white flowers

Growth Habit.  This perennial plant is a moderate grower and a vigorous self-seeder.  (I know this for sure because when I visited the garden a year ago, they were not there, but this time they were all over the place.)  The plant multiplies itself in two ways - creeping rhizomes and traveling seeds.  Regular division is necessary to promote good plant vigor.  In as much as blooming occurs in spring to summer, it is best to divide the plants in the fall. 

I brought home some rhizomes of this plant for my garden.  I imagined that they would look great in the shady "Down Under".  Unfortunately, the voles got to them before they had a chance to get established.  Sad.

 

There are hundreds of species in the genus Campanula; which one have you tried in your garden? 

Trifolium

Fig. 1    Trifolium repens 'Atropurpureum'

Trifolium repens L. 'Atropurpureum' (Fig.1) is one of many varieties of the plant that is commonly known as clover.  It is a spreading perennial plant primarily grown for its purple foliage that floats above the long spindly petioles.  This plant is supposedly valuable as a ground cover for hot and dry areas making it a good choice for erosion control. 

This plant (Fig. 1) was available at our local nursery last week and I decided to try it in my garden.  Initially, it will be planted in a container for observation to determine its growth vigor before releasing it to the ground.  One can never be too cautious about plant families that have a reputation of being weeds.  

The dark purple leaves (Fig. 2) provided the reason for this variety to be called Atropurpureum.  I am curious to see whether the color will change under higher light intensity in the summer.    

Fig. 2    Trifolium repens 'Atropurporeum'

 

This is as close as I can get to presenting you all a sprig of shamrock for luck...

Happy Saint Patrick's Day!