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. 

Guttation in Succulents

Fig. 1  Guttation in Succulent Plant:  Leaf margins of Aeonium 'Pinwheel' studded with xylem sap.

Succulents are known for their ability to hold and store large quantities of water for future consumption.  These plants, which are characterized by their  thick succulent leaves, can store large quantities of water resulting in their ability to withstand prolonged dry conditions. These plants are not commonly known to exhibit guttation - the excretion of water from the plant through hydathodes due to certain atmospheric and soil conditions.  The pictures here (Fig. 1, 2, & 3), however, show that these water-thrifty succulents can have too much water. Given the right conditions, succulents undergo guttation.

  Fig. 2  Succulent leaves crowned with beads of guttation fluid.

Fig. 3  Senecio bearing guttation sap.

Plants are amazing creatures.

Citrus Leafminer

Fig.  1   Leafminer larvae feeding in the leaf through sinuous mines.

Citrus Leafminer in the Area
Leafminers (Phyllocnistis citrella) appears to be an important pest this year in our area.  As a matter of fact, this is the first time they appeared in my garden.  All my citrus plants - including orange (Citrus sinensis), lemon (Citrus limon) and calamansi/calamondin (Citrofortunella microcarpa) - showed symptoms of infestation during late summer and early fall.

Citrus leafminer is native to Asia and has spread slowly around the world. It is relatively new in the US as it is was first discovered in Florida in 1993 and eventually made it to California in 2000 (1).  It was first detected in Imperial County - probably through Mexico.  It soon moved inward toward adjacent counties (2).  And this year, leafminer now infests Sacramento and El Dorado Counties - including my garden.

Fig. 2   Leafminer larvae: feeling agoraphobic after an opening was made on its tunnel.  

Life Cycle

 Leafminer, in its adult form, is a very tiny moth which are rarely noticed.  They are most active during the cooler time of the day as in early morning and evening - resting on the underside of the leaves of the host plant during the day.  The moth does not do damage to the plant but it lays its egg along the mid-vein of new tender leaves.  After a week, the egg hatches into a larvae and it begins to feed in the leaf creating micro tunnels that runs in a sinuous path of mines (Fig. 1).  Leafminer is most destructive in the larval stage. The once-invisible tunnels soon begin to cover a large proportion of the leaf.  At some point the larvae gets out of the mines and move towards the edge of the leaf and rolls the leaf around it -- this is the pre-pupal stage.  The curling of young foliage is the most noticeable sign of infestation (Fig. 3).  Unfortunately, at this stage, most of the damage has been done.  The pupa will live there for a few more weeks before it emerges as a moth (Fig. 4).  Female moths immediately releases sex pheromones to attract males.  Thus the cycle of life continues without delay. :)

Fig.  3   Citrus leafminer (Phyllocnistis citrella) on Calamansi.

How to Manage Leafminer

The success management depends on how early the life cycle broken. Pest when properly managed can be inhibited from spreading into a large area.  Since oviposition (egg-laying) happens only in the newly opened leaves, it is a good idea to monitor the presence of leafminer around the time of growth flush.  IPM recommends the use of pheromone-baited traps only to detect the time when males begin to fly and determine time of insecticide application. There are insecticides available for the control of citrus leafminers but timing and type of insecticide is key.  

 Depending on mode of action, insecticides attack pests at 

specific stages of  the insect's life cycle.

Here are some examples of pesticides and the corresponding stage of the insect when they are most effective:  

1.  Permethrin (e.g. Eight) and Spinosad (e.g. Captain Jack's Dead Bug) Controls the moths.  Spray only within the area where they are expected to linger.
  

2.  Horticultural oils (e.g. Neem Oil) May hinders oviposition (egg-laying) on sprayed leaves.  Repeat spraying as new leaves emerge.

3.  Neonicotinoid (e.g. imidacloprid) controls the larvae.  When the leafminer larvae are inside the "leaf mine" only systemic insecticides (such as neonicotinoid) can get them effectively. For drench application, it is important to keep in mind that the insecticide molecules take about two weeks to reach the growing points of the plant - where leafminer eggs are laid. In other words, apply before infestation is expected - when the new leaves are half-way open.  Imidacloprid when sprayed on the leaves can also move translaminary - the active ingredient of the insecticide penetrates the leaf cuticle and moves into the leaf tissues.  This means that even the larvae that is securely tucked in its tunnel becomes vulnerable.

When using any insecticide, always use recommended dosage and the recommended schedule so that we do not accidently kill unintended insects including beneficial ones.

  

Fig.  4     A magnified image of an adult citrus leafminer (Phyllocnistis citrella).   (Photo from Tirogaverd)

Other Management Tips

1.  Pruning encourages new growth (flush) on which leafminers prefer to lay their eggs.  If you can handle looking at leafminer-damaged leaves, do not be too in a hurry to cut them off because they can still continue to photosynthesize (produce food) for the plant. 

2.  High-nitrogen fertilization also result in a growth flush.  Avoid excessive nitrogen application and  use organic fertilizers or slow-release fertilizers. 

Stroll in your garden often.  If you find some leafminers, squash them.

Avocado - First Flowers and Fruit

Fig.1  Indeterminate inflorescence

At the time when I was about to give up hope of ever making homegrown-homemade guacamole, our avocado tree bloomed this year - hope has dawned.  This is the same avocado tree  that I wrote about earlier. Like all other trees in my garden I expected this avocado to bloom sometime; but because it took almost nine years before the first flowers appeared, I was surprised to see panicles (clusters of flowers in one stalk) of flowers last spring.  I guess this is the thrill of growing fruit trees from seed. 

There are two types of avocado inflorescences (flowers) - determinate or indeterminate. Indeterminate inflorescence, terminates below a vegetative bud (Fig. 1), which according to the UC-ANR, is more common in this area.  In the case of determinate inflorescence, flowers appear at the terminal end of the flower-bearing shoot.  Avocado inflorescence develops in panicles of up to hundreds of flowers.  For the tree in my garden, there were very few flowers per panicle - which is not surprising since this is only its first blooming year. Maybe the second year will be better.  

Fig. 2   Cobweb-covered panicle.

After flowers, the next thing to look for are fruits.  There was one fruit that developed. The one and only (Fig.3).  Why?  Pollination is the major determinants of productivity.  Flowers have to be pollinated prior to fertilization and fruit setting - usually, insects play a huge role in this process. Close-up picture of the flowers on Fig. 2, gives an explanation to the singular fruit (Fig. 3) on the entire tree.   The flowers were covered with cobweb prior to anthesis (period when flower is fully open and functional). Any insect attempting to visit the flowers is in for a deadly trap.  Regardless of the complexity of the avocado pollination process, this situation alone seems enough to abort pollination.

Fig. 3    The one fruit.

Lessons learned:  
1.  Under local conditions, avocado takes nine years from seed to flower.
2.  Fruiting can happen in this area.
3.  A second tree is not a requirement to pollination.
4.  Spiders can hinder pollination.  :)

Re-potting and Dividing Cymbidium - Again

Fig. 1  Cymbidium:  Winter of 2014

Three years ago I repotted my cymbidiums into three gallon containers.  This year (late spring) I divided them again after they all finished blooming; turning each plant into three individual plants. In some cases I hesitated to divide them because I like seeing multitudes of spikes (instead of two or three per plant) shooting from among the sword-like sheaths of green leaves, so I repotted them into larger containers.  One of them now resides in a fifteen gallon container.  It will be interesting to see how it will perform next blooming season.

Fig. 2   Cymbidium in  a 10-gallon container.

2010 Potting Medium

Motivated by the high cost of bagged orchid mix, I thought of making my own mix for my cymbidiums as follows:

Decomposed redwood bark (.25 - 0.5 inch)

Perlite

Handful of  potting soil

I used three years ago worked.  The plants did well - with lots of blooms and good root system.  The bark decomposed into very fine compost which I scattered along the rows of boxwood near my vegetable garden.

2014 Potting Medium

This year I used yet a different mix:  

Bark (0.5 - 1.0 inches)

Peat moss

Garden soil

With the current drought that we are experiencing, the peat moss would help retain more water allowing for less frequent watering.  Larger-size bark was used to allow good air movement around the root area.

Fig. 3  Cymbidiums lined up along south-facing wall.

Fig. 4  Newly repotted orchids.

Fig. 5    Pink cymbidiums:  Winter 2014

Fig. 6    Yellow cymbidiums

Right now, my orchids are doing well in their new growing media but it took them a while to get used to their new root environment.  I will be posing a new update come fall.

 

First Fig Fruit...

Fig (Ficus carica 'Brown Turkey')

At last my own fig tree bears fruits!  And it has a name - unlike the volunteer fig that has been planted by birds around my yard.  This one is 'Brown Turkey' which I chose because the tree is supposed to be a more compact than the other traditional varieties such as 'Mission' fig.

The fig fruit is very fascinating.  It is a synconium or an inverted fruit. The fig synconium is made up of multiple fruits that are fused together.  Each seed is an individual aggregate fruit.  It is similar to the strawberry, except the arrangement is reversed. The seeds in strawberry are on the surface of the fruit while the seeds in the figs are inside.  That description almost makes the fig a normal fruit.  But the fact that the fig flowers were never outside of the fruit makes it completely an odd fruit.  

Synconium:  the flowers open inside the fruit.  

Fig is probably among the earliest domesticated plants on earth.  It is mentioned multiple times in the Old Testament Bible as part of the life of mankind in the old days.  For example: the presence of a fig tree, is referred as one of the features of a good land (Deuteronomy 8:7-9); and the shade of a fig tree is symbolizes a place of safety (1 Kings 4:25).  Having a fig tree in my yard seems like owning a time machine that brings me back to that time in history.    

To eat figs off the tree in the morning, when they have been barely touched by the sun, is one of the exquisite pleasures of owning a fig tree.

Looking Back: Lessons Learned in Tomato Growing

Fig. 1   'Super Fantastic' tomato.

Tomato is one of the favorite vegetables in our home. Every year, we grow different vegetables.  Since we moved to this area (fifteen years ago) I cannot remember a single summer when tomatoes were not grown in this garden.  I can remember a time when my second daughter was just three and I found her in the garden her mouth bleeding and blood dripping all over her white shirt.  Or so I thought.  But to my relief, I also found tomato seeds with the red fluid oozing from her mouth. She has been in the tomato path where she ate, who knows how many, cherry tomatoes straight from the plants.  :)

As the summer draws to an end and the summer vegetable garden begins to fade, I thought I’d look back.  Everyone knows how to grow tomatoes but there are things each gardener learns through experience.  For the record, here is a list of some of the useful lessons I learned.

Fig. 2     Almost-perfect fruit set.

Optimum temperatures for tomato fruit setting are between 70 and 85 degrees F. 

Lesson 1.  Plant early in the season – protect them if you need to.
 As early as March, when other gardeners were still anticipating more frosty nights, we planted tomatoes. As a result, we enjoyed eating our own home-grown tomato salad early in the season. There is a small window in the temperature range when tomato blossoms set - and the optimum day temperature range being 70-85 degrees F. When night temperatures are cool (consistently below 55 degrees) or when day temperatures are hot (day temperatures of 95 degrees with night time temperatures of consistently above 75 degrees), fruit setting is jeopardized. Planting early prepares tomatoes for fruit setting prior to the occurrence of optimum temperatures during that season. The plant should be blooming by the time temperatures are right because this part of the country (Zone 9) heats up within a short period of time. There is nothing worse than having tomato plants that are beginning to bloom in the dead of summer. No amount of blossom spray will correct the effects of our area's intense summer temperature.

Consumption and utilization of produce is the ultimate measure of success in vegetable gardening.

Lesson 2.   Stagger planting of similar maturity-date varieties. 
This is especially important when planting determinate varieties which yield one heavy crop on a short period of time.   Planting tomato successively at two-week- interval provides a progression of harvest rather than an overwhelming amount of harvest at one time. It prolongs harvest period and makes canning even more manageable.

Fig. 3   Tomato varieties in this basket: Cherokee Purple; Super Fantastic; Yellow Pear

The soil is like a plant nanny that holds food and water for the plant. 

Lesson 3.   Recondition old soil. 

Continuously planted soils get depleted over time. Between the amount plants take up and amount water carries through run off and percolation, available nutrients in the soil can rapidly diminish. This is a mistake I had overlooked this year. Just because, my garden produced vigorous plants in the past, I took the soil condition for granted - a critical part of the garden was neglected.  Therefore, by the end of this year, I plan to cover the area with chicken manure and leaves that will fall from healthy deciduous trees. Then add a small amount of complete organic fertilizer.  This recipe will encourage microorganisms and earthworms to do their job on boosting the condition of the soil.

Tomatoes stop being productive under extremely hot and dry conditions.

Lesson 4.   Plant Tomatoes where they get late afternoon shade.
While tomatoes are a summer crop, they reach optimum production at relatively low temperatures.  When temperatures are high, the stomata close and thus halt production (photosynthesis).  In this part of the country (Zone 9) temperatures get in the high nineties up to over 100 degrees.  It is a good idea to position the tomatoes in an area where they get a relief from the intensity of the summer's afternoon sun.  Not only does the production rate is reduced, problems such as scalding, blossom-end-rot, and leaf curling become a problem. Some gardeners provide shade for the tomatoes during the late afternoon to reduce stress from high temperatures, water deficit and high radiation.

Fig. 4   Fresh from the garden.

Gardeners don't work alone, they have natural allies. 

Lesson  5.  Attract Blue Jays to the garden to eliminate problems with tomato/tobacco hornworm. 

When it comes to finding the most devastating caterpillars in the tomato garden, blue jays are the best.  It is good to encourage them to linger in the garden.  Set out some large-seed bird food such as corn and peanuts in the garden and provide a source of water for them such as a simple bird bath.   In my garden, the promise of fruits from the grapes, pears, apples and plums lure the jays as well as the mocking birds (both are great hunters of caterpillars) to stay around.  It’s been years since we had problems with tobacco hornworm.