Abutilon

Fig. 1      Abutilon x hybridum - solitary and pendent flower. (February 15, 2012)

 

New Plant for My Garden

Last fall, I bought a foot-tall blooming Abutilon plant from the Farmer's Market in Placerville. Winter is almost over and the same plant remains blooming and seemingly unrelenting (Fig.1). The plant has flower buds that come out wrapped in a blackish red calyx (Fig. 2) which eventually opens into a bell-shaped pendent flower with overlapping dark scarlet petals and even a red peduncle (Fig. 1).

Twelve years ago when there were no tall trees in my backyard, I planted my first Abutilon and I was very pleased with its vigor. Sadly, on its third year, it began to shade some important plants round it. It had to go in favor of the other ones. But because of its desirable characteristics as a plant, I bought this new plant (Fig.1) as a replacement for the old one.

Fig. 2     Unopened Abutilon flower

About Abutilon

Common names include: Flowering maple; Parlor maple; Indian mallow; Chinese lantern, etc.  They are closely related to Hibiscus (Malvaceae family).  They are occasionally referred to as "maple" because of the resemblance to the actual maple trees in the shape of the leaves being palmate.  

Abutilons are evergreen small trees that can grow up to about eight feet tall. They are fast growing  plants. Given the right conditions they can reach their potential height on the second year.   They bloom almost year round in our area. Of the numerous varieties, the most popular ones bear solitary and pendent flowers like the one I have now (Fig. 1 and Fig.2). There are some that bear flowers in panicles - dangling like their solitary counterparts.   Green Acres, the mega nursery in the area, currently offers a wide selection of Abutilon.

 

Tips in Growing Abutilon

1.  Microclimate.   Abutilons like places with a lot of light up a point when temperature interferes with its growth.  In hot and dry areas like here near the Sacramento area, the plant prefers to grow in a sheltered south-facing location.  Afternoon shade helps reduce excessive transpiration and scorching of the flowers.  On the other hand, in places with cooler temperatures and more rains, full sun would work well.  Always remember to garden with microclimate instead of the generic recommendations for your plants.

2. Fertilization.  Being fast-growing and ever-blooming,  the plant benefits from adequate fertilization.  Phosphorous fertilization during the first and second year of growth ensures a strong root system.  If it is grown in a container then regular application of a slow release balanced fertilizer is more important than those planted in the ground.  The plant is responsive to fetilization as much as it is expressive of nutritional deficiency.  Chlorosis is the first sign of nitrogen deficiency but make sure that it is not caused by insufficient or excessive watering.  In general, I withhold fertilization starting in late fall to allow my evergreen plants to rest a little. 

3.  Pruning.  The plant may be pruned to regulate its shape and size. In the spring it is best to prune the tree, removing all branches that have died during the previous season, before the temperatures warm up.  Pruning may be done anytime to remove branches that stick out of place and also to encourage branching for a fuller shrub. 

   

Abutilon: evergreen and ever-blooming perennial for the protected sunny location in the 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!

Sweet Potato

 Fig.1     New sweet potato (Ipomea batatas) plant.

Nostalgic Introduction

If anyone would make a movie about my childhood days in the Philippines, sweet potato (Ipomea batatas) would show up over and over again in the background.  Sweet potato is a must-have crop. The roots are eaten as source of carbohydrates prepared as dessert or snack food.  Although it is nutritious and readily available, it does not have the reputation as a staple food unlike rice (Oryza sativa), corn (Zea mays) and cassava (Manihot esculenta).  As a root crop it has a low acceptance possibly due to its flatulent characteristic.   The young leaves, however, have a better reputation as green vegetable.  They are cooked in stews or prepared as wilted salad.  When wilted (not over-cooked) they taste like spinach.  Believe it or not, some varieties taste better than others.   The vines and the older leaves are used as feeds. 

Growing sweet potato is very easy.  In fact the American expression "Piece of cake", can be translated in Ilocano (my native dialect) as "Kasla agmula ti kamote" meaning "It's like planting sweet potato". There was a time when the roadsides in my barrio (village) were all planted with sweet potatoes.  They were beautiful.  Here on the temperate side of the globe, there is also an increasing popularity of the Ipomea (sweet potato) as an ornamental plant mainly for its foliage.

Fig. 2   Sprouts arising from stored sweet potato roots. (January 31, 2012)

Fig. 3 A clean cut on one side of sweet potato.

Regenerating Storage Organs
Now in my house, away from the barrio where I grew up, sweet potato only shows up on Thanksgiving and Christmas.  A month ago while cleaning my pantry, I was in luck!  I found two large sweet potatoes that were sprouting.  The immediate thought that came to mind was planting material.  They have been sitting there for at least two months.  Sweet potatoes, commonly known in the US as yams, are storage organs where food and moisture abound. Because of that, the cells within the root are kept alive and capable of regeneration - starting a new plant.  This is true for most of the food we eat that come in various forms of storage organs such as bulbs (onions - Allium cepa and garlic - Allium sativum); rhizome (ginger- Zingiber officinale); tubers (potatoes - Solanum tuberosum); and corm (taro - Colocasia esculenta).  All of these examples will regenerate when the right conditions are met.  In the home, the pantry seems favorable enough to initiate new growths on such vegetables.

Fig. 4 Wet paper towel encourages root growth on a sprouting sweet potato.

Conditioning the New Sprouts.

Plants grown in the dark, such as those shown on Fig. 2 are etiolated and lanky. This, however, can be improved by exposing them to diffused light.  What I did was cut one side of the root (Fig. 3) to provide a flat surface that would rest on the wet paper towel on a dish (Fig. 4).  It has been my experience that growth of adventitious roots is enhanced by moisture - so the paper towel was kept wet at all times. 

Fig. 5     One week of exposure to light resulted in healthy-looking sprouts.

Garden-worthy Plantlets.

After eight days of exposure to light, the sprouts showed a significant change in coloration (Fig. 5 and Fig. 2).   The young sprouts begin to produce chlorophyll giving the leaves a green color.  They have grown to be more stocky and strong.  The same principle applies to potato (Solanum tuberosum) seed tubers. When their sprouts are pale, give them some time to get exposed to diffused light before planting them.

The roots  (Fig.5) look like they are ready to meet the soil but I will have to keep them inside for a little bit longer until the temperatures get warm. 

 

The Role of Sweet Potato in Another Country

I invite you to watch this video to see how sweet potato is being used to end hunger in Mozambique.

HortiCOOLture: Enormous Aloe

Fig. 1   Aloe arborescens  (February 18, 2012 Pacific Grove, California)

A. arborescens, also known as A. perfoliata var. arborescens is commonly named as Octopus plant, Candelabra aloe, or Torch plant.  The plant is multi-branched with rosettes of tentacle-like, partly concave leaves, thus the name octopus.  Like most succulents, A. arborescens blooms once a year (spring to summer).  Each rosette then sends out a terminal upright raceme that is covered with red flowers - transforming the plant to resemble the appearance of a chandelier (Fig. 1). 

According to the AHS, this plant is a native of Malawi, Mozambique, Zimbabwe, and South Africa.  Based on the size of this plant (Fig. 1), however, the California coast seems to provide favorable conditions for its growth.  

This enormous Aloe arborescens is stunning but I will not have it in my yard because its leaves are sharply-serrated. 

Boxwood: Regulating Canopy Density

Fig. 1   Boxwood (Boxus microphylla japonica 'Green Beauty') hedge.

Boxwood is a popular hedge material because it is evergreen with a dense growth  habit.   In my garden hedges of boxwood (Boxus microphylla japonica 'Green Beauty') provide walls around the lawn and divide the yard into different garden rooms.  When other plants die back in the winter, the boxwood hedges remain as strict reminders of the discipline that I have set for my yard. 

When leaves cease to be useful
Healthy leaves of boxwood remain on the plant for two to three years.  I have observed that the leaves that were cut during trimming in the spring of last year are still green and intact (Fig. 2).  Regular trimming maintains the shape of the hedges as it also promotes more branching.  However, as the new growths spread out, the older leaves get covered and deprived of sunlight.  Leaves that do not get enough sunlight become photosynthetically inactive and dependent creating an increased deficit on food supply for the ever increasing foliage.  Eventually, the dependent leaves get less and less ration until the plant decides that they are no longer useful for the plant.  Plants in general, have a very accurate accounting process in this regard.  When a leaf if considered unproductive, the plant will separate it by blocking the passage way for food supply until the leaf is completely dead and detached.  Technically, this process is called abscission.

Fig. 2  Boxwood retains its leaves for more than two years.

When less is more
 
To maintain a healthy boxwood shrub or hedge, the ratio of the active to inactive leaves need to be increased.  As a general rule, all leaves need to get exposed to sunlight. This can be achieved by thinning the branches to allow sunlight to reach into the depths of the canopy.  Thinning also improves air circulation within the hedge thus preventing the growth of diseases. 

Tips for Thinning Boxwood
1.   Cut off branches from within.  From the dense sides of the hedge, cut into the canopy, six to eight inches long - one branch at a time.  Repeat the process throughout until the desired density is achieved.
 
2.  Make way for light and air within.  The process creates open spaces or holes for sunlight and air to penetrate the interior canopy of the plant.  With time, new branches will grow from the inner canopy making the plants healthier and less likely to be infected by fungal diseases.

3.  Change canopy density.  While thinning, keep in mind to maintain the shape of the plant.  Thinning is not intended to change the size or shape of the plant.  Instead, it is the removal of excess branches from a crowded canopy. 

4.  Thin prior to the next growth spurt.  Boxwood put on new growth in the spring and fall.  When the need for thinning arises, it is best to do it before the next growth spurt.  It is easier to spot overlapping branches before the older branches get overgrown by the new ones. 

In my garden, some parts of my hedges are in need of thinning.  One of these days, with my sharp pruners, I will have a date with my boxwood.

It takes years to grow a good hedge of boxwood.  Thinning contributes greatly in keeping them healthy and strong.

Broken to Beautiful

Fig. 1     Foxtail ferns (Asparagus densiflorus 'Myers') are a common sight in my garden.

One of my favorite container plants is the Foxtail fern (Asparagus densiflorus 'Myers'). In a pot (Fig. 1), I can move them from one place to another in the yard where an instant color is needed.  Foxtail ferns develop vigorous root system along with water storage organs.   This feature makes the plant a celebrity-drought-tolerant plant.  As a container plant, however, the same vigorous roots system causes a slight draw back.  The plant gets root-bound easily.  

Fig. 2     Pressure from the foxtail fern (Asparagus densiflorus) roots broke the terra cotta pot.

The problem.  In my garden the super-powered roots of the Asparagus densiflorus defied the shape of its container pot (Fig. 2).  It is very obvious that this plant is in a desperate need of more room to grow.   Dividing the plant at this point would only mean breaking the already-broken pot.  I was not sold to this idea.

Fig. 3     Sempervivum-pups in a row.

The Solution.   I cut off some of the roots that have been dried out from being exposed through the crack - to make room for a little bit of potting soil.  Using sempervivum that are available from my garden, I planted the crack with similarly drought tolerant plants (Fig. 3).

Fig. 4   These plants (Sempervivum - hen and chicks) look like they have been there all the time.

The outcome.   The crack no longer looks like a disgrace (Fig. 4).  As soon as the temperatures get warmer, these "ever-living" runners will send their own roots into the thicket to join the foxtail fern's roots.   Today, I saw a bird trying to get peck on the new plants which tells me that a wire around the plants might be necessary for the time being. 

Finally, to avoid such thing from happening in your gardens, divide potted foxtail ferns at least every two years.  For bulbous containers like the one I used here (Fig. 2 and Fig. 4) division is even more critical because at a certain point the plant cannot be pulled out without damaging the container.    

 

A little bit of imagination can transform some problems into blessings.

Gardening and Microclimate

Fig. 1  Mature plant communities at Filoli Gardens.

Gardening is all about harnessing microclimate.  After so many years of studying, observing, and putting all techniques learned into practical use in growing plants, I've arrived to the conclusion that the complexity of gardening boils down to understanding microclimate.  The magnitude of the effects of genetics and management practices on the overall success of gardening can be enhanced or diminished by the immediate growing environment - microclimate.  Microclimate is the unique condition within the immediate surroundings of a given small area. It takes into account the interaction of the following factors: light (intensity, duration), temperature, wind/turbulence, moisture, soil condition, and topography.  It is affected by the presence or absence of structures such buildings, pavements, trees, slopes, orientation, and plants around the area.  

Gardening on the basis of the USDA Hardiness Zone alone is not enough.  Every gardener knows that different plants require different conditions for optimum growth.  The plants we buy from nurseries come with labels that indicate the most basic and generic condition for growth.  The terms full sun, partial sun, partial shade, shade, all suggest a preferred microclimate for the specific plant.  Some plants need direct full sunlight while others prefer attenuated sunlight light allowing them to perform best under tall trees (Fig. 1).  However, one must consider that a full sun in Seattle may not the same as that in Sacramento.  

Fig. 2  Eastern side: Growing trees and hedges affect the amount of sunlight and wind turbulence in the garden.

Microclimates in My Backyard.  Even small backyard gardens like mine have several distinct microclimates.  The eastern side (Fig. 2) of the house is a lot different from the southern side (Fig. 3).  The former gets an early but short exposure to sunlight while the latter gets a later, prolonged and higher-intensity sunlight.  At the western side of the house light reflects from the white wall and wind circulation is limited because of the close distance between the house and the fence.  The north side is still another microclimate where the sun comes only late in the afternoon.  The best performing plant on this side is the Cecile Brunner rose which has extended itself to reach the top of the roof where it can get enough sunlight  (Fig. 4).  My garden is now a lot shadier than it was twelve years ago.  The trees have matured and the place where I used to plant strawberries now gets only two hours of  dappled sunlight during a summer day.  (One good effect of the lack of sunlight is that there are no more weeds growing there.)

 

Fig. 3 Southern side of the garden.

Fig.  4  Northern side: Cecile Brunner rose

  

Fig.  5.  Location for a bench -  shade or sun?

The Bench Comparison.  In gardening, finding the right microclimate is like finding the right place for a bench (Fig. 5).  Depending on the location, one can either enjoy sitting on it or suffer.  But then again, it also depends on the goal of the person sitting on the bench.  My friend, Sue, would like her bench to be in the sun while I like it to be in the shade.  With restraint, both bench positions are good depending on the desired effect.  

 Crassula argentea 'Compacta' under two microclimates. 

Fig. 6   Grown on the eastern side of the yard.

Two years ago  I bought a compact mini jade plant (Crassula argentea 'Compacta') in a 3 inch pot.  Since then the plant has grown and been divided into two separate plants in 6" pots.  One of them (Fig. 6) was located on the east-facing side of the yard.  The other one (Fig. 7) was positioned in the south-facing side of the yard where it was exposed to prolonged direct sunlight. It was definitely hotter on this side of the yard; the soil also dried up faster than its east-facing counterpart.

Fig. 7  Grown on the the southern side of the yard.

There was a sharp contrast between the two plants when it comes to color.  More sunlight (Fig 7) resulted in yellowish leaves with very pronounced red leaf margins.  Shorter direct sunlight resulted in darker green leaves (Fig. 6).  As long as the needs of the plants are all met at the right amount, the two plants function normally but to the naked eye, microclimate within their growing area is reflected through their coloration.   These are occurrences that we so often take for granted.  But if you think about it, a gardener can actually manipulate the color of these jade plants to suit their preferences by strategically planting them in the right microclimate. 

Spring is right around the corner and planting season is here.  Make sure to re-acquaint yourself with the ever-changing microclimates around your garden.  It is the most important consideration in your choice of plants and even timing of activities in your garden.

"Sufficient knowledge of your microclimates will help you understand your gardening successes and failures."