Winter-blooming Chains of Glory a.k.a. the Lightbulb Plant

After the holiday Paperwhite and Amaryllis flowers decline, there is usually a dearth of flowers at the Red House Garden until the blooming of earliest spring bulbs.  This year, however, my Chains of Glory is in bloom.

Chains of Glory plant

I bought this Chains of Glory plant, or Clerodendrum smithianum, three years ago from Logee's, a well-known nursery down in Connecticut that specializes in rare and tropical plants.  (They are known as a mail-order nursery, but if you ever have the chance to visit their greenhouses, it is well worth the trip!)  I am extremely negligent of my houseplants, so the fact that this one has survived to tell the tale is an indicator of how hardy it is.

Clerodendrum smithianum

Clerodendrum smithianum is actually a shrub or small, multi-stemmed tree native to Thailand that can grow up to ten feet tall.  For use as a houseplant, it is recommended that it be pruned after its winter blooming to keep it a more manageable size.  My plant has managed to stay nice and small thanks to two battles with spider mites and one unexpected and drastic pruning by a plant-hungry cat.  (Like I said, this plant is impressively hardy.)  When a mature plant is in full flower, the effect of multitudes of cascading flowers makes it easy to see where it gets its nickname 'Chains of Glory'.

Another common nickname for this Clerodendrum is the 'Lightbulb Plant', which I personally love.  Before the flowers fully open, they do rather look like little white lightbulbs.  I've also seen it called 'Indian beads'.

Lightbulb Plant

Clerodendrum smithianum is hardy to zone 9b, and prefers full sun to part shade, though direct afternoon sun can burn the leaves.  I have mine on a shelf near a south facing window.  It is a very long blooming plant as the flowers slowly open, starting with the top and working their way down. Mine has been in bloom for a month and is still going strong.  It is said that it can bloom twice in winter, so I am excited to see how long it will be in flower.  When grown in warmer climates, it can bloom for months.  It is a great plant for a hanging basket or as a patio plant, and it is sometimes even grown as a bonsai.  Chains of Glory likes fertile, well draining soil, and the soil should look dry before watering again.

Clerodendrum smithianum

Many Chains of Glory plants have both dark red stems and red star-shaped sepals which are quite showy in contrast with the white flowers.  My stems do age red, but the flower sepals of my plant are all light green with just a touch of red on the tips.

As far as botanical nomenclature goes, Clerodendrum smithianum's past appears to be quite mysterious.  Some online resources seem to think that C. smithianum is synonymous with C. schmidtii (also syn. C. hastato-oblongum C.B. Clarke).  This plant was first documented by E.J.Schmidt, a Danish oceanographer and naturalist who collected plant specimens from Koh Chang Island in Thailand in 1899, and catalogued by C.B. Clarke, a British botanist who worked at Kew.

Clerodendrum smithianum = Clerodendrum schmidtii ?

Other online resources, on the other hand, seem to think that C. smithianum is synonymous with the more similarly named C. smitinandii, a different species of Clerodendrum that was collected a few decades later by Tem Smitinand, a Thai forest botanist, and likely categorized by the American botanist H.N. Moldenke.

Clerodendrum smithianum = Clerodendrum smitinandii ?

All of these are known as 'Lightbulb Plant' or 'Chains of Glory'.  Is my Clerodendrum smithianum just another name for a different species, or is it its own separate one?  If anyone else knows, let me know! 

(p.s. If you would like to go down the rabbit hole with me, there is a paper published by botanists in connection with Chulalongkorn University that describes and illustrates the differences between the two other species.  My C. smithianum seems to resemble C. schmidtii the most to me, but I am no botanist.)

**UPDATE: I e-mailed Logee's and they replied back that it is, indeed, the same plant as C. schmidtii.  Mystery solved!

Whatever its origins, having a plant that blooms in the depths of winter is most definitely a thing of beauty!