Paphiopedilum Sanderianum exactly the same size as one year ago

A young Paphiopedilum sanderianum plant

     My Paph sanderianum recently shed a leaf, revealing that the bulge I had noticed last month was simply a root nub.  With the loss of this leaf, the orchid returns to exactly the same size it was when I first received it over a year ago.  Since last September, it has shed two leaves, and completed growing two new ones. I'm not sure if this is what to expect from the species, but at this rate, I don't know how it will ever reach blooming size.  Maybe the calcium supplements I added last month will kick in and help the newest leaf grow longer than the previous leaves.  Otherwise, this orchid is growing new leaves just fast enough to make up for shedding the old ones. 

Supplementing Paphiopedilum sanderianum with calcium

Paphiopedilum sanderianum (not yet blooming sized)

     Paph sanderianum is a calcicolous species; the term refers to plants which thrive in soil that is rich in lime.  In nature, Paph sanderianum orchids are found growing on limestone cliffs in Borneo.  Limestone is composed of different crystal forms of calcium carbonate.  In practical terms, this means that Paph sanderianum can benefit from calcium supplementation when grown at home.  

     Since the media I use for my paphs  does not contain any calcium, and New York City tap water contains rather low levels of soluble calcium, I wanted to try adding some calcium supplements. However, finding clear directions on how to do this proved difficult.  There is plenty of references to some paphs benefitting from extra calcium, and the most common method of supplementation I could find involved adding crushed limestone or oyster shell directly to the potting media.

Using crushed egg shells to supplement calcium for paphiopedilum

     Now I don't have any access to limestone or oystershells on hand, but I did have leftover egg shells, which are 95-97% Calcium carbonate crystals.  Although CaCO3 has very low solubility in water under non-acidic conditions, a little can go a long way.  

     I boiled the empty egg shells to get rid of all remaining egg whites, and peeled off the membranes covering the inside of the shells.  I then used a coffee grinder to crush the egg shells into small pieces, which I could sprinkle on top of my paph's potting media.  

     Unfortunately, I can't think of any way to make this more scientific.  I can't readily measure soluble calcium levels before or after supplementation, and with one plant, I can't attribute any changes in growth as a benefit from adding egg shells.  In addition, while writing this post, I remembered that my Paph Sanderianum had rocks in it's old media, which I had saved and mixed into fresh media when I repotted the orchid back in April.  It is very possible that those rocks are limestone gravel. To avoid accidentally overloading on the calcium, I don't plan to do this more than twice a year at most.

     In unrelated news, the Paph sanderianum is growing a new leaf.  It also has a mysterious bulge at its base which may be either a new root or a new growth, either of which would be really great news.

Paphs grow new leaves

The too-tall fan grows taller

    I was hoping for a bud, but the growth on my noid paph is clearly a new leaf.  I bought this orchid in bloom around July of last year, and it is in good health.  If I'm lucky, it will rebloom for me in the summer.  The orchid has been a fast grower for me, so there is still time for it to finish the new leaf and start on a spike.

     There's a chance that it's not getting sufficient light to flower (which might also explain why the new growth has such a ridiculously tall 'stem').  My paphs and phals are growing under a daylight sunlamp, which I now suspect is not bright enough.  I've ordered a new fixture of T5 fluorescent bulbs, which will hopefully arrive soon.

New leaf on paph sanderianum first became visible about 2 weeks ago

   

     The new growth from paph sanderianum is good news.  It is a young plant which needs to get much bigger before it can hope to bloom.  I've read that sanderianums usually need to develop multiple growths before they flower, and I'll be keeping a hopeful eye out for that.  When I bought the plant 6 months ago from Marlow's Orchids, he had them listed as 2 years from blooming size.  If it grows well, I can hope to see the start of a new fan by the end of the year.

Repotting Paphiopedilum sanderianum

Young Paphiopedilum sanderianum plant

    It is a testament to the Paph sanderianum's slow growth that this is the first time I am writing about this orchid since I introduced it when starting this blog.  I've had the orchid for about 6 months now, and all it's done is finish growing a new leaf.

Another leaf?

     Now there is a hint of something new pushing out from the crown; it is almost certainly another leaf.  Bolstered by the new growth and the incipient Spring, I decided to finally repot the orchid for the first time.

     I was immediately struck by how dark the paph's roots are (much darker than those of my noid paph).  Most of the roots seemed healthy, but I didn't notice any new growing root tips.  There were however several broken roots, which I trimmed off before returning the paph to its pot.

Paph sanderianum roots after trimming

The old paph potting media

     I noticed that the old paph media had rocks mixed in with the bark and perlite.  I guess the rocks help increase the drainage of the media.  Since rock doesn't degrade like bark does, I picked out the pebbles and mixed them in with fresh media, and used that to repot the orchid back in its original pot.

Paphiopedilum Sanderianum

     Who can resist the allure of 3-foot long flower petals?  I first heard about this plant while searching for my den victoria reginae, and ordered it on impulse from the same vendor.  Adult specimens of this species are obscenely expensive, selling for hundreds of dollars.  So instead I purchased this juvenile plant which is supposed to reach flowering size in about 2 years.  Its current leaf span is 16 inches, and the paph sanderianum has proven right its reputation as an infamously slow grower.


     The plant arrived with one yellowing old leaf which promptly fell off, and a about an inch of a new leaf poking out of the crown.  Over the last 4 months, little has changed except for the very slow growth on the newest leaf.

Now about 4 inches long

     The pale green coloring at the base of the new leaf indicate that it is still growing, as it should be.  The older leaves are approximately 9 inches long and since this is a growing plant, the newer leaves should all be larger than their predecessors. 3 inches of total growth over the 4 months that I've owned this orchid make for a study in patience.  Compare this to my paph NOID, which has nearly doubled in size over a comparable time span.  Blooming this one is going to take a long while.