Dendrobium culture: Dendrobium cucullatum, getting the plant to produce really long canes

 One of my favorite Dendrobium has been Dendrobium cucullatum, also known as Den pierardii, and Den aphyllum.  This species does well in my climatic conditions, so much so that all you need to do is attach it to a tree and it will grow and bloom with little care.  I have had plants of this species for many years.

In photos of this plant in Asia I noted that the plants were in many cases much thicker and longer than my plants and produced more and larger flowers.  After observing my plants, I concluded that the issue was that the plants were in baskets and pots that dried too fast for this species.  As a result, a plant that could potentially produce a six feet cane, would top out at a third of that size.

To rest this hypothesis, I put a three-cane plant of this species in plastic soda bottle that was cut in a way that there is a water reservoir at the bottom of the bottle that the roots of the orchid can reach.  I also made holes that allowed plenty of air to reach the roots, this is to avoid rot.

The results were highly gratifying.  The plant produced a five and a half foot cane, much thicker than usual.  In the second year in the pot its on its way to produce an even larger cane.   This year it bloomed with many flowers, sadly marred by thrips.  I expect that next year it will produce even more flowers.  I have a nasty surprise prepared for any thrip that might show up to eat the flowers.

In the future, I plan to make a basket that will allow for four or five canes to grow together.   Given the large size that such an arrangement would achieve the basket and pot would need to be quite strong not to be turned upside down by the sheer weight of the canes.

On a final note, the size of a plant is influenced by many things, light, fertilizer, watering, genetics, temperature and others.  It may be that some plants of this species are naturally small.  The plant I used for the test came from a parent that I knew can produce at least six foot long canes and maybe longer if given optimal care.  So don’t be frustrated if you plant doesn’t suddenly becomes a giant.

Soft cane Dendrobium, end of growing season flowers

Dendrobium Bohemian Rhapsody, end of growing season flower

Dendrobium Bohemian Rhapsody, normal flower

Dendrobium anosmum, dark colored variant

Dendrobium anosmum var. huttoni

When the growing season ends for soft cane Dendrobium, the canes stop growing and produce a terminal leaf that is smaller than previous leaves.  But sometimes, instead of a terminal leaf, the plant produces one or more flower buds.  I have seen this happen in Den. anosmum. Den. pieradii, Den. loddigessii and Den. Bohemian Rhapsody.  These end of season flowers can be larger, differently shaped and brighter colored than flowers produced during the normal blooming season.  I don't know why this happens.  Some people, particularly those that have plants that have never bloomed, can take these flowers as a normal blooming event, but it isn't.  The flowers can sometimes be significantly different from typically shaped flowers, with a prominent raised area in the middle of the lip and pointy sepals. This variation can cause confusion as to the identity of the plant, on the part of growers whose plants otherwise have never produced flowers.  At times the flowers can be deformed or crowded in a bunch at the tip of the cane.  I don't find the appareance of these flowers a cause of concern as those of my plants that produce these flowers from time to time, bloom well when their blooming season comes around.

A small pendent Dendrobium hybrid, Dendrobium Adastra x Den. parishii

Dendrobium Adastra x parishii

Dendrobium Adastra x parishii

Dendrobium Adastra x parishii

Dendrobium Adastra

Dendrobium anosmum

Dendrobium cucullatum

Dendrobium parishii

I brought this small Dendrobium hybrid at a huge Spring orchid show in 2009 that was held at Plaza Las Americas, the largest Mall in the Caribbean.  One interesting feature of these shows is that every year a few new and interesting plants are brought in, sold in quantity, and then never seen again for sale.   Because this has happened a number of times I am always on the lookout for orchids that I know are rarely exported.  This little Dendrobium is one of those rare and exciting finds.

This little plant combines the genome of three of the most outstanding species of Dendrobium of the section Dendrobium.  This orchid is the result of the cross of Den. Adastra (anosmum x cucullatum) and Den. parishii.   It is interesting to note the flower of this hybrid doesn’t resemble too closely any of the parents and has a unique charm all of its own.  One surprising characteristic of this plant is its small size.  The canes of my plant are between 12 and 15 inches long, pretty small considering than a local anosmum can easily produce five foot canes and I have some clones of cucullatum reach more than six feet long with ease.  It appears that the influence of the parishii parent has resulted in a reduced cane length in this hybrid.  But I must confess the size of this plant might have also been influenced by the way I culture it. 

One vexing problem I have had with parishii derived hybrids is their vulnerability to cane rot under my local conditions, something that also plagues my parishii plants.  However not all my parishii hybrids are equally affected, those that are in baskets with excellent drainage fare the best, those in pots fare poorly.  Because I didn’t want to lose this plant to rot I put it in a tiny basket with just enough moss to give the roots something to hold but not enough that it would stay sopping wet for hours.  As a result the root ball of this plant is comparatively puny for its size.  But since after three years under my care it has now shown itself to be quite hardy I plan to move it to a larger basket where it will be able to develop a larger root ball.  Unfortunately it has shown no inclination to produce two canes at the same time as anosmum sometimes does and its quite stingy producing keikis having produced just two so puny that I will wait until they have two canes to remove them.

As far as culture goes I grow them like I grow my anosmum except that this one is kept in a shadier location until I have more plants and can test them for resistance to several hours of full sun exposure.  Indications on growing anosmum are located elsewhere in this blog, a link can be found at the bottom of this blog page.   Compared with Adastra, anosmum and cucullatum this orchid is a relatively slow grower.  The canes sometime have slight sidewise twists, an odd feature that none of the parental species show under my care.

The flowers of this hybrid have a better shape and presentation than the flowers of any of its parents and the pink color is outstanding.  But sadly they are not scented and they are produced in limited numbers.  The relative small flower count might be due the way I grow it so the flower number will probably increase significantly if I expose it to more sun but that will be tested in the future.   Personally I would love to see a flower with the shape and color of this one but with a size comparable to the flowers of anosmum which can be four inches wide.  I sometimes wonder what would come out if someone would cross this plant with Dendrobium primulinum var. giganteum which has an enormous lip with a spectacular orange coloring in the center.  Alas it is a fantasy at this moment but, you can always dream!