Resources Discussed at the August 2015 Jacksonville Orchid Society General Meeting

At last night’s General Meeting of the Jacksonville Orchid Society, our “Panel of Experts” covered a broad range of topics. References for newcommers featured prominently. Following are several links that I’ve found useful. – “Internet Orchid Species Photo Encyclopedia” – This is my first stop when I’m looking for online information about a particular orchid species. – “ORCHIDS WIKI” – This is often my second choice for orchid information online and often fills in gaps that aren’t addressed by – “Cattleya Source Wiki” – I recently came across this source, so only time will tell whether I continue to use it, but it has proven useful so far. – The website of the “Royal Botanical Gardens” is rapidly becoming one of my favorite resources. While it covers flora in general, it also does a wonderful job describing orchids. Take a look – you’ll be pleasantly surprised. As an example, I sold a Dendrobium aphyllum keiki last night at the General Meeting. Searching yields Take a look and you’ll see that not only is the origin of plant well described, but for our interests – its care and culture are well described as well. – Grower’s Choice and Hydroponics store in north Jacksonville. Located in two Jacksonville locations (, it’s easily accessed and sells both “Hydrotron” and “Plant It” in 50L and 45L (and smaller) bags at reasonable prices. Both products are small fired clay spheres with Plant It retaining moisture 3 times as long as Hydrotron (see “Replacing Hydrotron” in the January 2014 edition of the JOS “The Bulletin” –
Don’t forget to search Google as well. It will often yield clues and information that other sites don’t provide.

Media Considerations – Hydrotron is Dead! Long Live…?

Since the summer of 2013 and earlier, the use of “Lava Rock” as an orchid medium has been actively discussed in the orchid community in general, and among members of both the Jacksonville Orchid Society (JOS) and Saint Augustine Orchid Society (SAOS).

My interest is a result of searching for a Hydrotron replacement after closure of the company that made the product for 27 years. In doing so, I’ve found two easily available replacements, Lava Rock and PlantiT, both of which I’m evaluating. There are other replacements available as well, but these can be found in the local area with Lava Rock being clearly the cheapest.

At this time, I’ve only heard of one person using PlantiT, which is available in Jacksonville at Grower’s Choice ( While I don’t yet have enough data, my initial assessment is that PlantiT, although smooth in configuration like Hydrotron, is far more water retentive than Hydrotron or Aliflor. In my own adhoc testing (decidely non-scientific) PlantiT appears to remain wet 2-3 times longer than a comparable quantity of Hydrotron. PlantiT is also far more dusty than Hydrotron out of the bag and should probably be washed before use. Unfortunately, while using PlantIt, I’ve already lost one orchid (a Cattelaya type) to rotted roots. Moreover, when examining the media I noted it was exceedingly wet, although the plant had been watered two days previously.

Regarding Lava Rock, Cortney Hackney and others report good results and I can make the same report as well.  In my case, both Dendrobia and Cattleya appear to do well with robust root growth under my growing conditions.  Successful use of Lava Rock with orchids is reported elsewhere on the Internet as well.  Tom of the Angraecums website ( and on Facebook at reports generally good results with Lava Rock, but also notes that in larger pots (8 inches and larger) the center may be too water retentive.

At the moment, it appears Lava Rock has the nod as a replacement for Hydrotron in many of my applications. How about yours?

Dendrobium blumei

The Jacksonville Orchid Society recieved a number of orchids from the wife of one of its late members and I picked this up more out of curiosity than need; plus, the price was right.  It vaguely reminded me of a Dendrobium crumenatum with its furrowed pseudobulbs, but I really didn’t know what it was.  Members of the Florida Orchid Grower’s Facebook community properly named it as Dendrobium blumei, a warm to hot growing orchid which will grow nicely in my conditions.

Dendrobium blumei - Sep 2013When I brought it home, it was desiccated and I didn’t have much hope for it.  However, after placing it in my “wet room” where it was watered twice a day, I was rewarded with this bloom after a few days.  In the shape that it was in, I couldn’t help but think it might be on a ‘death-ride’ and producing its last bloom in an effort to get fertilized before perishing.  That was last week.  A week later, I’m again rewarded with a new blossom, which gives me hope that I may be able to save this orchid. This is a small blossom, 1.7cm vertically, but nicely fragrant.  It reminds me of honey, but others suggest something more towards lemon.  Unfortunately, the blossom will only last a couple of days.