I'm getting ready to repot my Sophronitis orchids, which are currently growing in coconut husk chips. They seem to be doing fairly well since I've been watering them more often, but I have seen them grow better in the years past. It probably is that the medium is breaking down and the roots are not as happy any more. I think the timing is good, since Sophronitis show active growth in the fall and winter, before they flower.
I have read several posts on the internet that some growers have had success in growing Sophronitis coccinea and Dendrobium cuthbertsonii in perlite only. Since perlite is readily available at my nearby nursery, this technique is quite attractive to me. Additionally, perlite does not break down, since it is an amorphous volcanic glass. Moreover, perlite retains moisture well while also providing valuable air spaces, which is key to good orchid root health.
It appears that the growers using perlite use a semi-hydroponic water culture. Simply, this is letting the orchid pot sit in a shallow reservoir of water such that the perlite draws up water by capillary action (water creeping up due to water tension). As the moisture evaporates from the perlite, the reservoir replenishes the water. The added benefit of this method is that the evaporation decreases the temperature in the roots, which is benefitial to many cool growing orchids, such as Sophronitis, some Dendrobiums, Masdevallia, Dracula, and some Odontoglossums, to name a few.
I will pot up a tray of the Sophronitis orchids and the few Dendrobium cuthbertsonii that I have to test out this new technique. I'll post pictures of the repotted orchids once I finish this task. In the mean time, I have to decide if I will use clay pots or plastic pots. I want to use clay pots for the added evaporation, but the one major disadvantage of clay pots is the build-up of salts on the surface of the pots, which is problematic with poor water quality. Stay tuned.
This is Stanhopea nigroviolacea. This species is very similar to Stanhopea tigrina, which I wonder if they are not the same species. But since my tigrina blooms a little earlier in the year, there are some differences. The two species have almost identical fragrances. The smell is very strong and can perfume the whole area intensely. It smells sweet like candy and fruit with a warm vanilla undertone. It may be too cloying for some people. This orchid opened yesterday and probably will finish in a few days, especially since it is so warm now.
This is Paphiopedilum St. Swithin, a cross between P. rothschildianum and P. philippinense. Unfortunately, this has been blooming for a few weeks now so the flowers are a bit past their prime. I should have grabbed a photo sooner. I had this orchid indoors over the winter last year and moved it outdoors in the spring. I haven't decided what to do yet for this winter, but I am inclined to leave it outdoors with some protection.
This is Miltassia Dark Star 'Darth Vader'. This is another orchid that blooms reliably. There are probably a few dozen flowers getting ready to flower, but this is the first to bloom. Each flower spike can have up to three or four flowers and the plant can have a dozen spikes. This orchid does very well in the coastal climate and tolerates the winter cold very well.
This is Laelia crispa. I've had this orchid for a few years and this is the first time it is blooming for me. Normally, this species blooms with about four flowers on a upright stem in late summer. This orchid has been growing outdoors all this time, so I can safely recommend this orchid for temperature as low as 40 degrees.
This is Laeliocattleya Wrigleyi, a cross between Laelia anceps and Cattleya bowringiana. This is another reliable bloomer that blooms about his time of the year. I think I may have seen this bloom more than once per year. Again, this orchid can tolerate the winter low temperatures, owing to the Laelia anceps heritage.
