Sophronitis Coccinea Care Questions

[Mapp]

Hi all,
As I type this I have two Soph. Coccinea seedlings on their way to my house. I know they’re a notoriously finicky species of orchid (picky about water quality, humidity, temps etc.) and I’ve done my best to do my homework on their cultural requirements before purchasing them, but I still have a few questions that I haven’t been able to find answers to on my own.

I’ve found some contradictory information on watering, some sources say they must be kept damp at all times and do not tolerate drying out well, while others say you should treat it like most other Catts and allow it to dry between waterings. I grow on a south-facing windowsill, with a humidifier running 24/7 (maintaining humidity of 60-70%) with a little fan running most of the day for air circulation. Daytime high of ~73° and nighttime low of ~64°. Because they’re seedlings (not sure how small, as they haven’t been delivered yet) I’m inclined to keep them on the moist side, but with my cooler temps and highish humidity I’m wondering if that might be a recipe for infection.

I’m also curious if my tap water is acceptable. I have what I could consider very good tap water, after running it through a Brita filter it gives a reading of 65-75 PPM on a cheapo EC TDS meter. Will this plus occasional weak feeding be an acceptable amount of desolved salts, or should I consider using distilled/RO? I have a coccinea primary cross (s. coccinea x l. pumila) that had some issues with root tips going black and dying off but that seems to be resolved now that I’ve switched brands of fertilizer and reduced the amount and frequency of the feed.

I visited J&L in Connecticut a number of years ago, and they had some of the gorgeous tetraploid clones of these plants in bloom and I’ve been in love ever since! I’ve done my best to scour these forums for information on them, and there’s a fair bit of it but any tips you may have to help me not kill these beauties would be much appreciated!

[SouthPark]

Originally Posted by Mapp

while others say you should treat it like most other Catts and allow it to dry between waterings.

The nice thing about having multiple orchids of the same kind allows testing to be done. You could go down this path of allowing dry out between watering.

We definitely know that choice of media plays a role in the amount of watering. If the catt-type orchid just naturally has stick/pencil-like slender pseudobulbs, then growing them in volcanic rock could mean watering every day.

And maybe every few days, could possibly skip a day of watering - to dry out - just to cut down on possible unwanted things occurring in the pot.

[rbarata]

ORIGIN/HABITAT: Brazil. Plants grow in coastal mountains on ridges lying near and parallel to the coast from the state of Santa Catarina northward through the states of Paraná, São Paulo and Rio de Janeiro. After a brief interruption, plants are found further to the east in the Organ Mountains and then to the north in the coastal mountains of Espirito Santo. Within this region, the habitat may be discontinuous for miles in some localities, but it ultimately re-appears with plants almost always growing on seaward-facing slopes in a band some 2-3 mi. (3–5 km) wide at elevations of 2000–3000 ft. (610–910 m). The moist, southeast tradewinds in this region are lifted along the face of the coastal mountains and condense into clouds and fog with fine mistlike rain. These conditions occur almost daily after 4 p. m. and continue through the night, even during the dry season. Because of this, the habitat is very moist with moss covering everything. The average trees in these moist forests are 15–50 ft. (5–15 m) long and 4–12 in. (10–30 cm) in diameter. Sophronitis coccinea grows on these moss-enshrouded saplings and small trees from near the ground to almost the top. -- Source: Charles Baker

More on this, also from Charles Baker:

HUMIDITY: 80–85% year-round. WATER: Rainfall is moderate to heavy most of the year, with a slightly drier period in winter. Cultivated plants should be kept moist and never dry out completely. Care should be taken, however, to ensure the medium does not become stale or sour.

I believe it may give some hints about watering