Masdevallia mystery leaf loss, multiple plants, help! - Orchid Board

braxtonds · #1 01-26-2016, 01:05 PM

I have a mystery on my hands and I need help solving it. I moved all of my orchids down to a new basement setup that I just completed about 2 months ago. It is two very large tables with LED lights overhead (no heat produced) and a fan for air circulation. The whole basement is stable in temps as far as I can tell, I go down at dif times of the day and it's always the same temp. I grow mainly masdevallias and cattleyas but it's the masdevallias which have now had all the problems.

Many of my masdevallias mysteriously are dropping alot of leaves. Much more than normal and I have even lost a few. Some of the leaves are turning yellow and some are turning mushy and some are turning dry and crispy. But this has only happened in the last 3 days, everything was great with lots of growth beforehand. Masdevallias are notoriously picky and any changes can cause leaf drop, believe me I already know this. But I think something pretty major happened to cause many of them to react in this way.

I'm wracking my brain: did I underwater? overwater? was there a sudden drop or rise in temps? We turn the heat down at night to 62 and raise it during the day, could that have an effect in the basement? I also added slow release fertilizer to every orchid about 3 weeks ago (but this is not a new treatment, this is what I normally do every 5-6 months or so.) Oh, one more mystery piece; we also raise worms for compost in the basement and there was a mass suicide (many, many crawled out of the bins to the floor) at the same time, which may or may not be related.

I know that changes in culture can do this and moving to the basement has been a huge learning curve, new temps, new water schedule, new light levels. But it's been a few months already and this is all very sudden. Any ideas would be greatly appreciated! Thanks

wintergirl · #2 01-26-2016, 01:23 PM

Most Masdies prefer shade. Many times if they are too wet you get black spots. I wonder about air quality if your worms are having a problem at the same time.

estación seca · #3 01-26-2016, 01:26 PM

What is the humidity? Any chance of carbon monoxide?

braxtonds · #4 01-26-2016, 01:31 PM

I just bought a humidity and thermometer. I will set them up and get the numbers later. As for carbon monoxide, I sure hope not, we have meters and they didn't go off the last couple days.

Subrosa · #5 01-26-2016, 01:53 PM

From converting many reef aquaria over from fluorescent lighting to LEDs I have learned not to trust my eyes in regards to determining brightness. LED fixtures that don't appear as bright to the human eye as the fluorescent fixture they replace can badly light shock corals. I have no doubt the same is true for plants.

braxtonds · #6 01-26-2016, 02:04 PM

Are you suggesting that the lights are too bright or dim? I have 3x 30W White and 1x 30W Red evenly spaced over an 8ft long table around 4 feet above the tables. How can I tell the strength of the lights?

Subrosa · #7 01-26-2016, 02:11 PM

Light shock occurs from a too rapid increase in light. I always keep LEDS dimmed down at first unless I'm moving sun lovers in from outside.

Paphy · #8 02-29-2016, 05:14 PM

Quote:

Originally Posted by braxtonds

Are you suggesting that the lights are too bright or dim? I have 3x 30W White and 1x 30W Red evenly spaced over an 8ft long table around 4 feet above the tables. How can I tell the strength of the lights?

Light meter. Also check specific bulb output spec sheets.

If you could post pics showing stages of leaf deterioration it may help to see what's going on.

silken · #9 02-29-2016, 06:21 PM

What type of heat do you use for your home? Did the worms move downstairs too or were they always there?

Ermie · #10 02-29-2016, 09:57 PM

Pictures could be appreciated. Although in Masdevallias, the two problems that plague most growers are humidity and temperature or, often, a combination of the two. For many members of the pleurothallid alliance, sudden humidity drops too minute for us humans to feel will often lead to signs of dehydration and overheating in the plant.

Another commonly encountered problem with this alliance is disease, especially when kept in the house or outdoors when outdoor growing in the US is a viable option for this genus. Extremely fragile, Masdevallias can fall prone to diseases especially easily. Also, due to the increased fragility of their leaves, you need to be quick in diagnosing the sickness as leaves will drop extremely rapidly.

Once again, pictures are your most sure way to get it rapidly diagnosed online.