Miltoniopsis Leaves Yellowing - Orchid Board

Gil · #1 08-11-2018, 06:31 PM

I have had this Milt. Arnold Linsman "Hot & Spicy" about 2 months. Half of the buds were opened and the rest opened fine.
I give it a drink with CalMax once a week and let the water drain through the roots well. I fertilize at the same time with 1/2 the prescribed amount. I have also used KelpMax and Inocucor on it.
It sits on a SE facing lightly tinted window sill and gets leaf shaded broken sunshine in the morning.
About a month ago one of the small flanking side leaves from the large psudobulb turned yellow and fell off. Two weeks later the small leaf on the opposite side did the same. Now two weeks later one of the larger leaves is starting to yellow.
I just wonder if perhaps the plant is not getting enough light, lacks some mineral or is getting too much water. I plan on a re-pot after the blooms go. It is in sphagnum and stays pretty moist all week.
The plant came from a local orchid shop. I have to give it calcium because our water is lacking it.
Help would be appreciated. We really like the pansey blooms.

Ray · #2 08-12-2018, 07:52 AM

Such leaf loss may not be an issue, as these tend to do that periodically, exposing the pseudobulbs while retaining the uppermost leaves only, but it could also be from cultural issues.

Has it been particularly hot there lately?

Could "pretty moist" mean "soppy in the middle"?

Your description of your fertilizer and additive regimen is entirely devoid of useful information to make a judgement about any impact that might have.

Gil · #3 08-12-2018, 08:50 AM

The orchid is located indoors since it is blooming and we want to enjoy the flowers. The highest daytime temperature it gets is 75 degrees.
The fertilizer is Dyna Grow Bloom 3-12-6 applied at 1/4 tsp every week. Normal is 1 tsp.
The KelpMax and Inocucor have only been applied once per instructions.

Checked the moss around it this morning and even tho it has been 6 days since last watering it is wet but not what I would call sopping wet. Probably will allow a few more days till I water it again and give it some outdoor time to help it dry.