Brown markings - anyone know what these are?

[flowerpower]

I was watering my miltoniopsis and saw these brown specks on the leaves. I think they have become more prominent in the last week or two.
Does anyone know what they are and why they have formed? I love my miltoniopsis and want it to flourish.

Sorry about the picture quality

[King_of_orchid_growing:)]

How much are you fertilizing and are you using tap water?

[flowerpower]

Yes I am using tap water. I water when the soil is on the moist side. It is a new acquisition so I have only fertilised it once so far, with 50% strength orchid feed (5-6-7). I am not sure of its history re: fertiliser but it was bought from a supermarket.

[King_of_orchid_growing:)]

May I suggest using distilled water, RO/DI, or rainwater insteaad.

These guys don't like high dissolved minerals in the water.

Chlorine can also do damage to the plant.

They're very prone to leaf tip die back and leaf spotting.

[Izzie]

King- can orchids get fluoride poisoning light other houseplants?
I've always used filtered water (brita) just in case, but was curious.

Flowerpower- filter pitchers are pretty cheap at almost any big box store. Great investment!

[Duane McDowell]

Miltoniopsis frequently have these spots. Tap water can do it, overfertilizing can do it, letting them dry out can do it - I'll swear that looking at them sideways can make it happen. Good news is that it doesn't seem to affect their growth or blooming when it's a mild case like yours. I am a big believer in water with as little salt as possible. When I fertilize, I water the plants thoroughly first, and then fertilize. The plants should never dry out entirely.

[Izzie]

Originally Posted by Duane McDowell

Miltoniopsis frequently have these spots.- I'll swear that looking at them sideways can make it happen.

True that! I swear, some of these 'chids have us wrapped around their little.............rhizomes?

[flowerpower]

Originally Posted by Duane McDowell

Miltoniopsis frequently have these spots. Tap water can do it, overfertilizing can do it, letting them dry out can do it - I'll swear that looking at them sideways can make it happen. Good news is that it doesn't seem to affect their growth or blooming when it's a mild case like yours. I am a big believer in water with as little salt as possible. When I fertilize, I water the plants thoroughly first, and then fertilize. The plants should never dry out entirely.

Sounds like it could be dissolved particles in the water then. I will try not fertilising for a bit and continue keeping them moist.

I live in inner London, and seem to have very hard water. I can barely even drink it - which is luckily why I purchased a water filter ages ago. When I water it tomorrow I will use that and cross my fingers that it does not get worse because it looks so beautiful

[King_of_orchid_growing:)]

Originally Posted by Izzie

King- can orchids get fluoride poisoning light other houseplants?
I've always used filtered water (brita) just in case, but was curious.

I'm not particularly sure about this. But it's very possible.

A few days ago, I accidentally watered a newly acquired orchid with tap water and it didn't like it at all!

Almost immediately (after about a day) the sheath covering the new shoot turned brown. Luckily nothing serious happened to the plant.

Another individual of the same species of orchid didn't turn brown because I watered with filtered water.

Just a warning about how sensitive certain plants can be to tap water. It probably serves as a warning for people to stop drinking tap water too!

One other thing worth mentioning is that some orchids, particularly those collectively known as Pleurothallids, in general are notoriously sensitive to being watered with tap water.

Some species of Pleurothallid can die very rapidly (within a week or two) from being watered with tap water.