Gramm spieces prob

[Rluciano]

My gramm is developing black motteling and a sticky substance on the back of the older leaves. Otherwise plant is doing great
What’s the mottleing and what’s the sticky substance

[estación seca]

Welcome to the Orchid Board!

Where do you live? What are temperatures and humidity like? Is the plant inside or outside?

Some bugs like mealybugs, aphids and scale secrete sugary substances. In high humidity areas the sugar can grow black mold.

In extremely humid climates black mold can grow on the surfaces of leaves even without sugar.

Examine with a magnifying glass for the bugs I mentioned. Wash off the leaves with a mixture of 1 teaspoon / 5ml of liquid dish soap per quart / liter of water.