Why is my Calathea sticky under the leaves?

Wondering why is my Calathea sticky under the leaves? Let's talk about the most common problem + solutions!

I have a beautiful peacock calathea that is super finicky and often unhappy.

Recently, I realized that the underside of all of the leaves was sticky with a thick sap.

Gross!

Let's talk about why this happened and how to fix it.

Read my Peacock Calathea indoor plant care guide!

Why is my Calathea sticky under the leaves?

There are 3 main causes of sticky calathea leaves:

1. Spider mite webbing
2. Honeydew from aphids, mealybugs, and scale insects
3. Sap secretions

Sticky leaves on a calathea are usually a sign of a pest infestation. Major bummer, I know.

Pests get onto the calathea plant leaves and suck out the sap. That makes the calathea leaves sticky.

This could also leave calathea crystals on leaves. These crystals could be crystalized sap and should be treated the same way.

Why is my Calathea sticky?

The main cause of sticky Calathea leaves is spider mites. They will feed on your leaves and leave sticky plants behind. This stickiness is usually caused by the webbing that the spider mites weave.

Aphids, mealybugs, and scales can also infect calathea plants and will lead to sticky leaves.

If your Calathea is sticky without any pests, it could just be secreting sap. This sweet sticky sap will attract ants, so you will want to clean the sticky off either way.

What is honeydew?

Honeydew is a secretion (yuck!) released by aphids, mealybugs, and scales on leaves. It's basically their poop. They suck sap out of leaves and poop out honeydew (HoneyDooDoo?)

If not cleaned, the honeydew creating sticky plant leaves will build up, drip, and can attract ant and other bugs.

How do you get rid of sticky residue on plants?

The best thing to do is determine the cause of your plant's sticky substance and treat it appropriately.

Regardless of the problem, you will want to wipe the sticky stuff off all of your plant leaves. Read my complete guide to cleaning plant leaves here!

If any leaves are VERY bad, you can always trim them off. Read my guide to trimming dead leaves here.

If you suspect pests, separate your plant from your other plants to help prevent spreading!

Spider Mites

Mix rubbing alcohol 1 part with 4 parts water. Wipe down the leaves.

Always isolate spider mite plants from other plants!

Aphids, mealybugs

Mealeybugs will be little white dots on your leaves.

Aphids and mealy bugs can be treated with neem oil on the leaves and stem. Then, wipe clean.

Scale

Scale will look like small oval brown lumps.

Scale needs to be removed by wiping down the leaves. Wet a soft cloth with warm water. For stubborn bugs, you can add rubbing alcohol or dish detergent/dish soap. Use a cotton swab or soft cloth.

Finally, you can try an insecticidal soap.

Sap secretions

If your plant is just sappy, wiping it with a warm wet cloth should clean it up! Repeat this twice to get off all the sticky.

To decrease guttation via sap secretions, never water your plant at night - excess water over night can lead to secretions.

Guttatation can also be caused by overwatering, so consider cutting back on your watering schedule!

Thanks for reading!