What Is Agave Root Rot and How To Treat Root Rot in Agave?

Agave root rot is when the agave plant’s roots deteriorate due to too little sun or too much moisture. 

The best way to treat root rot in Agave is by digging it up, removing the rotted roots, and treating it with a fungicide.

treating root rot on Agave plantsPin

Why is Agave Susceptible to Root Rot?

Agave plants are native to desert climates in North America. It’s famed for producing the alcoholic mezcal drink in Mexico, and it’s a natural sweetener for healthy food eaters. 

Agave thrives on rocky slopes where water doesn’t pool. It requires climates that experience infrequent rain, which is why it’s so susceptible to root rot.

Learn more on Agave Plant Care

Water Devastation

There are various species of Agave, with the prized Agave victoria-reginae being among the slowest to grow. It takes twenty years or more to flower, and it’s among the most prized Agave plants on the market.

For this reason, Agave root rot is especially devastating to Agave victoria-reginae growers – twenty years is a long time to pray for the rain to stay away.

Queen Victoria Century Plant growing in landscapePin
Agave victoria-reginae

Causes of Agave Root Rot

You already know that exposure to too much water causes Agave root rot, but unfortunately, this isn’t the only issue that can cause it. Below are other ways root rot can occur in Agave:

  • Agave growing in too much partial shade or shady conditions
  • Humid environment
  • Prolonged time in damp or soggy soil
  • Fungal and bacterial diseases
  • Insects chewing the plant
  • Extreme weather fluctuations between hot and cold weather

When Agave plant tissues become damaged from poor weather conditions, it opens up the opportunity for fungus and bacteria to enter the plant. In particular, the Fusarium fungus and Colletotriachum bacteria wreak havoc on Agave.  

Once the air heats up—and especially if there’s humidity—the fungus and bacteria spread quickly. The issue for farmers is that it’s difficult for them to identify when the roots are affected.

For this reason, Agave root rot can have a devastating impact on crops before anyone detects it. Often, homeowners discover their plant had root rot after it already tipped over from the entire root ball being too rotted to hold the plant upright.

Agave Snout Weevil

Agave root rot is a general term to describe rotted Agave roots, regardless of the cause. The Agave Snout Weevil is yet another threat to this desert plant.

Agave Snout Weevils dine on the lowest parts of Agave as an adult, transferring bacteria into the plant as it moves. The bacteria break down the Agave’s fibers, where the weevil then lays its eggs.

Once the weevil larvae hatch, they nourish themselves by eating the Agave’s rotting crown and roots.

Symptoms of Agave Root Rot

Are you suspicious that your Agave plant has root rot? Below are some tell-tale signs to look for.

  • Lesions around the plant crown
  • Tipped over plants
  • Unhealthy appearance on the leaves
  • Slimy roots that have a black or grey hue

Although root rot isn’t the only disease that occurs in Agave, it’s one of the most common. Therefore, it’s relatively easy to diagnose this issue.

How to Treat Root Rot On Agave Plants

If your Agave plant has root rot, not all hope is lost. By following these steps, you might be able to revive it.

  • Dig up the plant and shake the soil off its roots.
  • Trim all the rotting parts.
  • Use a copper fungicide or neem oil to treat the remaining roots.

    Read: Treating Root Rot with Neem Oil
  • Replant your Agave in a dryer, sunnier environment.
  • If your plant has poor drainage or isn’t ideal where you plant, mix pumice in with fresh soil.
  • Cross your fingers and hope for the best!

You might be wondering: what happens if you pull up your Agave and encounter completely rotted roots?

Unfortunately, there’s no way to save the plant.

However, you should make sure all the rotted roots are out of the soil and then treat the area with a copper fungicide. Otherwise, the fungus could spread to other Agave plants.

As a final word of warning, you shouldn’t take Agave “pups” from a plant with root rot and transplant them. Chances are they already have the root rot fungus or bacteria. 

How Much Water Does Agave Need?

You know that Agave doesn’t need much water, but it does require some here and there.

Assuming you’re not at the mercy of Mother Nature with large Agave plants, aim to water Agave once a month.

That said, if it rained during that month, skip watering.

Preventing Root Rot

Prevention is the best way to manage Agave root rot. If you’ve planted your Agave in a shady or wet area, consider digging it up before it shows signs of disease. 

Agaves need a well-draining soil. If you don’t have good drainage, you can build a rock bed to plant your Agave in or keep it as a potted plant. 

Overall, Agave is a sturdy plant; you can dig it up, chop up its roots, and replant it. 

By implementing the tips we discussed here, you’ll be on your way to treating your Agave root rot problem and preventing the issue from happening again.

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