Hello Kathleen,

It sounds like your petunias may be dealing with a common pest infestation—possibly whiteflies, thrips, or spider mites, all of which can appear as tiny white or pale specks and are known to target petunias. Here's a breakdown of what might be happening and what you can do:

What Are These Tiny White Bugs?

Spider mites: Often appear as tiny white or reddish dots and create fine webbing. They thrive in hot, dry conditions and can rapidly multiply.

Whiteflies: Small, moth-like insects that flutter when disturbed. They feed on plant sap, leaving behind sticky residue.

Thrips: Slender, pale insects that scrape plant tissue and suck out juices, causing silvery or speckled damage.

Petunias are especially vulnerable to these pests due to their soft foliage and frequent placement in sunny, warm spots.

To control spider mites, whiteflies, and thrips on petunias in Michigan, consider the following methods:

Use Insecticidal Soaps: These are effective against soft-bodied insects like spider mites, whiteflies, and thrips.

Natural Predators: Introduce predatory mites to help manage spider mite populations naturally.

Integrated Pest Management (IPM): Implement a comprehensive approach that includes multiple control strategies to reduce pest populations and maintain plant health.

Monitor Conditions: Be aware of environmental conditions that may affect spider mite populations, such as drought and leaf surfaces.

By combining these strategies, you can effectively manage pests on your petunias.

More information at this link:

How to control invasive pests while protecting pollinators and other beneficial insects - Beekeeping & Pollinators

Why Just the Petunias?

Plant-specific attraction: Petunias emit scents and have leaf textures that attract certain pests more than impatiens.

Microclimate differences: Even a few feet apart, the petunias may be getting more sun or less airflow, creating ideal conditions for mites or whiteflies.

Impatiens resistance: Impatiens are less attractive to many common petunia pests and may have thicker leaves or natural deterrents.

Should You Toss the Baskets?

You can toss them if:

The infestation is severe and spreading.

You don’t want to risk it affecting nearby plants.

You’re not interested in treating the issue.

But if you’d like to try saving them:

Isolate the baskets immediately.

Spray with insecticidal soap or neem oil.

Rinse the foliage thoroughly with water to dislodge pests.

Repeat treatment every few days until pests are gone.

What Brought This On?

Weather: Warm, dry spells in Michigan can trigger spider mite outbreaks.

Overcrowding or poor airflow: Hanging baskets often have limited ventilation.

Lack of natural predators: Indoors or sheltered areas may lack ladybugs or lacewings that keep pests in check.

If you’re curious to ID the pest more precisely, you could submit a photo to the Plant & Pest Diagnostics Lab.

I recommend you send your image by email to the MSU Plant & Pest Diagnostics Lab to get a confirmed and precise diagnosis and identification.

Their email is <personal data hidden> - Please include your first and last name.

The experts there can also provide you with the best treatment options.

The lab will let you know if they need a sample sent.

The lab may also ask for additional images. So be prepared.

Their website is at this link:

Plant & Pest Diagnostics (msu.edu)

Their Contact Information is at this link:

Contact Us - Plant & Pest Diagnostics (msu.edu)

This link will explain the details on submitting a sample to the MSU Plant & Pest Diagnostics Lab:

Submit Samples - Plant & Pest Diagnostics (msu.edu)

I hope this helps!