4 Reasons Your Petunias Are Wilting—and What Pro Gardeners Say You Should Do Before It Gets Worse

Key Points

The most common reason for petunias wilting is underwatering.

Other frequent causes include fungal disease, pests, and overwatering.

Avoid watering petunias’ leaves and pinch off pest-infested blossoms and discolored leaves.

With their wide range of colors and long flowering season, it’s no wonder that petunias are a home garden staple. Wilting can affect petunia blossoms, particularly in the summertime.

Luckily, there are several easy, practical steps that you can take to avoid wilting and keep your petunias lush and thriving all year long. We asked gardening professionals for their best pointers.

Meet the Expert

Lorraine Ballato is an instructor at the New York Botanical Garden and the author of Success With Hydrangeas.

4 Reasons Why Your Petunias Are Wilting

Here are a few common reasons our experts said your petunias might be wilting.

Underwatering

Gardening expert Jen McDonald says that underwatering is the most common reason for petunias wilting.

“Petunias have shallow root systems and benefit from regular watering at the base of the plant,” she says. “In the summer, petunias may require a double dose of water to keep blooms looking perky.”

Fungal Disease

Fungal disease in petunias often results from overcrowding, humidity, or overwatering (or some combination of the three). If your petunias have discolored leaves, this could be a sign that they’re suffering from this condition.

“When fungal disease occurs, it cuts off [air] circulation from the stem,” McDonald says. “This results in suffocation and death.”

In order to prevent fungal disease, water your petunias at the base of each plant, rather than their leaves.

“Water in the morning so that the plant has time to absorb the nutrients and make sure that the plants are not overcrowded,” McDonald recommends. “Regularly pinch off any dead blooms and remove discolored leaves.”

Pests

Pests can exacerbate the issues that your wilting flowers may be experiencing.

“Aphids and spider mites in particular can be drawn to petunia sap,” McDonald says. “It’s important to inspect your petunias regularly, and if it looks like you have an invasion of unwanted guests, pinch the flowers off or blast them with a spray from [your] hose to remove [them].”

Lorraine Ballato, an instructor at the New York Botanical Garden, recommends inspecting the affected plant with a magnifying glass or hand lens to check for any other small piercing insects

“Treatment should occur when pollinators aren’t active and only with pollinator-friendly products like neem,” she adds.

Overwatering

If your petunias are wilting and their leaves are turning yellow, you’re likely overwatering them.

“Root rot occurs when the water doesn’t have a chance to drain, suffocating the plant from the roots to the leaves,” McDonald explains.

In order to prevent overwatering, she recommends conducting the “fingertip test.” Simply stick your finger 1-2 inches into the soil.

“It should feel damp, but not soggy,” McDonald says. “Once root rot sets in, the plant will not recover.”

5 Ways to Prevent Petunias from Wilting

Taking proactive steps to care for your plants can go a long way in preventing them from wilting. In order to avoid poor petunia plant health, try these tips:

Water petunias twice a day as needed during summer days.

Don’t water your petunias’ leaves.

Monitor your petunias for pests and pinch off affected blooms.

Conduct a “fingertip test” to avoid overwatering your petunias.

Remove discolored leaves to fend off fungal disease.

Read the original article on The Spruce