Best bet for drought conditions: Water plants, soak trees and let grass go dormant, experts say

Rain could be a welcome sight this weekend for property owners trying to keep their grass, plants and trees green.

The last time the Naperville area saw any significant rain was May 12 when the National Weather Service station in Romeoville recorded .63 inches of precipitation, meteorologist Casey Sullivan said.

Records show precipitation is down more than 4 inches this year from an average of 16.94 inches, he said.

Nearly all the Chicago metropolitan area — including DuPage and Will counties — is in a moderate drought, according to U.S. Drought Monitor information released Thursday. A moderate drought is characterized by some crop damage; low water levels in streams, reservoirs or wells; and a high risk of fire.

Some relief from the dry conditions could arrive in the coming days.

The forecast from the National Weather Service shows a chance of showers from Saturday night through Tuesday.

But it’s unlikely to make up for the 4-inch deficit.

Naperville lawns, plants and trees already are showing signs of distress, according to certified arborist Ron Johnson of Naperville-based Steve Piper & Sons Tree Service.

Johnson suggests watering grass, flowers and vegetables when the soil gets dry or when watering is permitted.

Naperville allows sprinkling from 6 to 10 a.m. and 6 to 10 p.m. on even days of the month for people residing at even-numbered addresses or odd days for odd-numbered addresses.

It’s best to water in the morning or afternoon to allow time for leaves and soil to dry out, Johnson said.

Watering late means the leaves and roots will be wet all night when it’s cooler, and that promotes fungus, Johnson said.

Trees, particularly young ones planted in the past few years, need an inch of water a week, he said, and a sign a tree might be in distress is when the leaves start to droop.

It’s a misconception that sprinkling systems provide enough water for trees, Johnson said.

“Because you’re watering in the morning and you’re only watering for a short period of time, most of that water doesn’t even get down to the root system. It goes down a couple inches, and then it evaporates in the heat of the day,” he said.

A tree’s root system is deeper than grass roots so owners will want to give trees additional water in a slow trickle.

“You can water all the way up to when the ground freezes,” Johnson said.

Another problem homeowners need to watch this season is for insects, he said.

Because this past winter was mild and didn’t get cold enough to kill anything that was in the egg stages, the bug population is booming.

“The aphids are bad right now,” Johnson said.

“If you see your leaves start to curl up, that means it’s got aphids. You’ll see little black insects on the undersides of leaves. What they do is they inject their beak into the leaf tissue and then they suck out the juices in the leaves,” he said.

The University of Illinois Extension advises people with small gardens to wipe aphids from plants or blast them with a hose. A spray of water-soap solution also will kill the aphids without affecting predators or pollinators.

Johnson, who works with the city of Naperville and Naperville Park District, said park staff has reported seeing cutworms — moth larvae that feed after dark — on different plants.

Instead of watering lawns during a drought, people can choose to let their grass go dormant, said Cathy Clarkin, co-chair of the Naperville Environmental Sustainability Task force, or NEST.

“I think the word can get out that your grass can survive quite a while without being watered,” Clarkin said.

Selecting plants native to Illinois that have deep roots that can tolerate drought can help cut the need for watering, she added.

While Naperville has an abundant source of water with Lake Michigan, pumping and treating it takes energy so there’s an environmental impact when using a lot of water, Clarkin said.

Drought conditions may not last all summer.

State climatologist Trent Ford said Illinois is expected to see an overall increase in precipitation, although there also will be a change in the distribution and seasonality of the precipitation.

The state will see a rise in both heavy rainstorms and the length of dry spells, similar to what happened in 2021, Ford said.

“Everything was fine, and then we went into drought in April and May,” he said. “Things got kind of bad, but then the drought went away largely by the fall.”

That year also was punctuated by a June tornado in Naperville.

Will 2023 be like 2021?

“Now it’d be tough to say what’s going to happen with this drought,” or whether it’s a signal of more precipitation variability, Ford said.

In addition to more rain, air temperatures in Illinois are expected to continue to rise, which Ford said contributes to severity and intensity of naturally occurring droughts. That’s because water in the soil evaporates more quickly at higher temperatures.

The outlook for higher precipitation is problematic for municipalities like Naperville, said Clarkin, who also is co-chair and founder of nonprofit Accelerate Climate Solutions.

Communities use stormwater modeling to plan for infrastructure like the size of basins or drainage, Clarkin said.

If civic leaders are using outdated models, she said, they are less likely to be prepared for the anticipated heavy downpours or large-scale flooding.

“What needs to happen is to update stormwater modeling so it reflects this new reality of climate change, and that hasn’t quite happened yet,” Clarkin said.

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