Fall Weather Patterns Predict Early Freeze, Deepening Drought

By Kathleen Cue, Nebraska Extension Horticulture Educator

The National Weather Service’s Climate Prediction Center has some startling news for September 12 through the 15th—a cold front moving through the central Great Plains region will bring falling temperatures, with a moderate risk of these temperatures being below freezing. How far temperatures fall is dependent on just how cold the cold front is and how much water is in the air (the dew point.) Dry air fluctuates more readily from hot to cold temperatures than moist air does. This follows through with soils too, with cold temperatures extending deeper into drought stressed soils than wet ones.

Typically this region doesn’t see a damaging frost until around October 10. Fruits and warm season vegetables like tomatoes will be hit hard by freezing temperatures. Covering un-harvested crops traps warmth around plants and acts as a physical barrier to freezing temperatures. Several layers of plastic or bed sheets do better at trapping warmth than a single layer. Buckets can be inverted over tall plants with a brick or rock on top to keep the bucket from toppling. More information about the predicted freeze may be found here: https://www.cpc.ncep.noaa.gov/products/predictions/threats/threats.php .

With drought conditions deepening, getting out the garden hose and the watering can are crucial.  Plants native to the Midwest won’t necessarily need water now, unless they were newly-planted this year. (Well-established native trees, shrubs and wildflowers weather periods of wet and periods of dry.)

Watering Priorities

▪Anything newly planted this season requires attention now. New plants do not have the extensive root system as their well-established counterparts. Drip irrigation does dual duty by watering deeply while losing less water to evaporation. Innovative ways for your own DIY drip system include placing water-filled gallon milk jugs next to plants, with each jug having up to 3 tiny holes on the bottom to provide drip irrigation. For new trees and shrubs, a 5 gallon bucket, drilled with (3) 1/8-inch holes, can be placed over the rootball, then the buckets filled with water.

▪Established plants, like fruit trees, shrubs, trees, roses and perennials need about an inch of water per week. With August being one of the driest on record, deep watering is necessary to reach all of the plants’ roots.  Set the garden hose to trickle and leave it on for extended periods, moving the end of the hose multiple times beneath tree and shrub canopies to reach as many roots as possible.  Another option, an idea provided by Burt County’s John Wilson, is to duct tape a double layer of old socks over the end of the garden hose and turn the faucet on. Water won’t come out in a gush and cause erosion but instead bubbles out with enough aeration to soak in.

▪Lawns comprised of Kentucky bluegrass can be allowed to go dormant during dry periods, provided lawns are given ½ inch of water every third week to keep turf crowns hydrated. Turf type tall fescue avoids drought by developing an extensive root system to tap lower sources of soil water. Once fescue has utilized all of the water within its root zone, however, plants die, so providing 1 inch of water every month during drought is important to keep fescue alive.

For more on wise watering practices, check out this link:  https://water.unl.edu/category/lawns-gardens-landscapes/lawn-landscape-irrigation?mobile=no&page=1  .

Go to Dodge County Horticulture Web Page for mor gardeing information.

 Photo: Pears