Skip Navigation

University of Nebraska–Lincoln

UNL Gardens

A Beautiful Way To Learn

Articles

Weather or Not
September in the Perennial Garden

Weather or Not



One of the most significant challenges facing any gardener in Lincoln is the weather. Situated mid-continent, we suffer (or enjoy, depending on your preference) extremes in temperature unknown in areas with the moderating influences of nearby oceans. It’s not only seasonal extremes that gardeners must contend with (Lincoln’s record winter low of -33 and summer high of 115), but any given day of the year can easily range 10, 20, even 30 degrees from the daily average. And any of those days can see the temperature rocket or plummet 40 or better from sunrise to late afternoon.

Most of us understand the folly of TV weathercasters when they tell us the “normal” temperature for the day. We know that it’s perfectly “normal” for July 15th to be 100, but it could just as easily be 70.  April 15th could also reach 70 but, then again, 40. The same could be said of October 15th. January 15th is often below zero, but it could be one of those welcome “January thaw” days when it over  70, sunny with a warm Chinook wind. We are a place of temperature extremes; we probably break records at having record-breaking days. Bluebird Nurseries slogan, “If they’ll grow in Nebraska, they’ll grow anywhere!” is no idle sales pitch.

Personally, I love it. I love the seasons here and the changes of seasons, whether it’s spring into summer abruptly in a week’s time, or a lingering warm fall that won’t give way to winter without a fight. I wouldn’t want to live in a place where high summer lasts barely a good month, nor—though I’m hardly a fan of winter—would I want to live where roses bloom year-round. Give me Nebraska extremes; let me feel the seasons as a gardener, with cyclical rebirth, growth, and death.

In addition to temperature extremes, we deal with tornadoes, blizzards, hail, relentless desiccating winds, flooding and, as the past year has made abundantly clear, we cope with drought.

Precipitation in Lincoln is another area of climatilogical extremes. On average, we receive about twenty-eight inches per year—about the same as London, although seem to get theirs as endless year-round drizzle, while ours often comes as a few crash and boom thunderstorms. But precipitation too varies from year to year: in 1965 we got over forty-five inches, in 1936 a scant fourteen. And fourteen inches was the total for the single month of August in 1910—a minor miracle in itself. In December of 1973, 19.9 inches of snow fell in Lincoln; not many recent years accumulated that much in an entire season. I remember a summer in the early 90s when, contrary to what actual records may show, it felt like every afternoon for weeks the sky opened and deluged us with an inch of rain. We all know about the springs when you can’t stand to wait any longer and finally give up on there ever being a dry day and you plant your annuals in the mud during a cold, fine drizzle. And then there’s those autumns when the leaves that you crunched and kicked through in the gutter on your way to school as a child feel more like soggy cornflakes all season.

Finally, every once in a while, we get a year like this past one: a painfully dry fall moving into a snowless 40 winter, no rain to speak of in the spring, then a parched summer giving way to another dry fall. The few rains we did have—a quarter inch here, a half inch there—didn’t even make it through a decent layer of mulch. Hands shading our eyes, we turn our faces skyward and search for signs of rain. The only clouds we find stream north (lucky Omaha, we think), or south, or skirt us to the east. It can make a gardener a little crazy.

Without the welcome respite of a thunderstorm, we begin to fantasize:
There’s been an endless run of hot and humid days, we’re out in the garden doing what we do, but by late morning we sense a change in the air, a different density or smell. We think, “Something’s up.” Sometime after lunch, the oppressive humidity reaches saturation point and the wind, which has been blowing relentlessly for days, stops. It is completely still, the air drips, the lawns steam; birds rush about on important business—they know. Then you see them building in the west, thunderheads piling higher and higher. Finally, the pressure and humidity and heat reach a breaking point; the gust front blows through 80, feels like a cool spring breeze. The first few heavy drops of rain plop and splatter on the baked concrete—you swear you can hear the hiss. The smell of rain overwhelms you and, as you run for cover, you glance upwards toward the heavens and a thankful smile spreads across your face. The storm blows through quick enough that you get a spectacular rainbow while barbecuing dinner that evening.

In lieu of fantasy, what can gardeners do when confronted by drought? We take seriously the lesson of putting the appropriate plant in the appropriate place, we gravitate to more natives, those tough prairie plants that seem to thrive during years like this, we follow watering recommendations, and when we realize we can’t keep up with the watering on everything, we choose some things for sacrifice. If they make it, fine; if not, we figure out a better replacement for next time. We don’t get fooled into complacency by a shower or two, and we send our trees and shrubs to be in the fall deeply soaked. We install drip irrigation, read about drought tolerant plants, practice, xeriscaping. We mulch. And, as gardeners, we know there’s always next year.

Emily Levine

Originally published in The Garden News, November 2000

 


   
September in the Perennial Garden                                                                                                
The middle of September. That strange in-between time. The end of summer, but fall not really here yet. The weather’s all over the place: it could be 45, it could be 85.  And the garden? It can have that exhausted end of the season look with plants struggling to put out a few more blooms with the last of their energy.  But, if you plan it right, your herbaceous beds can look vibrant and fresh as spring. You just have to know what to plant.

Late season bloomers are taking center stage at Maxwell Arboretum’s Yeutter Garden and Fleming Slope. Japanese Anemone (Anemone ×hybrida) is a species that deserves more attention. It prefers part sun, but will tolerate shade so it’s a good substitute for the tired impatiens/hosta shade bed. It will also give you some nice height in the late season garden. The cultivar at Yeutter is ‘Whirlwind,’ a pure white semi-double that blooms from mid September to mid October.

Plumbago (Ceratostigma plumbaginoides) can’t be beat for tolerating a wide range of conditions. It blooms August through October in full sun along a south-facing street curb with no supplemental irrigation, as well as at the bottom of Fleming Slope—a moist environment with full shade in the afternoon. As fall progresses, its foliage turns a deep red.

Plumbago’s late season blue blooms are complimented by Blue Mist Spirea (Caryopteris ×cladonensis, not a true spirea), a “sub shrub” that flowers from late summer into fall. Turtlehead (Chelone lyonii) is another underutilized September bloomer. Its deep green foliage creates a wonderful backdrop for the distinctive pink blossoms that give the plant its name. On Yeutter Berm you can find the straight species as well as the cultivar ‘Hot Lips.’

These are just four examples of the myriad of late season bloomers that await you at Maxwell Arboretum—and await your green thumbs so that you can try them in your own yards.  Here’s a list of other herbaceous plants and sub shrubs to look for when you visit Maxwell Arboretum this September:

Gaura lindheimeri    White Gaura
Heliopsis helianthoides ‘Summer Sun’  False Sunflower
Helenium autumnale    ‘Rotgold’ and the species   Sneezeweed
Solidago    ‘Crown of Rays’ and ‘Golden Baby’   Goldenrod
Lagerstroemia  Fleming Filligrees ‘Coral Filli’ ‘Red Filli’ ‘Violet Filli’  Hardy Crapemyrtle
Aster novae-angliae    ‘Purple Dome’ and ‘Alma Potsche’
Dendranthemum ×grandiflorum  ‘Clara Curtis’   Chrysanthemum
Sedum   ‘Autumn Joy’   Sedum
Boltonia asteroides   ‘Snowbank’   Boltonia

Remember to stop deadheading many of your perennials at this time to insure winter interest seedheads. In addition to providing beautiful seedheads, planting grasses, especially natives, will add great color, texture, and movement to your late season garden.