Nebraska fall gets discussed in terms of the first freeze and the wind. Those matter, but neither is what actually ends a straw bale here.
What ends it is moisture that never gets a chance to leave.
Why humidity is different from rain
A bale can shed a downpour. Water hits the outside, runs off the sides, and the interior stays dry.
Sustained humidity works differently. There's no runoff, nothing dramatic to react to — just damp air holding moisture against and inside the bale for days at a time, with no dry stretch long enough to let it out. The bale takes on water gradually and never gives it back.
That's how a bale that looks fine in early October is dark and slumping by the end of the month without a single memorable storm.
Airflow is the whole answer
Anything that lets air move through and around the bale extends its life.
Raise itOn soil or grass, ground moisture wicks straight up. A pallet or a pair of pavers underneath creates a gap, and that gap does more than anything else on this list.
String side downSet the bale so it rests on a string side, with the strings running across the top. Cut side down puts the open stem ends against the ground, and cut stems wick moisture straight up into the bale.
Give it spaceA bale pressed flat against siding traps damp on the wall side. A few inches of gap lets that face breathe.
Keep it out of the low spotWherever water pools on your walkway after a storm, that's where a bale should never sit.
What to watch for
The progression is consistent and it starts at the bottom.
First the base darkens. Then the bale loses its crisp edges and the corners round off. Then the binding goes slack, because a bale that's taken on water swells and then settles. Then you get the smell, and after that, visible mold at the ground contact.
Catch it at the darkening stage and raising the bale can still help. Past the slack-binding stage it's finished.
Check under the pumpkins too
Humidity works on pumpkins the same way it works on straw, and the contact points are where it shows.
Anywhere a pumpkin touches the bale, the porch floor, or another pumpkin, moisture gets trapped. Lift a few pieces every couple of weeks and look at the undersides. A soft, darkened patch is the signal to pull that piece before it takes its neighbors.
Covered porches win here
If you have a choice between a spot that looks slightly better and a spot with a roof over it, take the roof.
A covered Midwestern porch is a genuinely good environment for a fall display. An exposed stoop with no overhang is the hard version, and it's worth planning around — raise everything, leave gaps, and check it more often.