Record-breaking temperatures, sudden and dramatic shifts in the weather, natural disasters. It’s been a wild year, weather-wise. And it may be just the beginning.
Our low temperatures during winter have been getting less low – in fact, the lows are rising faster than the overall average temperature. For Nebraskans who grew up with freezing cold, snow and blizzards, it sounds great!
Or does it?
Those miserably cold winters have provided dependable pest control, limiting insect pests for months at a time. What if temperatures remain too high to control our insect pests? And, even worse, might “foreign” pests from southern climates move into our area and wreak additional havoc on plants?
Invasive plants might also take advantage of an altered climate and compete more aggressively with native species. (Weeds did exceptionally well this past summer; perhaps you noticed.)
Besides higher low temperatures in winter, another aspect of the changing climate is increasing weather extremes. Droughts may last longer and, when it does rain, the rainfall could be much heavier.
Erratic weather patterns could increase shifting of the polar vortex, like the southward shift of the north polar vortex that occurred in 2014. The results of that weather event were devastating because of the steep temperature drop before plants had finished the cold hardening process; water remaining in plant cells froze, causing expansion and a rupture of delicate cell membranes. Hardest hit were willow and red maple trees. Magnolia and cherry trees, as well as many deciduous shrubs, suffered or died that year.
An added challenge of a “warming” winter is that fruit trees may break bud much earlier. If that happens, and there is a spring frost, it will affect fruit production. This was our experience in 2016 with our apple trees. This year, thankfully, the weather cooperated and we spent the fall months harvesting, cooking, giving away and eating our bountiful supply of apples.
So, what does a gardener do? Start planting trees suitable for Zone 8? Not yet. Remember that part about weather extremes? It will still get cold, just less reliably.
The best bet is plant diversity. The more diverse the plant material, the more likelihood of success. Consider adding plants that can endure hotter and colder temperatures and adjust to drought conditions that mix with significant wet periods. The Nebraska Statewide Arboretum has lists of plants that are water-wise, diverse and pollinator-friendly. Its website is plantnebraska.org.
Mulching will also help. Adding mulch around trees and in garden areas conserves moisture during drought, reduces soil temperatures in the heat of summer and provides an insulating layer.
Think about reducing turf areas and increasing native trees, shrubs and wildflowers. Doing so will help pollinators and reduce adverse environmental impacts such as fertilizer use. And you would have less mowing to do, allowing you to enjoy whatever the weather might be.