Climate change affects gardens and gardeners

Few phrases stir debate as furiously as global warming.

Dr. Sara Via, University of Maryland professor and climate-change specialist, recently shared the latest research findings and ways gardeners can adapt to climate change.

Global warming is real. Temperatures have been rising for decades, and the last three years have been the hottest ever globally. Carbon-dioxide levels also are on the upswing. It’s warm and getting warmer.

Why? The sun’s heat waves are redirected when they hit pollution-induced greenhouse-gas molecules in the atmosphere, bouncing around instead of going back into space.

Global warming is causing more extreme weather. Warmer air and oceans, plus more water vapor in the air and a higher sea levels, create conditions ripe for storms.

Our new normal is rising temperatures, which translate into warmer winters, earlier springs and more variable temperatures. This spring was a classic example.

Subtle changes can have dramatic effects. More frost-free winter days mean that plants such as fruit trees might not get the chilling period they need. Many fruits are blooming earlier, making them vulnerable to frost.

Temperature fluctuations can result in a false spring. A warm February could be followed by a freeze in March or April, devastating fruit crops in bloom. This happens periodically, but it’s happening more often.

Weeds love warm winters. They overwinter better, green up and flower earlier. Fight back by weeding early and often, mulching well or using cover crops. Avoid tilling, which exposes weed seeds.

Pests and diseases also are surviving our warmer winters better. They show up earlier, have more generations and range farther. Learn to detect early signs and aggressively control problems.

Summer heat stress is increasing. Pollen tubes don’t grow if it’s too hot. Tomatoes, peppers and others drop flowers. Corn kernels dry up. Plants that are not pollinated can’t produce food.

To avoid heat stress, plant earlier in the spring and later in the fall, using row covers to manage frost. Try heat-resistant varieties. Use existing shade or build shade covers.

Climate change is causing more downpours. Heavy rains delay planting, wash away seeds, cause erosion and keep the soil wet, encouraging pathogens.

Improve soil drainage by adding organic matter. Add deep-rooted native plants and a rain garden, both of which handle gully washers and limit erosion.

Droughts are increasing, too. Plan ahead by incorporating drought-tolerant plants and wise watering techniques, such as rain barrels and soaker hoses. Mulch beds or use ground covers.

Opt for cultural, not chemical, pest controls. Learn organic techniques and plant many types of flowering plants to attract beneficial insects that help control bad bugs.

Reduce your lawn. The U.S. has 42 million acres of lawns, our largest irrigated crop. Many lawns are overfertilized, causing polluting runoff. Use only the fertilizer your soil test recommends and allow your lawn to go dormant in the summer.

A total of 81 million Americans have properties. What you do as a gardener matters.

I hope these tips help you create climate-friendly gardens.