Summer 2021 is one for the record books. Abnormally high temps have taken their toll on ecosystem functions, our environment and our landscapes.
As horticulturists and environmental professionals, we know that nature has an incredible ability to recover. Most plants damaged by heat will return with vigor when temperatures cool. Some will not.
Why is that?
Oregon landscapes, in general, don’t do well in heat more common to southwestern states. In fact, most of the plants acclimatized to our region show signs of stress when temperatures reach 85F. If a plant is under stress for too long, it can damage the plant’s photosynthesis system, which can cause irreversible damage and molecular changes. Left unchecked, heat stress can cause plants to dry up and die.
Some plants are more heat tolerant than others. Many factors – including duration of exposure, hardiness factors, heat index, and a plant’s ability to adapt and acclimate, can determine how well it will survive.
So, is this summer’s heat event an outlier or a trend and what can we do about it?
For decades, we’ve known that a growing body of research supports the same best practices we, too, believe in: that solutions are rooted in a respect for nature. That biodiversity strengthens ecosystems and landscapes, and improves the plants and the soil’s capacity to become more resilient and regenerative. Building and maintaining stronger, healthier landscape systems that work with nature will always be the best way to be strategic about the unexpected and ensure better recovery.
What does this mean in the short term if your landscape is struggling?
Our DeSantis heat response team suggests the following to help your landscape bounce back:
- Evaluate heat stress indicators: wilting leaves, drying and browning leaves and needles, leaf drop, branch dieback, sunburn on branches and trunks, reduced or no new growth, and overly dry soil.
- Conserve water by irrigating plants more efficiently and reducing the amount of water lost to evaporation.
- Adjust controlled irrigation to run early to give roots time to absorb moisture, and help prevent heat stress in foliage.
- Add mulch to provide a layer of protection, preserve hydration, and keep soil and root zone temperatures cool.
- Improve soil fertility with micronutrients to increase heat tolerance and soil health.
- Move smaller plants in containers to shaded areas.
- Assess plant response and heat tolerance, potential damage and course of action before pruning.
DeSantis Landscapes is your go-to for sunburn and heat impact assessments, determining next steps, and evaluating what extra measures and treatment options your plants and landscape might need. Learn more at www.desantislandscapes.com
Let’s keep the conversation going.