What’s Up With This Weather?
We have been experiencing above average temperatures for the season. These warm temperatures are largely a result of the La Nina weather patterns that we discussed early this winter. We have to be prepared for the fact that we will likely experience more frosts or even freezing weather this spring, so what impact will these warm temperatures have on our plants moving forward?
First, some trees and shrubs are blooming early. For instance, the pear trees in my yard have already bloomed and started to leaf out. If we have freezing temperatures, these plants will be damaged by the cold. These early blooms are not likely to succeed in producing fruit. That means that I will have reduced fruit set and possibly no fruit set this year depending on the amount of bloom buds that open now and the plant in question (some plants have secondary and tertiary fruiting buds providing more backup).
As far as flowering plants are concerned (such as azaleas), only a small percentage of the flowers buds open during these early displays so while your spring bloom may be reduced, it should not be eliminated. Early leaves may be lost to freezing weather but spring and summer growth should compensate for the loss on healthy plants.
Fluctuating temperatures can also contribute to bark splitting. As temperatures cool from the heat of the day to the cold of night, tissues expand and contract and can cause damage. While we cannot control the weather, there are some steps that you can take to help protect your plants from fluctuating temperatures. Apply mulch to the root zone of trees and shrubs – no more than 4 inches deep and pulled away from the trunk. The mulch will not warm or cool the plants’ roots but it will help maintain steady soil temperature and reduce fluctuations. Wait until after the last frost to prune off cold damaged wood and wait until late June or early July to determine if a plant has been lost altogether. Some cold-damaged plants will push out new growth later in the season or send up new shoots from the roots. Finally, remember not to fertilize plants with nitrogen after midsummer. Nitrogen promotes soft, succulent growth that is more susceptible to cold damage. You want to give your plants plenty of time to harden off before winter.