Question: This has been a year of extreme weather events from January with temperatures in the 60s, a late February snowstorm, a March freeze with temps in the teens, an April frost, 90 degrees in May and a few summer thunderstorms with hail. It seems odd to say this, but my vegetable garden and apple and pear trees look pretty good. How is this possible?
Answer: What you describe is a wild weather year in Douglas County, but the impact of this type of season can be very damaging to some plants or locations and leave others untouched.
Since I cover a lot of ground looking at farm fields and talking with Master Gardeners on the job with OSU Extension, I would like to share a few thoughts on how to prepare your gardens for unpredictable weather that might help you in the years ahead.
This past winter started with some very mild and dry conditions that allowed the air temperature to climb into the 60s, which also kept the soil warmer than usual. To protect your fruit and flowering trees from budding out too early it is important to choose varieties that have a long chill requirement before they will break dormancy. This will keep them dormant until April in most years, missing nasty winter weather.
It will also help to plant your flowering or fruit trees where they do not have a southerly slope or exposure but instead on a northwest or north slope. This will keep the ground cooler and the trees dormant longer since the sunlight will not strike that soil directly in winter.
If your fruit or flowering trees are already established in your landscape on a southerly slope, you can mulch the soil around the trees to protect them from the harsh cold in winter, and the mulch will also keep the soil cooler in spring, slowing down bud break and early shoot growth. If winter arrives late like this past February and early March, your trees will most likely be dormant and not actively growing if they are on a northwestern or northerly slope.
The heavy snowfall we experienced this year in late February actually insulated the tree roots from a freeze but allowed the air temperature to go dramatically lower. This was devastating to early season flower buds on trees that had de-hardened and were coming out of dormancy. Choosing cold-hardy varieties of trees and shrubs can protect your future plantings.
In response to your question about why your fruit trees still looked good, I am guessing that your fruit trees must have still been dormant and not actively growing in February and March and that the April frost was pretty light in your area and caused no damage.
This is why growing tree fruit crops like apples and pears are more rewarding in our climate. Those species have a longer chill requirement and stay dormant longer than peaches, plums, cherries, and apricots, which typically blooms earlier, especially after a warm January.
Nature had an interesting way of compensating for a tough winter and spring season for those of us in Douglas County. It provided heavy rains in April to charge our soils for the growing season, and we warmed up quickly in May into the 90s, spurring new plant growth. That is why many of our damaged plants are doing their best to make new growth. That early warm weather also brought soil temperatures up into the 70s quickly and gave our vegetable gardens a great start.
Keep in mind that the winter weather is important for soil moisture recharge, but creating great soil is what makes a great vegetable garden. So our weird winter weather is mostly irrelevant to the success of your summer annuals, both food and flower crops.
Since May, the daytime high temperatures have been consistently in the 80s which is about perfect for both people and their gardens. We seem to be headed for the nicest summer weather since 2012.
By the way, in my opinion, that was the finest wine grape summer growing season in our area of the past 20 years. We may be headed for another amazing vintage.