When you stop to think about it, trees & shrubs are the foundation or backdrop for everything else that we grow. They remain and slowly change over time by getting larger, creating shady habitats for other plants that will come & go over the years. On the other hand, forces beyond our control can make trees and shrubs change dramatically. Weakened branches can snap off in a storm...climate stress can pave the way for disease & insect problems...and all these problems can persist and get worse over time.
This year in our area (Northwestern Pennsylvania - zone 5) we saw it all - extremes of spring floods, a month-long drought in July, and record breaking rainfall in the months of September & October. All these events are stressful at the time, but easily forgotten a year or two down the road. Then a tree starts dying from the ground up, or a branch will go here or there...all a result of conditions we cannot control.
All is not lost. What we can do for those trees & shrubs that we hope survive well past our turn as "gardener in chief" are a couple of simple things that amount to "food & drink". The time of the year after leaves have dropped & before the ground freezes is short but is your chance to make a huge difference in the quality of your landscape long-term.
Woody ornamentals (i.e. trees & shrubs) will benefit greatly from a light application of a tree/shrub fertilizer (or even straight Nitrogen if that's all you have). Just spread a granular (or liquid spray) fertilizer evenly under the tree & out past the canopy if you can. Then let the snow or rain water it in. What I love about this time of year is that even the least expensive fast-release fertilizer won't burn.
You may be thinking "Fertilize in the Fall?? You're crazy!" - I know I did. I'd been taught that this would send a tree into winter in a weaker state making it more susceptible to the impending cold. Research done some time ago shows that tree/shrub roots (which are still actively growing in ground that is actually warmer than the air this time of year) will take up nutrients in the fall & store them until spring. Trees that are already hardened off will not break dormancy. As our "woodies" begin to grow & leaf out in the spring, these nutrients are gradually available. This avoids the problem of rapid/succulent growth that spring fertilizer applications can create.
Additionally, if you live where the ground freezes in winter, have a sandy soil that dries out quickly, or don't get plenty of rain just before winter, all "woodies" will benefit from a good drink of water. Just set a garden hose on low & let the water really soak in while you're planting tulips, a new tree just bought on sale, or digging dahlias for storage. Yes, you do need to move the hose occasionally, but anything you do now will pay dividends next year. Conversely, if the forecast is for plenty of rain, know that Mother Nature is taking care of it for you this year.
Once the ground is frozen, it's time to mulch. Normally, that's around Thanksgiving in our area. This means we still have a couple of weeks to give a healthy boost to those plants we want to nurture for years to come.
