Our main goal is to encourage positive root growth. The combination of cooler temperatures and fall rain allows solid root establishment, making it easier for them to adjust to extreme heat or drought in the summer. Although you may fear a young tree or shrub cannot withstand the winter, as shoot growth halts, the rate of photosynthesis decreases and less water is needed. Soils also stay warm well after the air temperature cools and continue to encourage root growth while shoots stay dormant.
It is important to choose the right trees and shrubs for your location and needs. Certain plants have specific requirements, such as soil type, light requirements or water demands. Understanding what planting zone you live in helps you select the best trees and shrubs to plant and helps you become aware of how timing could affect whether your plants survive the winter months. When choosing a specimen from your favorite local nursery like Hahamongna or Artemesia, you want to be aware of any structural root flaws that may be initially present as they are not self correcting and will become more severe over time. The best nurseries will be highly considerate of this while choosing container size and they will be happy to answer any of your questions on site.
In the article Take it ALL off! Maximizing Planting Success of Trees and Shrubs by Linda Chalker Scott, she emphasizes the importance of removing all planting media whether soilless mix or clay and keeping the roots in a shaded, cool, moist environment while you work. This can be time consuming, however, it is the most crucial step to ensure a healthy and structurally sound root system. If needed, the root system can even be submerged in water for several days without harming the plant.
Once you are ready to plant, the planting hole itself should mimic the shape of the plant’s root system – not the shape of the container – and soil should be backfilled unamended. Unlike a vegetable garden or agricultural field, landscape soils cannot be amended on a yearly basis or the added organic materials can destroy soil structure as well as the roots we are trying to encourage. Using mulch or top-dressing are better options to protect root and soil integrity while also protecting against cold winter temperatures.
As you gaze at your newly planted contribution to the planet one last time make sure the root crown is visible and not buried below the soil’s surface. A buried crown can lead to a lack of adequate oxygen, slowed nutrient uptake and susceptibility to disease. Lastly, don’t forget to water during the first year! All transplants, whether they are drought tolerant or not, require frequent irrigation until roots are established.