Even though Oklahoma continues to experience summer temperatures, homeowners who want to get new trees or shrubs planted should start making plans to do so now. Fall not only is a great time for decorating with pumpkins and scarecrows, it’s also a good time to get new trees and shrubs planted before winter hits.
Planting trees and shrubs in the fall gives the root system an opportunity to grow and become established before the winter cold hits. Roots grow best when the soil temperature is above 40 degrees. Giving the root system a chance to become established will help them survive the winter. When warmer weather arrives in the spring, these established root systems can better support and take advantage of the growth surge that occurs during that time of year.
It’s important to get new trees and shrubs in the ground soon. Everyone remembers the ice storm Oklahoma experienced in October 2020. Waiting too long to get trees and shrubs planted won’t give them enough time to establish a healthy root system in the event Mother Nature throws another epic storm this way earlier than Oklahoma typically experiences extreme weather conditions.
When choosing trees or shrubs, select balled and burlap or container-grown options for planting now. Hold off until late winter to plant bare-plants because they need to be dormant when going into the ground. Broadleaf evergreens are best planted in the spring too.
Proper planting is a must for success. Dig a hole at least two times wider than the root ball. The hole shouldn’t be any deeper than the root ball. In heavy, poorly drained soils, plant the tree or shrub so the top of the root ball is just above the level of the surrounding soil. This allows for settling and increases soil drainage and available oxygen to the roots.
Fill the hole using only the soil that was removed when digging and pat it down around the plant. Water thoroughly to settle the soil and eliminate air pockets. A thorough watering every seven to 10 days increases planting success. Overwatering may encourage root rot. Typically, trees and shrubs fail due to overwatering as opposed to underwatering.
As tempting as it may be, hold off on fertilizing a tree or shrub after planting. Spring is a better time to apply fertilizer. A heavy application of fertilizer at planting can burn or injure the root system, which could result in the tree or shrub dying; a late application of high amounts of nitrogen may lead to a late flush of new growth that will not acclimate in time for cold weather and will likely result in damage.
Mulch is a great addition to newly planted trees and shrubs to help conserve water, as well as cut down on weed growth.
Trees and shrubs can be a significant investment, but an established landscape can certainly add value to any property. Check with your local garden stores and nurseries to see what varieties they have to offer.
Oklahoma State University Extension offers more advice in its Tree Planting Guide.
David Hillock is a consumer horticulturist with OSU cooperative extension.