How to Plant an Oak (and Why You Should)
Photo by Rose Lane
By Maddie Mann, AmeriCorps Project Conserve Communications and Education Associate
Why Plant Oak Trees?
We need more oak trees! Oak trees are a keystone species, meaning they are the backbone of many forest communities and ecosystems depend on them for survival. Sadly, oak populations have been declining for some time now. Whether it be from disease, urban development, drought, or invasive pests, oak trees are need our help. This month’s Habitat at Home article runs hand-in-hand with our upcoming Gardening for Life Celebration! As the event’s keynote speaker, Doug Tallamy will be discussing his newest book, The Nature of Oaks: The Rich Ecology of Our Most Essential Native Trees. Throughout the book, Doug observes oak trees from his own backyard over the course of a year. He also includes his methods of growing oaks and his preferences for acorns or bareroot whips instead of potted trees. Consider this a step-by-step guide to planting your very own oak!
What Kind of Oaks Grow Best in Western NC?
In The Nature of Oaks, Doug Tallamy lists the best oaks for your area, and categorizes them by regions of the country and their relative sizes. Here are the trees he states would grow best in western North Carolina:
- Northern White Oak
- Southern Red Oak
- Shingle Oak*
- Laurel Oak
- Chestnut Oak
- Water Oak
- Cherry-Bark Oak
- Pin Oak*
- Willow Oak
- Northern Red Oak
- Shumard’s Oak
- Post Oak
- Black Oak
- Bluff Oak*
- Swamp White Oak*
- Scarlet Oak
- Georgia Oak*
- Overcup Oak
- Blackjack Oak
- Swamp Chestnut Oak
- Chinkapin Oak*
- Bear Oak*
- Bluejack Oak
- Sand Post Oak
- Dwarf Chinkapin Oak*
Where and When Should You Plant Oak Trees?
There are many factors to determine before planting an oak tree, or any plant at all! Where is it going, when will it be planted, and what species is best? For oaks, all these factors go hand in hand. These trees can grow large, so be sure to give your tree enough space to join the landscape seamlessly as it matures. Do not crowd it with other plants, landscaping, or buildings. If you have the resources, consider adding more than one as they will interlock their roots and be a lot less vulnerable to windstorms.
When to plant is also important, and different species thrive in different seasons. White oak acorns germinate in the fall merely days after dropping, and should be planted soon after collection. They will send down a taproot during the fall but will not appear above ground until spring. Red oak acorns, on the other hand, do not germinate until spring. They should still be collected in the fall and either planted or stored in a sealed plastic bag in the refrigerator until mid-March. Planted acorns are much more likely to be eaten by animals during the cold winter months.
Why Not Just Buy a Tree?
Doug Tallamy advocates for planting acorns or bareroot whips to grow your oaks instead of transplanting established trees. Acorns are free, plentiful, and grow to be healthier trees. Bareroot whips are dormant trees just a few feet tall. They are much cheaper and easier to transport than potted trees and can be stored a few days before planting. While planting either does not provide the instant gratification that a tree from a garden center might, they instead grant you an opportunity to watch something grow and change throughout the seasons as Doug did.
How to Plant Oaks from Acorns
- Test your acorns by soaking them in water overnight. Viable acorns will sink or remain at the bottom, while damaged or empty ones will float. Planting a floating acorn will not produce a tree. This step also rehydrates the acorns if they have been stored for a while.
- Plant in deep flowerpots instead of straight in the ground. Acorns planted directly into the ground are at a higher risk of being disturbed by the elements or taken by hungry critters. This also allows for easier monitoring and care. Use a mixture of local soil and a well-draining potting mix.
- Store the pot appropriately, exposing it to some winter cold but not freezing. And watch out for mice! To avoid desiccation (or drying out) stick to light watering once a month.
- In the spring, transplant the seedling into the ground once the first true leaves have expanded. Don’t wait too long or the plant may become rootbound in the pot. Then watch it grow!
How to Plant Oaks from Bareroot Whips
- Unpack, untangle, and soak any roots before planting. Bareroot whips can be stored for a few days before planting as long as the roots are kept moist in a plastic bag. Plant in early spring so they break dormancy and sync up with the season.
- Dig a hole 1/3 wider than the roots, as they will spread naturally from the trunk. Do not plant deeper than the crown, the area on the trunk where the roots first appear, as this is the most common way to kill your tree. Do not dig a deep hole then backfill to the appropriate depth, the backfilled soil will settle over time, resulting in a crown that settles too deep into the soil.
- Once you have found the right depth, hold your tree upright and fill the hole, jiggle the roots to ensure soil fills in all the gaps. Water generously.
- After the water has soaked in, add a layer of mulch overtop the soil. This provides some extra protection from the elements as the roots establish themselves.
- Water liberally for the first couple of days and watch it grow!
How to Protect Your Young Trees
Young trees are especially vulnerable to all kinds of critters, primarily mammals like rabbits and deer. They are not nearly as strong and sturdy as they will grow to be, and they may need a little extra help to get there! To protect from animals, Doug uses a 5 foot high circular wire cage of galvanized steel that is wide enough for the tree to extend it’s branches without interference from the cage. Other possible materials include welded wire fencing, wire mesh, or any other metal netting that can wrap around your tree. Tree tubes are another alternative that work especially well on bareroot whips. Be sure to increase the size of the cage as tree grows, and eventually remove cage for good once the tree is mature enough. Or as Doug calls it, “graduation day”!
The importance of oak trees cannot be overstated. Hundreds of animals, insects, and plants rely on them for resources and shelter. We have barely scratched the surface and hope to have inspired you to want to learn more. Doug Tallamy’s newest book, The Nature of Oaks: The Rich Ecology of Our Most Essential Native Trees celebrates oak trees and all they have to offer month by month, season by season. We hope you join us to hear his message in person! On March 4th, Doug will be our keynote speaker at the Gardening for Life Celebration. The event is full, but a waitlist has been created and we encourage those who have tickets and can no longer come to let us know and their seats will be passed on. A free livestream of Doug’s presentation will be offered for those who cannot attend, with details to come. Happy planting!