You’ve probably heard the Emerson quote, “The creation of a thousand forests is in one acorn.” Have you ever planted that acorn? What are you waiting for?! With hurricanes in the southeast, the derecho’s destruction in the Midwest, forest fires across the west, and the effects of climate change being felt worldwide, there has never been a better time to get planting!

A chestnut oak acorn (Quercus montana), like many white oaks, will germinate in fall, getting a jump start on the growing season

So what’s the first step? Acorns can be collected from the ground in the fall or picked from the tree if nearing maturity. Don’t wait too long or the local wildlife will beat you to them. When the acorn is mature, the cap should come free from the nut without tearing. After collection, acorns can be float tested to improve the rate of success. Simply toss the acorns (without caps) in a bowl of water, and discard any floaters, as these have likely become too desiccated or insect infested to be viable. If you observe any small holes in the nut, these are exit holes created by insects such as the acorn weevil larva. These are best to toss as well, as the feeding grub has likely destroyed this seed. If you don’t have many acorns, you can plant them all. They might surprise you!

White oak (Quercus alba) acorns, demonstrating good seed vs. an acorn that has been damaged by a larva.

At this point the acorns can either be planted or placed in cool storage for later planting. Many species require stratification over winter before they will germinate, so this step is important. If planted immediately, the pots will need to be placed somewhere that they will be exposed to cold, but not excessively cold. An unheated garage or shed will work. To store, nuts can be sealed in a plastic bag and kept in the refrigerator until closer to spring. Sand or sphagnum is often added to the container to inhibit mold growth. It is a good idea to check on the seeds periodically for mold.

When ready to plant, choose pots with good drainage holes and a soil medium that will also drain well. Any standard potting mix will do. We choose to add 50 % sand to our mix, for improved drainage and weight. Fill the pot, lightly pressing to settle the soil and leaving an inch or so at the top to allow for watering. Plant the nut on its side, covering with about half an inch of potting soil. Water well and keep moist but not waterlogged. Be sure to protect the pots from hungry rodents! We cover all seed trays and pots with half inch hardware mesh, secured over the edge, to keep chipmunks and mice from wrecking havoc. Those pesky critters will even uproot young seedlings to eat the remains of the seed. Throughout the growing season, keep seedlings evenly moist, and position where they will receive direct sunlight for most of the day. In late fall, the wire mesh can be carefully removed, when the trees are about to lose their leaves and go dormant. At this point, seedlings can be planted in a permanent location with plenty of mulch and protection from wildlife, or stored in a cool, protected place for spring planting. Good luck and feel free to reach out to us with your tree growing question!

New oak seedlings, protected from rodents with hardware mesh.


Grow Your Own Oaks!
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