If you have an oak tree or regularly visit a place where they grow, you have probably seen large amounts of acorns that have fallen to the ground nearby the tree or trees around late September through the beginning of November. It boggles the imagination that a tree so tall and sturdy as an oak started as one of those acorns.
If you don’t have an oak tree present on your property and you want one, September to November is the best time to harvest acorns from the ground and then plant one later. Look for acorns that are plump and large and avoid acorns that appear damaged, are rotting or appear sick.
You can grab a few of the nuts that have fallen onto parking lots or clear patch of ground and put them in a polyethylene plastic bag for storage. A bag that is about 10mm thick would be ideal. Place damp peat mix or sawdust into the bag with the acorns to help keep them fresh. The polyethylene plastic bags are ideal for storing acorns because they are porous enough to allow carbon dioxide and oxygen in and out and yet keep moisture out.
The bag of acorns should be stored in a refrigerator with the temperature set at 40 degrees. Acorns from white oaks can sprout at temperatures between 36 degrees and 39 degrees. Check on them during the winter and be sure that they stay just barely moist.
The red oak variety of acorns requires about 1,000 hours of cold or about 42 days. The ideal time to plant them is late April. However, they can be planted a little later or immediately after harvesting with no time spent in the refrigerator.
Preparing Acorns For Planting
As you wait to plant them, be sure that the acorns don’t dry out over an extended period of time and don’t allow them to heat up. Acorns won’t be able to germinate very quickly if they dry out.
White oak acorns can be planted in the spring. These species include white, burr, chestnut, and swamp oak.
Red oak acorns should be planted in the following spring or two growing seasons after harvest.
Planting An Acorn
The growing of an acorn should be started indoors. Plant one in a small container about the size of a yogurt cup. Poke holes in the bottom of the planter before installing the acorn to ensure adequate drainage. Plant the acorn in an equal mixture of potting soil and peat moss. The planter should be filled with the soil and peat up to its top.
Insert the acorn into the mixture of soil and peat near the top of the container. Make sure that the acorn is totally covered with peat and soil. Place the acorn horizontally. In other words, direct the cap and tip toward the sides of the planter.
Place the container with the acorn in a sunny location near a window and wait for it to grow. While you’re waiting make sure that the dirt remains moist, but not soaked. Definitely do not let the soil dry out.
You should observe a sprout within a week or so. In May the seedling will be a half-foot tall and include leaves. It is at this point that you can introduce the sprout to the outdoors.
Once the tree has sprouted a second set of leaves, place the container outside during the day. Bring it back indoors at night.
The tree should be transplanted into a 10-inch to 12-inch container in June. Use the same soil mixture as you did to start the acorn and be certain that the container provide proper drainage. At this point, the tree can be left outside.
The tree should be ready to be planted outside in the ground by fall. Select a spot that offers enough space for the roots to spread out. The oak will grow slowly. But it will be massive some day. Make sure that the tree is planted into quality soil and apply an adequate amount of mulch around it. If the sapling can’t strand straight up on its own, consider staking it.