Oak trees are strong, beautiful trees that grow natively in a variety of habitats. Did you know that with just a little bit of time and luck, you can grow your own oak trees? In this article, we’ll discuss all you need to know about how to grow oak trees from acorns.
What You'll Learn Today
- How Do You Start an Oak Tree From an Acorn?
- How Do You Plant an Acorn in the Woods?
- How Long Does it Take to Grow an Oak Tree From an Acorn?
How Do You Start an Oak Tree From an Acorn?
Growing oak trees from seed is easy to do as long as you follow a few basic steps. It may take some practice to get it right, but you’ll find that acorns will sprout like weeds as long as you meet certain conditions to help them grow.
Let’s take a look at the step-by-step process for starting oak trees from acorns.
Collect the Acorns
Acorn season begins during early fall and lasts through late fall or early winter depending on your location. It’s best to collect acorns from strong, healthy trees after the acorns have begun falling from the trees.
You can gather your acorns from the ground or from the tree branches. If the caps fall off on their own or you can remove them easily, you will know the acorns are mature enough to plant.
Take care only to collect healthy, solid, undamaged acorns. Discard any acorns that show signs of mold or rot, have cracks or holes in them, or feel too lightweight.
One quick way to test the viability of the acorns is to put them in a bucket or bowl and fill it with water. Any acorns that float can be discarded, as they will not grow.
Stratify the Acorns in the Refrigerator
Once you have a collection of healthy, undamaged acorns, you’ll need to prep them for planting through a process called stratification. This process involves storing them in the refrigerator to mimic the natural conditions they would be experiencing outside.
To stratify acorns, place them in resealable bags with a little bit of peat moss, vermiculite, sawdust, or a similar soil additive. The bag should only be about half full, and the acorns should have plenty of room to breathe without being crowded.
Place your bags in the refrigerator. According to the Wisconsin Department of Natural Resources, the fridge should be set at 40 degrees Fahrenheit.
Check the bags periodically over the next 30 to 90 days, making sure the peat moss or other additive stays moist but not wet. It’s important not to let the mixture dry out.
Depending on how long you keep them in the fridge, the acorns may begin to sprout. Be careful not to damage the long taproots that form when you check the bags or remove them for planting.
Plant the Acorns
Once the acorns have stratified for at least 30 days, you can plant them in pots or directly outside. You can plant them as early as December in warmer regions, though you may want to wait until February or March in colder areas.
To plant the acorns inside, fill several 8-inch-deep or larger pots or planters with a good quality potting soil or a mix of sand, loam, and peat moss. You’ll need one pot for each acorn.
Place the acorn in the pot and cover it with about half an inch of soil. Keep the soil damp but not soaking – you don’t want to overwater oak seedlings.
It is best to start acorns inside as they are more protected from the elements and wildlife, but if you choose to plant them outside, there are some extra steps you can take to protect them.
- Plant two acorns in each spot in case one doesn’t grow.
- Use a tree protector to guard the area from invading wildlife. You can use a milk carton with the top and bottom removed in the same way.
- Keep the area well watered. You may also want to add peat moss or sawdust before planting to create looser, more well-draining soil.
How Do You Plant An Acorn Sprout Without Damaging It?
If your acorns sprouted during the stratification period, you may be concerned about damaging the tender growth when you plant the acorns.
Always handle sprouted acorns with care. Be gentle when removing a bag of sprouted acorns from the fridge, and be careful to separate each one without jostling the bag or breaking sprouts off.
To avoid breaking roots when planting, create a small hole in the soil deep enough for the longest root. Holding the acorn suspended in the hole, gently gather the soil around the root, starting at the bottom and working your way up until the seed and all of the sprouted parts have been covered.
Care for the Seedlings as They Grow
Once your acorns are planted, water them regularly but allow the soil to drain well between waterings. It may take some time before the first sprouts appear above the soil, so be patient.
After they have sprouted, you’ll want to make sure they receive full sun if you are caring for them inside. Place them in a sunny window or underneath grow lights for up to 16 hours a day.
If you planted them outside, it’s okay for them to be in partial shade, but they should still receive an ample amount of sunshine.
Seedlings kept inside can be planted in larger pots as needed. Don’t allow the taproot to grow out the bottom of the pot, and never allow a young plant to become rootbound.
If desired, you can plant your seedlings outside in spring before the summer heat has begun to set in. Otherwise, move your potted plants to a sunny area outside as often as possible so they can begin to toughen up and get used to the outdoors.
Water well throughout the spring and summer. Trees planted in the ground can be deeply irrigated from time to time–as often as every week during dry periods or in drier regions.
You may keep your potted plants in their planters as long as you want, though you may have to continue to transplant into larger pots as the trees grow. Otherwise, plant the young saplings in the ground during the fall, making sure they have at least a week or two to adjust before the first frost.
How Do You Plant an Acorn in the Woods?
Planting acorns directly in the ground in wooded areas is even easier than planting them in pots, though the germination rate may not be quite as high. Always make sure you are planting them only where you have permission to do so, such as your own property or that of a friend.
Here are some things to keep in mind when planting acorns in the woods.
There is No Need to Stratify
You can plant your acorns directly in the ground after collecting them. They will be stratified naturally during the cold winter months.
Plant Multiple Acorns
When planting acorns in the wild, many of them may be stolen by squirrels or other foraging animals. They are also more subject to mold, bug damage, and other variables that may prevent them from growing as well.
For this reason, consider planting several acorns in each spot.
Keep the Weeds Down
It’s important to keep the grass and weeds away from your tiny saplings as they grow. This way, they will receive the proper water and nutrients they need to become strong and healthy.
Water as Needed
Be aware of any dry stretches your area experiences. Young trees need plenty of water, so periods of drought and even a week or two of hot, dry weather in the middle of summer can be deadly.
When watering your young trees, make sure the water goes down deep. This will encourage the tree to send down deep roots.
How Long Does it Take to Grow an Oak Tree From an Acorn?
It will depend somewhat on your location and the specific species of oak you’re growing. But in general it takes:
- 30 to 90 days to stratify your seeds
- A few weeks to a few months for seeds to sprout
- 6 months to a year from collecting acorns to planting young saplings outside
- 20 years for the tree to begin bearing acorns
- 30 to 35 years for the tree to become fully mature
- Up to 50 years before the tree bears consistently high yields of acorns
Check out the following video to see how an acorn sprouts and becomes an oak tree.
Oak trees are easy and fun to grow from the time you collect the acorns until you plant the saplings in the ground. The next time your neighborhood oak trees start producing acorns, why not try planting a few of them yourself?