Oak trees were traditionally used for timber to build ships, houses, and furniture. But now, they are often grown in public properties because of their charm and massive size.
A towering oak tree brings grandeur, cool shade in the summer, and vibrant fall colors to your private sanctuary. These trees are not only stunning, but their massive root systems protect watersheds and topsoil. Here's how to grow oak trees:
When To Plant Oak Tree
There are few ways you can plant oak tree but the most common methods are acorn and sapling planting. Acorns and saplings need to be planted at different times.
The best time to plant acorns is typically in the fall, shortly after they have fallen from the parent tree. This timing allows them to undergo a natural cold period that aids germination.
Certain species, such as white oaks, germinate immediately and can be planted directly in the ground soon after collection. Other species, like red oaks, benefit from a cold storage period (stratification) before planting in the spring.
Sapling planting
Saplings should be planted in the spring or early fall. These seasons provide cooler temperatures and more moisture, which helps the sapling establish its roots before the hot summer or cold winter.
Where To Plant
Where you plant your oak trees is equally important as when you plant them. Oaks need at least 6-8 hours of direct sunlight daily and well-draining soil for optimal growth. Apart from soil and sunlight, oak trees need space.
Oaks trees can grow large. Before planting one, think about how wide it will grow as an adult. Depending on the kind of oak you choose, leave at least 20-40 feet of space between it and your house, power lines, or driveway so there is plenty of room for both to grow happily.
To grow an oak from acorn successfully, you must start by choosing the acorns. The quality of acorns can significantly impact the germination rate and health of the future tree. The best time to collect acorns is after they fall from the tree in early to mid-autumn, as they are fresh and healthy.
Fresh, healthy acorns are intact and firm with smooth, unblemished surfaces. They are free from cracks, holes, and signs of rot. They will also sink in water. Avoid ones that float and have insect holes.
Stratification
Depending on the variety you are growing, some acorns can be planted immediately, while others need to be stratified. This process simulates winter conditions and helps acorns germinate.
Those that need to be stratified should be exposed to cold temperatures for a certain period. For that, place acorns in a moist container with sand or potting mix and store them in a refrigerator for 2-3 months.
Planting
You can plant acorns directly in the ground or pots. If using pots, choose ones that are deep enough for root growth. Pots with 2 .5 x. 2.5 x 3.5-inch measurements are ideal.
Fill the pots with good quality potting mix. Place the acorn 1 to 2 inches deep with the pointed end facing down. Water them well until water runs out of the drainage holes.
If you are planting in the ground, dig a hole 1-2 inches deep with a trowel. Place the acorn in the hole, with the pointy end facing down.
Protection
Acorns are a valuable food source for wildlife. Deers, rabbits, and other leaf-eating animals love to nibble on young tree trunks and branches.
This can damage the developing bark, hinder growth, or even kill it in severe cases. You may need to use protective cages or netting to protect the plants.
Transplanting
If you have grown your acorn, you need to transplant it outside. The best time to transplant is in early spring before new growth begins.
Water the potted oak seedling thoroughly a day or two before transplanting.
Carefully tip the pot on its side and gently slide the root ball out. Try not to disturb the roots more than necessary.
If the roots seem compacted or circling the pot, gently loosen them with your fingers.
Place the sapling in the planting hole, ensuring the root flare sits slightly above the surrounding soil level. Avoid burying the trunk.
Fill the hole with the dug-up soil, gently tamping it down to remove air pockets and ensure good contact between the roots and the soil.
Water the transplanted oak thoroughly, soaking the soil around the base.
How To Care For Oak Trees
Sunlight
Most oak varieties flourish in full sun, requiring at least 6-8 hours of direct sunlight each day. This sunlight supports their growth processes, such as photosynthesis, where they convert sunlight into energy.
While full sun is optimal, some oak species can tolerate partial shade, managing with 4-6 hours of direct sunlight, though their growth may be slower and they may not reach their full potential. Signs that an oak is not getting enough sunlight include leaning growth, sparse foliage, and slower development.
Soil
Oaks can grow in different types of soil but have some preferences for the best growth. The most important thing is that the soil drains well since oaks do not like being in wet or soggy conditions, which can cause root rot.
Choose soil that lets water drain easily. While oaks can handle a range of soil types, they generally prefer slightly acidic soil with a pH between 6.0 and 7.0. They do not need very fertile soil; in fact, soil that is too rich can make them grow too many leaves instead of strong roots. Average, well-draining soil works just fine for oaks.
Watering
Young oak trees need consistent watering as their roots develop. In the first year, water them regularly, especially in hot and dry conditions, keeping the soil moist but not soggy. Check soil moisture by inserting your finger a few inches into the ground.
As the tree grows and its root system establishes, gradually reduce watering frequency. Mature oaks are drought-tolerant, with deep roots to access water reserves.
During normal rainfall, they do not need extra water, but in prolonged dry periods, occasional deep watering every 7-10 days can be beneficial. Focus on soaking the root zone thoroughly rather than frequent shallow watering.
Healthy, mature oak trees in natural settings usually do not need extra fertilizer. They benefit from the natural cycle of falling leaves decomposing and returning nutrients to the soil, feeding the tree's roots.
However, there are times when fertilizing might help:
If your oak tree shows signs of nutrient deficiency, like stunted growth, small leaves, or pale color, fertilizing can be beneficial.
For young oak trees (under five years old) that are still establishing themselves, controlled fertilization can promote healthy growth.
If your oak tree is dealing with disease or environmental stress, fertilization can help the tree recover.
Mulching
Mulching is highly beneficial for oak trees as it helps retain moisture, suppress weeds, regulate soil temperature, and improve soil quality.
Here are some guidelines for proper mulching:
Use coarse, organic mulch like shredded bark, wood chips, or composted pine needles.
Avoid fine mulches like sawdust or grass clippings, which can compact and block air circulation.
Apply a 2-3 inch layer of mulch around the tree base.
Keep mulch from directly touching the trunk to prevent moisture buildup and rot.
Extend the mulch to the area under the outermost branches to benefit the root system fully.
Pruning
Pruning oak trees is beneficial for their health and structure. It shapes the tree, improves airflow and light penetration, reduces weight and wind resistance, and ensures clearance for buildings, power lines, or walkways. The ideal time to prune oak trees is late fall to late winter.
How to prune oak trees:
For young trees, focus on removing small branches (less than 1 inch in diameter). Do not remove more than a third of the canopy at a time.
Make clean cuts using sharp bypass pruners or loppers. Cut branches just outside the branch collar. Avoid cutting right next to the trunk or stubs, which can hinder healing.
For larger branches (over 1 inch in diameter), consider hiring a certified arborist.
They have the expertise and equipment to make proper cuts and minimize the risk of damage to the tree.
Harvesting Oak Acorns
Harvesting oak trees for acorns involves careful planning and sustainable practices to ensure the longevity of the trees.
Timing and Selection
The best time to harvest oak acorns is during the fall when they naturally fall from the trees. Mature, viable acorns are typically brown and smooth.
When selecting acorns, look for those that are intact and free from cracks, holes, or signs of mold. Collect acorns from various oak trees to ensure genetic diversity in your planting efforts.
Collection Methods
Gathering acorns can be done by hand or with simple tools like rakes and tarps. Spread a tarp under the oak tree to catch falling acorns, or use a rake to collect them from the ground.
For larger-scale collection, some use mechanical harvesters that gently shake the branches, causing acorns to drop onto collection surfaces below. Ensure that acorns are collected promptly to avoid damage from pests or weather.
Varieties To Grow
If space is not a problem, you can grow large varieties like Laurel, Cherry Bark, and Black oak. These varieties grow up to anywhere from 40 to 80 feet tall. If you have a smaller yard that cannot accommodate these larger varieties, you grow smaller species.
Bear Oak
This oak can be a bush or a small tree, growing up to 15 to 25 feet tall when fully grown. It has tough, leathery leaves and produces acorns that animals love to eat.
This slow-growing tree only grows to be about as tall as a two-story house with a rounded crown. It does not need a lot of sunshine and offers beautiful fall foliage.
Sand Post Oak
This oak tree is perfect for hot, sunny areas with little rain. It only grows about 20-30 feet tall and has a wide, open canopy that lets lots of light through. It does not need much water and grows quickly compared to other oak trees.
Willow Oak
This adaptable oak grows 40-50 feet tall and has branches that droop gracefully like a weeping willow. It tolerates a variety of soil conditions and provides dappled shade.
Muscadine Oak
This small evergreen oak tree will not take over your yard. It only grows about 8 to 12 feet tall and has shiny leaves that stay green all year round. It can handle salty air, making it great for planting near the coast.
About Oak Trees
Oaks are part of the genus Quercus, like beeches and chestnuts. They are native to different parts of the Northern Hemisphere. There are over 600 species with unique characteristics.
Some oak trees commonly grown in private properties include pin, scarlet, and English oak. The pin and scarlet oak have a conical outline and turn vibrant red in autumn, while the English oak is broad spreading and has yellow leaves in autumn.
Oak trees can live for over 1,000 years, making them some of the longest-living trees. They typically reach maturity around 40 years old and begin producing acorns. When they reach 150-300 years old, they are classified as veteran trees.
