Oak trees are majestic trees that provide beauty, shade, and wildlife habitat. Their stately presence graces landscapes across the country. Traditionally, oaks are thought of as large forest or landscape trees. However, did you know you can also grow oak trees in pots?
With careful selection and proper care, oak trees can thrive in containers Growing oak trees in pots opens up new possibilities for gardens of any size Read on to learn everything you need to know about successfully planting oak trees in pots.
Why Grow Oak Trees in Pots?
Here are some of the top reasons to consider planting oak trees in containers
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Size control – Growing oaks in pots restricts root growth, controlling the tree’s ultimate size. This allows oaks to be grown even in small gardens.
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Mobility—Potted oaks are easy to move to take advantage of changing sun patterns or to keep trees safe from bad weather.
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Oak trees in pots can be used as living sculptures, accents, or focal points of foliage in garden designs. Their form and leaf shapes add interest.
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Wildlife appeal – Container oaks produce the acorns and foliage needed to attract birds and other wildlife to urban and patio gardens.
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Novelty: Oak trees in pots are a great way to start a conversation on a deck or balcony. It’s strange to see a big oak tree growing in a pot.
Choosing the Right Oak for Containers
Not all oak species are well suited to life in a pot. Here are top options that are naturally compact or respond well to container confinement:
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Dwarf chinkapin oak: This oak grows slowly and only gets 4 to 8 feet tall when it’s fully grown, making it perfect for pots.
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Dwarf bur oak – Another compact oak, it tops out around 8 feet tall and 5 feet wide.
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Willow oak – A fast-growing southern oak that adapts well to containers. Ultimate height is 40-60 feet.
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Shumard oak – Known for its colorful fall leaf display. It matures at 40-60 feet high.
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English oak – A compact English oak, slowly reaching just 15-25 feet tall.
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Japanese evergreen oak – An attractive container specimen with glossy, evergreen leaves. Grows 20-25 feet tall.
Selecting the Right Container
To support healthy oak growth, choose an appropriately sized container with these features:
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Depth – Pick a pot at least 2 feet deep to accommodate taproots.
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Drainage – Ensure pots have ample drainage holes to prevent waterlogging. Add extra holes if necessary.
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Sturdy material – Choose thick, durable containers that won’t easily crack or warp under the tree’s weight.
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Size – Select a container that is 2-3 times wider than the oak’s root ball. This will leave room for root growth.
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Insulation – For colder climates, pick pots with thick, insulating walls to protect roots from freezing.
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Weight – Bear in mind the filled pot’s weight if used on a balcony or roof deck.
Site Selection
To keep your potted oak thriving, situate it in a spot with these conditions:
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Sun – Oaks need at least 6 hours of direct sun daily. More sun results in stronger growth.
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Shelter – Protect the oak from strong winds which can rapidly dry out potting soil.
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Stable surface – Place pot on a flat, stable base like pavers or a pot feet to prevent tipping.
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Seasonal protection – In cold climates, situate pots near buildings to shield roots from harsh winter winds and low temperatures.
Recommended Potting Mix
Use a fast-draining potting soil blend tailored for oak trees. A good mix contains:
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1 part compost or leaf mold
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1 part peat moss
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1 part perlite or builder’s sand
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A handful of slow-release fertilizer pellets
This gives oaks the aeration and fertility they need while retaining just the right amount of moisture.
Watering and Fertilizing
Oaks in containers need different care than their counterparts growing in open ground:
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Watering – Check soil moisture daily. Water thoroughly whenever the top few inches become dry.
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Fertilizing – Apply a diluted liquid fertilizer monthly during spring and summer. Or top-dress with slow-release pellets in early spring.
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Refreshing potting mix – Every 2-3 years, remove the top few inches of old soil and replace with fresh mix to replenish nutrients.
Pruning and Maintenance
Follow these tips to keep container oaks looking their best:
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Root pruning – If roots start circling, trim them back before repotting to encourage outward growth.
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Structural pruning – Selectively prune branches to shape the oak’s canopy and enhance its form.
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Leaf cleanup – Remove fallen leaves around the base of the pot to keep pests and fungus at bay.
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Pest management – Watch for signs of common oak pests like galls, mites and borers. Address issues promptly.
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Overwintering care – In cold climates, wrap insulation around pots or shelter containers in unheated garages once dormant.
Transplanting into the Landscape
If your potted oak eventually outgrows its container, here are tips for transplanting it into the garden:
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Choose a site with full sun exposure and well-draining soil. Dig a hole 2-3 times the width of the root ball.
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Water the oak deeply a few days before transplanting.
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Carefully remove the oak from its pot and loosen any circling roots. Set it in the hole at original soil level.
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Backfill the hole with native soil, water thoroughly and apply 2-4″ of mulch around the base. Stake if needed while establishing.
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Water deeply for the first few weeks while roots recover from transplant shock.
With its graceful form and architectural presence, the stately oak tree feels right at home in landscapes of any size. By selecting compact varieties and following the best practices outlined here for container care, even the smallest garden can support a magnificent potted oak.
Growing Oak Seedlings in a Seedbed
An outdoor seedbed is a good way to produce a large number of seedlings at once. Select an area that is well-drained and in full sun. Find a small space in a flowerbed that can be used for this purpose. Make sure the area is not subject to animal browsing. An abundant squirrel population is also very detrimental, as they will dig up acorns. In addition, deer are quite fond of young seedlings, as are moles, voles, rabbits, and other mammals.
Prepare the seedbed by tilling and incorporating organic material if improved drainage is needed. Place four to seven acorns per square foot and about an inch below the ground; if the acorns are very big, plant them deeper. When planting most seeds, three times the width of the seed is a good rule of thumb.
Water your seedbed thoroughly after planting. In several days or weeks, the seed will germinate and shoots and leaves will emerge from the soil. Seedlings will not emerge at the same time; emergence will be spread over 1 to 2 weeks. Following emergence, remove smaller, inferior seedlings to encourage development of better seedlings. Make sure each seedling has enough space so that the entire stem is in full sunlight throughout the day. If rainfall is irregular, water seedlings at least once a week so that they do not dry out. Grass and other weeds must be removed as they emerge in the seedbed. If left unchecked, the seedlings will grow slowly or die under competition.
Seed Dormancy and Stratification Differences
Seed dormancy between red and white oaks differs, so the process of storage and sowing can also differ. Seed dormancy is simply nature’s way of delaying germination until more favorable conditions exist. As shown in Table 1, white oaks germinate in the fall, and red oaks germinate in the spring. Spring germination of a red oak acorn is the result of a process known as stratification, which breaks down the heavy seed coat, allowing the acorn to sprout.
Both red and white oaks can be sown immediately to outside seed beds after collection. However, red oak acorn germination will not occur until the spring following natural winter stratification.
This is why you can see white oak acorns lying on the ground with the radicle (emerging embryo) sticking out from the seed. White oak acorns don’t go to sleep. If you have decided to sow in the spring, you can store these acorns by placing them in refrigeration at 34 to 40°F in cool, moist sand, but for no longer than 3 to 4 months.
Red oak acorns: Unless immediately sown to an outside seedbed, red oak acorns need to be stratified to satisfy the dormancy requirement before sowing. Red oak acorn stratification requires cool, moist storage for 4 to 8 weeks, but they can be held in storage for up to 2½ years in specialized circumstances.
During storage, maintaining high moisture content is key to maintaining good acorn quality. Start by placing moist acorns in plastic bags (4 to 10 mil thickness), which can either be sealed or partially left open and placed in a refrigerator. Temperature should be maintained slightly above freezing, with humidity above 30 percent. Airtight storage can be damaging, so bags or containers should not be thick enough to limit gas exchange. Keep acorns moist, but do not allow them to soak in excess water. Every 2 to 3 weeks, visually examine them for fungus or mold growth. Too much or too little moisture during storage will reduce germination.
Plant either type of acorn outside in a seedbed or in containers. It is much easier to use an outside seedbed because nature will provide the right conditions most of the time, and watering will be necessary only during dry periods.
How to Grow an Oak Tree from an Acorn
FAQ
What is the best potting mix for oak trees?
What to do with potted oak trees in winter?
Encircle the potted tree with wire, like you’re building a fence around it. Drop the mulch or hay around the tree so that it is covered from the ground to the top of the pot. This insulation should protect the tree’s roots from winter’s coldest temperatures, which are the most vulnerable part of the tree.
When to plant potted oak trees?
Acorn and Seedling Planting. Acorns can be planted from early November (after the first rains have soaked the soil) until early March.
Where not to plant oak trees?
From my own experience and from what I have read in my 60 year old gardening book and online, Oak trees should NOT be planted close to the house. The Oak tree needs to have room for its far reaching branches (which means roots as well) to spread and grow without hitting the house or causing foundation issues.
How to grow oak trees in pots?
Another important supply for growing oak trees in pots is soil. It is important to use soil that is well-draining and rich in organic material. You can mix in some compost or manure to give your tree the nutrients it needs. Additionally, it is important to keep the soil moist, but not soggy.
How can I grow an oak tree from an acorn?
To grow an oak tree from an acorn, start by planting it in a small pot (6 inch). For larger acorns like bur or young grown oak, use a 1 gallon pot. Keep in mind that transferring your oak tree often can damage its roots and cause growth deficiency.
How deep should a pot be for an oak tree?
For example, if you plan to grow a large oak tree, you should choose a pot that is at least three feet wide and two feet deep. This will give the roots enough space to spread out and help the tree stay healthy. Since the soil in the pot needs to stay wet, you should water the tree often and keep an eye on the soil level.
How do you grow an oak tree?
To grow an oak tree, consider the following factors: Space (ensure the roots have enough room to grow), Water (Oak trees can consume up to 30 gallons of water at 6 feet tall), and Weather (conditions need to stay humid, too cold and the roots could freeze).
Can you grow an oak tree in a container?
If you wish to grow an oak tree in a container, it is a good idea to choose a small oak if possible. The larger the oak is, the more difficult it will be to keep it alive and deal with its nutrient and space needs. You might even want to plant an acorn in some fresh compost.
What size pot is suitable for a young oak tree?
For young grown oak, a 1 Gallon pot is suitable. Growing your oak tree from an Acorn should be kept in a small pot (6inch) for larger Acorns.