How to grow and care for a red oak tree

Oaks are among the most widespread tree species worldwide, with over 600 recognised species. They hold significant cultural and ecological importance, often appearing in myth, legend and folklore. Oaks are highly valued for their utility to humans and their crucial role in supporting wildlife.

The red oak tree is native to North America but is found across continental Europe and the UK.

Identifying a red oak tree

Red oak trees are known for their impressive size and can grow up to 22m tall with a spread of 15m. They typically develop a broad, rounded crown and have a moderate to fast growth rate. The leaves of red oaks are held in an alternate pattern on stems and are deeply lobed with pointed tips. They turn vibrant shades of red in autumn.

Value to wildlife

Oak trees are renowned for the number of wildlife species they support. However, as it's not native to the British Isles, red oak doesn't support as much wildlife as our native oaks, but is still popular with nesting birds and pollinators.

How to grow a red oak tree

Grow red oak in moist but well-drained, acidic to neutral soil, in full sun to partial shade.

Where to grow a red oak tree

Grow red oak as a standalone feature in a very large garden. Make sure you select a suitable location that allows for its ultimate size and spread, but where you can enjoy its impressive autumn colour. Ensure the area has enough space for the tree to grow without being obstructed by buildings or other structures.

How to plant a red oak tree

Red oaks are available as bare roots (without soil around the roots) or pot-grown trees. Dig a square hole that's wide and deep enough to accommodate the rootball or roots of the tree.

If planting a pot-grown tree, gently remove it from its container and place it in the hole, making sure it is planted at the same depth as it was previously. Once you're happy with this, take the tree out of the hole and hammer in a short stake at a 45-degree angle so it goes into the soil a good 40cm from the trunk but crosses over with it at about 40cm from the ground, but with plenty of space between the two so there's no rubbing. Then replace the plant and backfill with soil, firming in well, and secure the tree to the stake with a tree tie.

If planting a bare-root plant, use the soil 'tide mark' towards the base of the stem to assess how deep it was previously planted, and ensure it remains at this depth in its new hole. Make sure you're happy with how the plant looks at this stage and then position your stake vertically about 10cm from the trunk. Then remove the tree and hammer the stake in deeply, making sure it's nice and straight. Once it's firmly in place, return the tree to the planting hole in the same position it was originally and backfill with soil, firming around the roots to eliminate air pockets. Finally, secure the tree to the stake with a tree tie.

Whatever method you use, water the tree thoroughly after planting and apply a mulch to hold in moisture and hold back weeds.

Can you grow a red oak tree from an acorn?

To grow red oak trees from acorns, start by collecting mature acorns from a healthy red oak tree in autumn. Choose acorns that are plump and free from any visible damage or pests. Plant them in a container of peat-free compost or a prepared bed of well-drained soil, burying them about 3cm deep. It's a good idea to plant a few acorns to increase the chances of successful germination.

It is highly advisable to protect your pots from squirrels by covering them with chicken wire or another suitable lid.

Keep the soil consistently moist but not waterlogged during the germination process. Red oak acorns usually take several weeks to germinate. Move them to a larger pot once they have grown to about 15cm tall.

How to care for a red oak

To care for a red oak tree, provide regular watering during dry periods in the first few years of establishment. Apply a layer of organic mulch around the base of the tree to conserve moisture and suppress weeds.

How to prune a red oak tree

Red oaks may need occasional pruning to remove dead wood and maintain and open, airy shape. This is best done during the dormant season, typically in late winter or early spring before new growth begins.

• Start by assessing the tree's structure and identifying any dead, diseased or damaged branches. These should be removed first to prevent further spread of diseases or potential hazards.
• Next, look for any branches that are crossing or rubbing against each other. Select one branch to keep and remove the other to maintain proper spacing and prevent damage.
• Remove any branches that are growing towards the centre of the tree or are causing overcrowding. This will help improve air circulation and sunlight penetration throughout the tree.
• Maintain a central leader or main trunk by removing any competing leaders or branches that are growing upright and could potentially create structural problems in the future.
• When making pruning cuts, use clean, sharp tools to make clean cuts just outside the branch collar, which is the swollen area where the branch attaches to the trunk. Avoid leaving stubs or cutting too close to the trunk.
• Avoid heavy pruning or removing a large percentage of the tree's canopy at once, as this can stress the tree and negatively impact its health.

If you are unsure or have concerns about pruning, it's best to consult with a certified arborist or professional tree care service.

Pests and diseases

As red oak tree is not native it will support fewer insects than our English and sessile oaks. However, any insects that you do find on the leaves will be using it to complete their lifecycle and should be left alone unless present in huge numbers. Birds and other predators will control them naturally, using them to feed their young.