Bur oak
Quercus macrocarpa · Fagaceae
The gardener's calendar
In autumn, ease off feeding and take the chance to clean up around bur oak and prepare for winter.
ID card
- Foliage
- Deciduous
- Flowering
- Spring (insignificant flowers)
- Adult size
- 15 to 20 m height, 12 to 15 m width
- Growth
- Moderate to slow
- Hardiness
- Very hardy, down to -30°C
- Origin
- North America (east and central)
- Soil type
- Well-drained, tolerates dry to wet soils
Care
Exposure
Plant your bur oak in full sun for optimal growth and balanced form. It tolerates partial light shade but develops denser foliage and a more compact structure in direct sunlight.
Soil and drainage
This oak adapts to many soil types, from calcareous to slightly acidic. Ensure good drainage to prevent root suffocation. Once established, it tolerates dry periods well thanks to its deep root system.
Watering
Water regularly for the first three years after planting to encourage rooting. Once established, the bur oak is very drought-tolerant and needs little watering. Adjust watering during extended heat waves.
Pruning and structure
Perform light formative pruning in the early years to guide growth. Then remove dead or crossing branches in winter. The natural form is well-branched; excessive pruning is not necessary.
Fertilization
No fertilizer is generally necessary. Apply well-decomposed compost around the base in the early years to enrich the soil and retain soil moisture.
Health and prevention
The bur oak is very robust and rarely susceptible to major diseases. Watch for powdery mildew and cankers during very humid conditions. Good sun exposure prevents most fungal problems.
Did you know?
The bur oak lives up to its name: it produces the largest acorns in North America, measuring up to 5 cm long and capped with a massive, fringed cupule that is very characteristic. These acorns are an important nutritional source for wildlife. Native Americans have used this oak for centuries for its hard wood and food resources.
Where to buy it
Best planted in autumn so the roots settle in before summer, or in early spring once the frost has passed. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, October, November.
Add this plant to my garden →Plants from the same family
- Pedunculate oakQuercus robur
- European beechFagus sylvatica
- Sessile oakQuercus petraea
- Sweet chestnutCastanea sativa
- Downy oakQuercus pubescens
- Holm oakQuercus ilex
Tips generated and checked by Viridia — adapt them to your local climate.