If you are looking for one of the best purple foliaged Japanese maples, then Acer palmatum ‘Emperor I’ could be the perfect choice.
The foliage is a deep red to purple and holds its colour well into autumn. Compared to its main rival ‘Bloodgood’, it is slightly faster growing and leafs out 2–3 weeks later. This makes it an excellent option for frost-prone areas, as the delayed growth helps avoid late frost damage.
‘Emperor I’ also holds its foliage 2–3 weeks longer into autumn, extending seasonal interest. It provides strong contrast against green plantings, with a richer red tone than many other varieties. It copes well with hot Australian summers when given adequate moisture.
At maturity, it will reach around 5 metres in height with a similar spread, so allow space for it to develop its natural form.
Why Choose Acer palmatum ‘Emperor I’
- Later leafing helps avoid frost damage
- Longer autumn colour display
- Richer red foliage than many cultivars
- More heat tolerant than other Japanese maples
- Ideal for feature planting in small to medium gardens
Landscaping Uses
Acer palmatum ‘Emperor I’ works beautifully as a feature tree where its foliage colour can contrast with surrounding greenery.
- Use as a focal point in garden beds
- Ideal for courtyards and smaller gardens
- Suitable for Japanese-style gardens
- Can be grown in large containers
- Pairs well with ferns, moss, and low-growing shade plants
Growing Conditions
How to Plant
Plant in a well-drained, humus-rich soil. Dig a hole twice the width of the root ball and improve the soil with compost before planting. Position the tree so the root ball sits level with the surrounding soil, then water in well.
Choose a position protected from strong winds and harsh afternoon sun, especially in hotter inland areas.
How to Grow
‘Emperor I’ prefers a sheltered position with morning sun and light afternoon shade. It will tolerate full sun in cooler climates like Melbourne, provided soil moisture is maintained.
Mulch around the base to keep roots cool and retain moisture, keeping mulch away from the trunk.
Care Guide (Including Underplanting)
This is a relatively low-maintenance tree once established, but it performs best with consistent care during early growth.
Watering
Water deeply during dry periods, especially through summer. Young trees benefit from regular watering, while established trees need occasional deep watering during extended dry spells.
Fertiliser
Apply a slow-release fertiliser in early spring. Avoid high-nitrogen fertilisers, as these can promote excessive soft growth.
Pruning
Minimal pruning is required. Remove dead, damaged, or crossing branches in winter while the tree is dormant.
Underplanting
Underplant with shade-tolerant species such as:
- Liriope
- Ferns
- Heuchera
- Low-growing grasses
These help retain soil moisture and enhance the layered look.
Summary (Quick Facts)
- Botanical name: Acer palmatum ‘Emperor I’ (also known as ‘Wolff’)
- Foliage: Deep red to purple from spring to autumn
- Height: 5–6 metres (smaller in containers)
- Spread: Around 5 metres
- Growth rate: Medium
- Soil: Well-drained, humus-rich
- Position: Full sun to light shade
- Climate: Suitable for temperate Australian gardens
Where To Buy
Available from specialist nurseries and online plant retailers across Australia. Look for grafted, well-established plants for best results.
Est. in 1994, we offer over 30 Varieties of quality 2nd year grafted Japanese Maples (Acer palmatum) available for mail order.
www.maplesxmail.com.au
