Endless Summer vs Nikko Blue hydrangea
Both are mophead hydrangeas, blue in acid soil and pink in alkaline. 'Nikko Blue' is the old favourite, and it flowers only on last year's stems, so after a cold winter, a late frost or a spring pruning it can be all leaves. 'Endless Summer' was the first bigleaf hydrangea sold for flowering on new stems as well as old, so it flowers even after a hard winter, for longer, and in colder zones. In mild, coastal gardens 'Nikko Blue' has the deeper blue.
 Bigleaf hydrangea 'Endless Summer'Hydrangea macrophylla 'Bailmer' (Endless Summer) |  Bigleaf hydrangea 'Nikko Blue'Hydrangea macrophylla 'Nikko Blue' | |
|---|---|---|
| Size | 4 ft tall, 4 ft wide | 5 ft tall, 5 ft wide |
| Plant | 3½ ft apart | 4 ft apart |
| Zones | 4 to 9 | 6 to 9 |
| Light | Part sun to part shade | Part sun to part shade |
| Soil | Evenly moist, rich fertility | Evenly moist, rich fertility |
| Flowers | Late June to mid September; blue, pink | Late June to early August; blue, pink |
| Leaves | Bold, deciduous | Bold, deciduous |
| Job in a bed | Anchor | Anchor |
| Pets | Toxic (mild) | Toxic (mild) |
| Deer | Not listed as resistant | Not listed as resistant |
| Native | No | No |
| Spread | Low risk | Low risk |
Rows where they differ are marked. Flowering times are for zone 5.
Which to choose
- Choose bigleaf hydrangea 'Endless Summer' for colder gardens (to zone 4) and a longer show (13 weeks of flower against 7).
Can they grow together?
Yes: they grow in the same conditions. What bigleaf hydrangea 'Nikko Blue' brings beside bigleaf hydrangea 'Endless Summer': in flower together for seven weeks, from late June; happy in the same moist soil. They share part sun and part shade and zones 6 to 9.
Read more: all about bigleaf hydrangea 'Endless Summer', and all about bigleaf hydrangea 'Nikko Blue', each with a bed the planner designed around it.