Allium 'Globemaster' vs Ornamental onion 'Purple Sensation'
Both are purple drumsticks on bare stems in late spring. 'Purple Sensation' is the smaller and cheaper, with heads the size of a tennis ball, so it can be planted by the dozen; it seeds about gently. 'Globemaster' is a sterile hybrid with heads the size of a melon, longer-lasting, and a statement on its own.
 Allium 'Globemaster'Allium 'Globemaster' |  Ornamental onion 'Purple Sensation'Allium hollandicum 'Purple Sensation' | |
|---|---|---|
| Size | 3 ft tall, 12 in wide | 2½ ft tall, 8 in wide |
| Plant | 10 in apart | 8 in apart |
| Zones | 5 to 8 | 4 to 8 |
| Light | Full sun | Full sun |
| Soil | Dry and sharply drained, average fertility | Dry and sharply drained, average fertility |
| Flowers | Late May to late June; purple | Late May to early June; purple |
| Leaves | Bold, summer-dormant | Medium, summer-dormant |
| Job in a bed | Accent | Accent |
| Pets | Toxic (moderate) | Toxic (moderate) |
| Deer | No record | Resistant |
| Native | No | No |
| Spread | Low risk | Moderate risk |
Rows where they differ are marked. Flowering times are for zone 5.
Which to choose
- Choose ornamental onion 'Purple Sensation' for colder gardens (to zone 4) and dry summers.
Can they grow together?
Yes: they grow in the same conditions. Beside allium 'Globemaster', ornamental onion 'Purple Sensation' is in flower together for three weeks, from late May; medium leaves against its bold ones; happy in the same dry soil. They share full sun and zones 5 to 8.
Read more: all about allium 'Globemaster', and all about ornamental onion 'Purple Sensation', each with a bed the planner designed around it.