Caesar's Brother Siberian Iris

Caesar’s Brother is a historic Siberian iris introduced by F. Cleveland Morgan in 1932. Its deep purple-blue flowers rise above upright, strap-like foliage, with flowering reported from late spring into early summer and mature stems around 31 inches or taller depending on conditions ([American Iris Society](https://wiki.irises.org/Sib/SibCaesarsBrother), [Chicago Botanic Garden](https://www.chicagobotanic.org/plant-information/plant-finder/iris-sibirica-caesars-brother-caesars-brother-siberian-iris), [RHS](https://www.rhs.org.uk/plants/94586/iris-caesars-brother-sib/details)). ## Seasonal Interest The flowering stems appear after bearded irises and before Japanese irises in the Chicago Botanic Garden’s display; that garden reports bloom in May and June, while the RHS describes early to mid-summer flowering. The clump-forming leaves provide a vertical green accent after flowers fade. The cultivar’s registered history and color are recorded by the [American Iris Society](https://wiki.irises.org/Sib/SibCaesarsBrother). ## Growing Conditions Grow in full sun or partial shade in soil that stays moist but drains well. Keep newly planted clumps watered through their first season. Once established, this selection tolerates a broad range from drier garden soil to pond edges, according to the Chicago Botanic Garden. Extension and nursery profiles also describe Siberian iris as adaptable to moist, wet-site conditions and fertile garden soils ([University of Illinois Extension](https://web.extension.illinois.edu/hortanswers/plantdetail.cfm?PlantID=732&PlantTypeID=2), [Phoenix Perennials](https://www.phoenixperennials.com/plant-encyclopedia/iris-sibirica-caesars-brother/)). ## Maintenance Remove spent flower stems after blooming and cut away dying leaves in autumn. Divide crowded clumps in early autumn or spring; allow new divisions to establish before reducing irrigation. The [RHS iris growing guide](https://www.rhs.org.uk/plants/iris/border/growing-guide) gives general cultivation and division advice for clump-forming irises.