Iris: Sowing, planting and harvest calendar
How do you plant irises?
Identify your irises before choosing the planting season and depth. Bearded iris rhizomes are generally planted after flowering, from summer into early autumn. Bulb irises are usually planted in autumn. For potted plants, adjust timing to the species and avoid frost, intense heat or waterlogged ground.
Prepare a sunny position for bearded irises, with soil that drains well. Siberian irises tolerate moister ground and light shade. Remove weeds, loosen the soil and follow the cultivar's recommended spacing so the clumps can develop without excessive competition.
For a bearded iris rhizome, dig a hole wide enough to spread its roots without folding them. Place the rhizome horizontally, cover the roots and leave its upper surface partly exposed. Do not bury it like a bulb. For bulb irises, follow the packet's planting depth instead and place the pointed end upwards. Plant potted Siberian irises at the level of their root ball, following the supplier's instructions.
Water after planting to settle the soil against the roots. Check moisture during establishment and adjust watering to the group and weather. Keep the tops of bearded iris rhizomes clear, without thick mulch or compost placed directly over them.
When do irises bloom?
