Siberian Iris Planting & Growing Guide

Stunning is a total understatement! Siberian Irises are pretty, prolific, and remarkably easy to grow in an array of conditions. The flowers arrive in spectacular colors with intricate markings and exquisite form. Not to mention, their strong, upright stems provide an incredible architectural element. If you haven't tried these yet, slip a half dozen into that little bare spot you keep thinking about filling and come spring, you'll have beautiful blooms that don't require spraying, deadheading, or staking! Nice, huh? Learn more with this comprehensive guide.

  • Planting Depth
  • Planting Proximity
    24" Apart
  • Planting Season
  • Plant Benefits
    Cold-tolerant and versatile garden plant.
  • Water Quantity
  • Bloom Season
    Late Spring through Summer
  • Sunlight Quantity
    Full Sun
  • Hardiness Zones
    Zones 3-8

Additional Growing Information

Where to Plant

Siberian Irises will happily flourish in both garden beds and containers when given plenty of sunlight and soil with an average amount of moisture. While they will grow in partial shade, the blooms will be more plentiful with stronger light. Additionally, in warmer areas they will tolerate wetter soils, such as on the edge of a pond, but do not do well in consistently soggy soil.

When to Plant

Siberian Irises can be planted anytime from spring to fall, with foliage forming in the autumn and taller growth emerging in the winter. These plants develop into sizeable clumps over time and bloom from late spring to early summer.

How to Plant

  • Soak the roots and rhizomes in water overnight before planting.
  • For outdoor landscape planting, find a spot with moist (but not soggy) soil and plenty of sunlight. Dig holes 3–5" deep and 12–15" apart, tucking each plant in with the roots fanned slightly and pointing downwards. The junction point between the fan and the roots should be 1–2" below soil level.
  • For container planting, start with good quality, well-draining potting soil and containers with adequate drainage holes. Dig holes 3–5" deep and 8–12" apart, tucking each plant in with the roots fanned slightly and pointing downwards. The junction point between the fan and the roots should be 1–2" below soil level. Site your containers where they will receive full-day sun.
  • Pat the soil firmly around each plant.
  • Mulch after planting to retain moisture and prevent winter heaving.
  • Water thoroughly, soaking the soil to settle it around the bulbs.

How to Grow

  • Keep your plants well-watered until established, with an estimate of about 1–1.5" of water per week for ground-planted bulbs and 1–2" per week for container-planted bulbs. Continue to water as needed during active growth periods.
  • Leave the foliage in place after blooming has finished for the season. The leaves will provide strong vertical interest while gathering sunlight to create food through photosynthesis, strengthening the plants for the future.
  • Remove the dry foliage when the leaves turn yellow and die back as the plants slip into dormancy in the fall. In warmer regions, the foliage may stay green year-round.
  • Allow your Siberian Irises to rest for a few months before beginning their next growing cycle.

Siberian Iris Tips & Tricks

  • Add some compost, decomposed manure, or leaf mold if your soil is lean or sandy, as Siberian Irises fancy soil with some humus.
  • Be mindful that these plants struggle in the hot, dry climates of the desert Southwest.
  • Expect your Irises to be shipped with green leaf fans and soil washed from the roots, so you won't risk introducing any diseases into your garden.
  • Feel free to snip flowers for colorful bouquets when in bloom, as doing so will not hurt the plants.
  • Plant your Siberian Irises in large containers, as they're rather tall and slim.