Stairway to Heaven Bearded Iris

Bearded iris rhizomes are simple to plant, but they have one rule that matters most: plant shallow and keep them well drained. Unpack your rhizomes as soon as they arrive and plant within a few days.

Planting

1. Unbox right away. Remove the rhizomes from the packaging and store them in a cool, dry, airy spot until you can plant. They should feel firm.
2. Pick a bright spot. Choose a site with full sun to part shade, aiming for at least six hours of direct sun for the heaviest bloom.
3. Loosen the soil. Work the top 8-10 inches of soil and mix in compost or coarse sand if drainage is slow. Iris rot in soggy ground.
4. Set the rhizome shallow. Dig a shallow hole with a small ridge in the center, rest the rhizome on top with roots fanned down each side, and cover so the top of the rhizome sits at or just below the soil surface.
5. Space 24 inches apart. Point the leaf fan in the direction you want the clump to grow and firm the soil gently around the roots.
6. Water in once. Soak the planting area to settle the soil, then hold off until the soil dries.

Watering

• Go easy. Water about once a week during the first growing season only when the top inch of soil is dry.
• Established plants. Mature clumps are drought tolerant and usually need water only during long dry stretches.
• Skip the overhead soaking. Water at the base to keep the rhizomes and foliage dry.

Feeding

• Feed in early spring. Apply a low-nitrogen fertilizer, such as a 5-10-10, as new growth appears.
• Second light feeding. A small application right after bloom supports next year's flower buds.
• Avoid high nitrogen. Too much nitrogen produces floppy leaves and encourages rhizome rot.

Mulching

• Keep mulch off the rhizome. Mulch between plants for weeds, but leave the rhizome tops exposed to sun and air.

Pruning & Dividing

• Deadhead spent stems. Cut flower stalks down to the base once blooming finishes.
• Tidy the foliage in fall. Trim leaves back to 6 inches and remove any dead material to reduce overwintering pests.
• Divide every 3-4 years. In late summer, lift crowded clumps, cut the rhizomes into pieces with roots and a leaf fan, and replant.

How do I plant the rhizome so it actually blooms?

Plant it shallow. The top of the rhizome should sit at or barely below the soil surface with the roots spread downward. Rhizomes buried too deep produce leaves but few or no flowers.

When will it bloom after planting?

Stairway to Heaven flowers in early midseason, typically late spring around May. Rhizomes planted in fall usually bloom the following spring, while spring-planted rhizomes may take a season to settle in before blooming heavily.

Are bearded iris deer and rabbit resistant?

Yes, bearded iris are among the more deer- and rabbit-resistant perennials. The foliage and rhizomes are unpalatable to most browsing animals, though no plant is completely immune.

Is this iris toxic to pets?

Iris rhizomes and foliage can cause stomach upset, drooling, or vomiting if chewed by cats or dogs. Plant where curious pets don't dig, and contact your veterinarian if a pet eats any part of the plant.

Does it need winter protection?

In zones 4-9 it overwinters in the ground with no special care. In the coldest zones, add a light layer of straw or evergreen boughs after the ground freezes the first winter, then pull it back in early spring.

Can I grow it in a container?

Yes. Use a wide pot at least 12 inches deep with fast-draining mix and keep the rhizome top exposed. Containers in zones 4-5 do best moved to an unheated garage or sheltered spot for winter.