Troubleshooting
Magnificent Juno Iris problems — and how to fix them
Magnificent Juno Iris (Iris magnifica) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Storage root rot at planting
The fleshy storage roots snap easily and any wound becomes an entry point for Fusarium or bacterial rot. Handle bulbs with extreme care; do not attempt to straighten or reposition roots once spread in the planting hole. Dust cut surfaces with sulphur powder before planting.
Summer bulb rot in wet climates
UK summers are often too wet for Juno irises in open ground; bulbs collapse from fungal or bacterial rot during dormancy. Lift bulbs after foliage dies, dry in a warm, well-ventilated spot, and store in dry sand or vermiculite until autumn replanting, or grow in a bulb frame.
Aphids and iris mosaic virus
Aphid infestations in spring can transmit iris mosaic virus, causing mottled, streaked foliage and reduced vigour. Control aphids with insecticidal soap sprays; remove and destroy any plants showing persistent viral symptoms.
Prevent magnificent juno iris problems before they start
Most magnificent juno iris issues are care-mismatch, not bad luck. Dial in the basics:
Magnificent Juno Iris problems — FAQ
Why is my magnificent juno iris storage root rot at planting?
The fleshy storage roots snap easily and any wound becomes an entry point for Fusarium or bacterial rot. Handle bulbs with extreme care; do not attempt to straighten or reposition roots once spread in the planting hole. Dust cut surfaces with sulphur powder before planting.
Why is my magnificent juno iris summer bulb rot in wet climates?
UK summers are often too wet for Juno irises in open ground; bulbs collapse from fungal or bacterial rot during dormancy. Lift bulbs after foliage dies, dry in a warm, well-ventilated spot, and store in dry sand or vermiculite until autumn replanting, or grow in a bulb frame.
Why is my magnificent juno iris aphids and iris mosaic virus?
Aphid infestations in spring can transmit iris mosaic virus, causing mottled, streaked foliage and reduced vigour. Control aphids with insecticidal soap sprays; remove and destroy any plants showing persistent viral symptoms.