Companion plants for irises are as much a personal decision as a
practical decision. As long as they share compatible needs for light,
water and fertilizer without over crowding the high-priority irises,
they should thrive together!
Some of my favorite combinations:
Hostas, rhododendrons, azaleas and ferns mix quite well with Pacific
Coast Irises.
Alternating Daylilies and Spuria irises is a great combination. Spurias
bloom before Daylilies; their flower spike rise above the Daylily
foliage. Then, once the Spurias are done blooming and going into a
semi-dormant state, the Daylilies start blooming and their foliage hides
part of the Spuria foliage.
Iris japonica is an excellent understory plant for native
plantings, as is Iris cristata. The flower stalks extend a delicate touch color above
groundcovers and the foliage add a little height and texture during the
remainder of the growing season.
Miniature Dwarf, Standard Dwarf, and Pacific coast irises are all
excellent additions to rock gardens and low borders.