Iris: the rainbow bloom

Iris: the rainbow bloom
© GMH/Gräfin von Zeppelin

Whether a tiny, potted variety or a first-year flowering in the perennial bed, irises are always eye-catchers, and their grand variety of color will thrill avid gardeners.

There are more than 200 varieties worldwide, a number that’s constantly growing as breeders bring new types to market.

Bearded iris

Some of the most impressive types are bearded irises, which blossom in May or June. Tall and medium-sized varieties reach from 2 to 4 feet and really shine when planted in groups.

Wild types

The simpler but no less elegant blossoms of wild varieties such as the blue iris (Iris spuria) and the dalmation or sweet iris (Iris pallida) are ideal for naturalistic beds that also feature green foliage. One choice partner here is cotton lavender (Santolina chamaecyparissus) and true lavender (Lavendula). These compliment the iris leaves’ gray-green handsomely and also prefer the same conditions: sunny and mostly dry. Above all, keep these from constant moisture, which rots the rhizomes – actually thick storage organs. Don’t position irises right at the front of the bed, but rather in the second or third tier, since their leaves fade soon after the flowering period, and it’ll be up to neighboring plants to move the eye of the observer away.

Siberian iris and yellow flag

The delicate blue or violet flowers or Siberian iris (Iris sibirica) look best when planted in bunches and work beautifully with the luminous yellow blossoms of yellow flag (Iris pseudacorus). They do best at the edge of a pond, growing to just under 3 feet tall, but while yellow flag will tolerate standing water, Siberian iris will not. It can, however, thrive in normal garden soil in a sunny or partly shady spot and is a good choice for small yards.

Dwarf iris

There are many miniature iris varieties – real charmers – that haven’t yet enjoyed their fair share of attention. Netted iris (Iris reticulata), Orchis iris (Iris histrioides), and dwarf lake iris (Iris lacustris) are just a few that grow from bulbs instead of rhizomes, blooming as early as February or March. At this time of year you’ll find them as potted plants that can be placed in the yard after blooming. Just like short Iris barbata-nana, they’ll adorn any rock garden and container.

How to plant and propagate bearded iris

To grow bearded iris successfully, you’ll need to work a good amount of sand into loamy earth before planting. The rhizomes are then planted flat, leaving about the upper half exposed. A high-potash fertilizer is best for early, springtime growth. Cut wilted greenery all the way back to the soil to keep the plant from expended any unnecessary energy on seed-building.

Take note: after a period of several years, the rhizomes will have propagated in a cruciform pattern and your bearded iris will become increasingly reluctant to bloom. That’s when it’s time to divide them. At summer’s end, use a garden fork to lift the rhizomes from the soil. The sections at the edge will be the most vigorous. Sever them from the rest with a clean, sharp knife at the clearly visible connective points and plant anew; trim the leaves short to prevent the new planting from drying out before it’s had a chance to root.

Submitted by: 
greenduck

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