Every garden should contain a variety of iris. Named for the Greek goddess of the rainbow, iris come in a broad range of colors, with the exception of a bright red. There are many thousands of iris, with new ones being introduced each year. Many people don’t realize that iris are beautifully scented.

There are many kinds of iris, starting with spring’s earliest bloomers, iris reticulata, which grow from fall-planted bulbs. Next is the dwarf-bearded, iris pumila, which grows from a rhizome just like its tall bearded cousin. Next are the intermediate bearded iris. My neighbour has a clump of yellow intermediate iris which is really lovely, proving that iris look much better if there is a mass planting. The intermediate iris are followed by the best-known iris, the tall-bearded iris, iris germanica. Blooming at about the same time as iris germanica is the Siberian iris, another tall, hardy species, which grows from fibrous roots and likes to live in part shade. When you buy iris it’s important to note the bloom time, usually marked as E (early), M (midseason), or L (late). If you have some of each, it will extend your bloom season and give you more time to enjoy them.

It’s worth it to come into nurseries in late May and early June to see the beautiful iris hybrids in bloom. They surpass the old varieties in so many ways — colors, ruffles, fragrance (many old varieties smell like grape kool-aid), and number of buds per stem. There are some wonderful iris websites such as Ferncliff Gardens in Mission and Schreiners in Oregon where you can order catalogs. Schreiners is the largest iris producer in North America and a leading hybridizer. They have won many awards. If you look at “Collectors” or “Fancier” catalogs you’ll see that some of the newest iris, just very small divisions, can cost hundreds of dollars.

The following instructions apply to the iris which grow from rhizomes, such as the dwarf, intermediate, and tall bearded iris. Iris may be planted in early spring or after blooming in July, August, or early September. It is important that the roots of newly planted iris be well established before the growing season ends. This can cause a problem if you are ordering iris from mail order catalogs as they often arrive near the end of September or even in October.

Iris need at least a half day of sun and the soil must have good drainage! Iris may be planted in borders, raised beds, or on slopes, but if the soil is too wet, they will rot. As they are shallow-rooted, some protection from heavy wind is advisable. After blooming the iris can be fed with a 6-10-10 fertilizer. Avoid fertilizers with a high nitrogen count. You can also feed with bonemeal or superphosphate. Don’t fertilize in the fall as you don’t want to have soft new growth going into the winter.

Plant iris 12 to 24 inches apart. Closer planting gives an immediate show, but you will have to divide and thin your iris more often.

They should be planted so that the tops of the rhizomes are exposed and the roots are spread out, facing downward in the soil. In dry climates the rhizomes may be lightly covered. Firm the soil around the rhizome, then water well. If your irises have long leaves, cut them back to about 6 inches. Because they are shallow-rooted, the heavy tops can pull them over.

Newly set plants need water to help their root systems become established. Deep watering at long intervals is better than more frequent, shallow watering. Once established, iris normally don’t need much water. In hot, dry areas, mulching between rows or between plants helps to conserve moisture. Be careful not to let the mulch get too close to the plant, as the tops of the rhizomes like to bask in the sun.

Keep your iris beds clean and free of weeds and debris. If you mulch your iris, don’t let the mulch cover the rhizomes. Bloom stems should be cut off close to the ground after blooming. During the growing season, healthy green leaves should be left undisturbed, but brown or diseased leaves should be removed. In the late fall, trim off old dying foliage and cut remaining leaves back to about 6 inches.

If you have any gardening questions, please email them to me at cwcasey@shaw.ca