Iris is both beautiful and elegant, and luckily it is also easy to grow given the simply stunning blooming it offers.
Here is the care and small acts of care that will sustain the beautiful blooming of your iris from year to year.
A summary of Iris facts
Type: bulbous flower or perennial
Height: 8 to 36 inches (20 to 90 cm)
Exposure: full sun, part sun
Flowering: January to July depending on the variety
The best period for planting iris is spring or summer, usually from May to November for the plants to bloom in the following summer.
- Plant the iris rhizomes in soil that has been well broken up, without burying them too deep.
- Keep a minimum spacing of 2 to 4 inches (5 to 10 cm) between each iris plant.
- Let the iris rhizomes stick out here and there for the sun to shine on them directly.
- This will keep them from rotting, which they would do if buried too deep.
- For a nice decorative impact, sow about 15 plants to a square yard (1 m²).
Iris is especially vulnerable to lack of sun that would keep it from blooming correctly, and its second nemesis is waterlogged soil.
If sowing from seed, better sow your iris in pots in September-October.
- You can leave them outdoors, under some type of shelter, all winter long.
- Blooming will only occur 2 to 3 years after the sowing.
- You’ll proceed to transplant them directly in the ground as soon as the first leaves have sprouted.
Iris is a plant that very easily propagates through division.
As years go by, rhizomes tend to crowd tighter and tighter, the soil loses its nutrients and the iris blooms are weaker and weaker.
That is the right time to divide your iris so that the rhizomes get to breathe a bit and their vigor is renewed.
The technique to propagate iris is actually rhizome division after the blooming every 3 to 4 years.
- This division is performed in summer, when the blooming is less abundant or has even petered out.
- Division may also be performed in fall.
- With a spading fork, carefully unearth a portion of the rhizomes, lifting them out of the ground.
- With knife at this point, separate the rhizomes and keep larger pieces, each about 4 inches (10 cm) long.
- Replant these rhizome shards in another spot of the garden, or offer some to your friends.
- During the planting, cover with a good layer of soil and add time-release fertilizer, also adding some to the original rhizome location.
This step gives the plant a new life, and it will joyfully get to work making new flowers for you for free!
Trimming and caring for Iris
Caring for iris can really become only the occasional check, because this is a flower that requires very little work.
Apart from dividing the rhizomes as described above, here are the practices that will help extend the blooming or simply increase the quality of the iris flowers.
- Remove wilted flowers as they die off, but keep the leaves until the very end of their yellowing, usually until September.
Iris leaves must be kept connected to the roots for the plant to build up its stocks for the following blooming.
- Remove weeds that grow amidst the plant leaves to free the rhizomes.
- No need to water because the plant doesn’t need it.
Watering and adding fertilizer for iris
Iris resists dry spells particularly well and will only need to be watered in case of very high temperatures and/or extended dry spell.
However, potted iris will need much more regular watering, usually when the substrate has dried up deep down.
- Provide granulated time-release flower plant fertilizer in spring.
Diseases and parasites attacking iris
Iris is quite invulnerable to disease but it may fall victim to snails and slugs.
All there is to know about iris
Three magnificent petals form the flower, and their colors are most varied.
Often in tones of purple, they can also be blue, yellow, red or white.
The lifespan of an iris can reach anywhere from 5 to 20 years and its hardiness and resistance to the cold can reach down to 5°F (-15°C).
Over 200 species of iris have been accounted for, and each has a unique color and shape combination.
Note that certain iris species are used to produce perfume, with oils extracted from the rhizome.
Meet an Iris aficionado
Here are the tips of Jean-Claude Jacob, who developed and produces Iris. He’ll tell us about the ‘Lame de Fond’ iris variety.