There’s no mystery in why irises are the showy crown jewel of many people’s gardens. Their beautiful, fan-shaped petals delicately drape against flashy green foliage. Although many of us picture the iconic blue, indigo, and yellow foliage of a classic iris, the name “Iris” is actually from the Greek word for rainbow, a testament to just how much variety can be found in these plants. With so many colors and such phenomenal foliage and blooms, there is a statement-making iris for anyone.
Growing Irises: What are Tubers?
Irises grow a little different than many of the other plants in your garden. While you can technically grow them from seed like other flowers, the most recommended and direct way to get irises for your garden is from bulbs.
Irises grow from rhizomes, a horizontal stem that is rounded and swollen underground. Many gardeners are familiar with tubers in foods that they eat, like potatoes, or yams. Irises emerge by shooting roots and stems from a tuber.
Planting Iris Tubers
Irises prefer lots of sunshine to fuel their dainty, show-stopping blooms, so they are best planted in mid or late summer in a spot that receives lots of sun in a day. At least half a day of full, hot sun is important for them to grow and look their best. Plant each tuber about 12” apart so that each bloom has the space that it needs for good air circulation. The more sun and air it gets, the more it will shine in your garden.
Take special care to protect Iris rhizomes from moisture and rot to have a successful showing of these blooms. Choose well-draining soil or amend yours with sand to make sure that the roots don’t sit in water, which can damage them.
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Steps to Plant Irises
- Check your tuber to make sure that it is healthy. Avoid signs of rot like soft pots, smell, or a hollow feeling. It’s disappointing to put the effort into growing a beautiful Iris to only have a crop of nothing.
- Dig a wide and shallow hole (about 10” wide and 4” deep) in well-draining soil
- Set the tuber in the hole on its side, with the roots facing downwards. Fan out the roots around the tuber.
- Fill in the hole, but leave the top of the tuber slightly exposed so that it has access to the sun and air it needs to stay dry.
- Water thoroughly after planting, but afterwards only water occasionally to avoid rot.
- Don’t mulch, but consider sprinkling some low-nitrogen fertilizer on top.
With a bit of patience and regular upkeep, you’ll have a gorgeous bloom that is ready to impress!
Caring for Irises
If you take the time to be meticulous about planting the tuber, the care for a growing iris is actually very simple. Water lightly and keep them exposed to lots of sunshine and these plants do all of the heavy lifting for you.
Blooming irises are a blessing in your landscape, with complex and delicate blooms that catch the eye. Appreciate them in your garden or cut them and bring them inside—these gorgeous flowers are a treat that commands your attention no matter where you place them.
At the end of the season when the blooming is done, resist the urge to trim and clean them up right away. Leaving the foliage intact allows the plant to continue to gather sun and get the nutrition it needs to survive the winter and bloom again in the spring. You can cut the flowering stem right down to the tuber if you want, but leave the leaves as long as you can – you’re investing in your future Irises!
Tubers might be a little strange and intimidating when you’re first working with them, but they actually have the same needs that most of your garden plants do. Provided you care for the tubers properly, you’ll soon enjoy these magnificent flowers all summer long.