Sun is a significant component of the successful growth of most plants. While most plants prefer full sun, some thrive in partial to shaded areas. Such plants include the iris.
Iris has about 300 different species growing in hardy zone 3-11 hence other growing conditions. These plants have beautiful blooms that cover your garden in the spring, early summer and even during early fall.
Therefore, it would be better to understand the type of irises before you decide on the right one for your garden with the difference in growing conditions. Learn more about irises in this article.
Some irises like the Iris foetidissima or stinking iris would thrive under a tree or on the north side of the house where there’s little to no light access. Its name comes from the unpleasant aroma it produces after cutting or bruising its leaves. Growing the stinking iris is the best way to add life and color to the shaded woodland parts. It is also an easy-to-grow ground cover.
It’s beautiful, and pale lilac flowers can grow in the 18-24 inches during the spring. It also has seedpods that open during the fall season revealing orange seeds that look like beads. If you are an art fan person, you can use the dried seed stalks for flower arrangements.
The stinking iris grows in USDA zone 6-9 and prefers warmer climates to keep their leaves green even though shade tolerant. Cold climate or winter seasons will affect this iris to death.
Irises that prefer full sun can tolerate some shade as well. They like dry to boggy soil conditions though this will vary with different species.
The popular bearded iris (Iris germanica) has sword-shaped leaves. This iris thrives in full sun or a minimum of 6 hours of sun daily. A majority of bearded iris grow up to 28” tall buts its dwarf kind the ‘BumbleBee’ growing about 10-17 inches tall.
The original bearded iris has several types of breeds growing from it due to difference in nature and plant breeders. This variety results in diverse colors and cultivars. The German iris grows in USDA zone 3-9.
Also, the Dutch iris is popular and a sun-loving hybrid among the Dutch growers. This iris features strong stems, 4 inch wide flowers, grey-green leaves and a height of 1-2 feet. The Dutch iris thrives in USDA 6-9.
The Japan iris is a native of East Asia and cultivated in Japan also loves full sun to partial shade. It comes with flat ruffled flowers, sword-shaped leaves and grows to 24 inches tall. The Japan iris prefers moist soil though do not overwater to avoid root rot. You can pot the Japan iris but ensure you maintain wet conditions but change to drier conditions during the winter season. This iris performs well in hardy zones 4-9 with constantly moist soil.
Your first choice of the iris should be the Siberian iris since it’s straightforward to grow in a home garden. The Siberian thrives in sunny and shaded conditions; however, a prolonged shady stay will negatively affect their growth. Leaving them in a shaded location for a long time will result in the plant’s weak growth and stunted flowering. This iris prefers clay soils due to the wet and moist conditions and selects USDA zone 3-8.
Moreover, the Virginia iris performs best in averagely wet soil conditions hardy zone 5-9. It grows to about 1-3 inches tall with broad leaves. Preferably, plant it in a pond about 6 inches deep or an ever moist flowerbed. It prefers both full sun and partial shade in warmer regions.
How to Grow Iris in a Garden
The irises have different planting conditions since they come in two groups; bulbs and rhizomes. Iris prefers acidic, loose and well-drained soil. The best time to plant or divide the iris is in late summer for the bulbs or rhizomes to have enough time to develop before winter. When producing the iris;
- Work loose the soil and add 2-4 inches of compost in the ground.
- Dig a hole twice bigger than the rhizome about 4-5 inches deep.
- Remove excess soil in the centre and then burrow the rhizome into the hole.
- Make sure the roots stretch out away from the rhizome.
- Cover the rhizome with the excavated soil.
- Leave about 1/3 of the rhizome exposed to the sun or leave it uncovered if the weather is sweltering.
- Ensure you water your iris thoroughly after planting and avoid mulching.
For the iris bulbs, plant in the depth of 2-3 times the bulb size during late fall. Plant with the pointed end up in compost amended soil. Also, water the iris thoroughly after covering.
How to Divide the Iris
To avoid overcrowding or growing into unwanted location, divide your iris after every 2-3 years. The best time should be after summer when the blooming season is over.
- Dig your iris up carefully not to harm the roots and rhizome in the ground.
- Remove all the debris or dirt from the bulbs or rhizomes and place it on a flat and stable surface.
- Using a sharp knife, separate the rhizomes or bulbs. Make sure each part has enough roots so that it regrows without any strain.
- Make sure you cut out and dispose of the decaying or dead parts.
- Wash the divided rhizomes and bulbs carefully and gently while inspecting any pests and diseases.
- If you have a loved one interested, you can share some of the split rhizomes. Otherwise, replant them in the areas you would love a ground cover.
How to Care For Your Iris
- Irises are easy to maintain but require constantly moist soil conditions. Ensure your water always whenever the soil is dry to touch to avoid overwatering.
- Fertilize the iris using a slow-release fertilizer specifically for iris bulbs and rhizomes. For re-blooming iris, fertilize a second time after the first spring blooming is through.
- Deadhead the spent blooms often to retain energy and give room for fresh blooms. Do this by cutting the entire flower stalks after blooming and be careful not to cut the foliage.
- Monitor your iris for any form of pests like iris borers and diseases. They cause dark, watery vertical lines on the leaves that need you to cut and dispose immediately they appear. To prevent the iris borers, remove all the debris from the rhizomes after the first frost. This way, you will remove the eggs before they hatch to attack and cause rhizome rot.
Every home deserves some natural color from ornamental plants. Hence, Irises are perennial plants that have beautiful blooms of different colors and sizes. They will do well under your trees or in the bare garden; therefore, you cannot miss a favourable spot to grow them. Also, they are not common in many homes as many people don’t know about them. Stand out from the rest of the crowd in a different iris way.