There are around 300 varieties of iris flowers in the Iris genus. These famous flowers come in two main forms: those that grow from rhizomes and those that grow from bulbs. They are characterized by unique flowers that consist of two different types of petals: petals and petals. The waterfalls form the lower petals that hang or fall downwards. The standards are the top three petals of the flower.
The characteristics of an iris petal further divide the plant into three types: bearded, crested, and beardless. Bearded irises have soft hairs on their hairs that resemble a beard. The flowers of a crested iris have a comb-like ridge on their bases. Beardless people have neither hair nor a comb.
Irises that grow from bulbs include Iris reticulata, Spanish (Iris xiphium) and Dutch varieties (Iris x hollandica) and bloom earlier than the rhizomatous irises. However, most irises show their famous flowers in early summer, and some also bloom a second time in late summer. They are known for attracting butterflies and hummingbirds and make excellent cut flowers. The size of the iris varies greatly, from the smallest dwarf variety, which grows just 15 cm tall, to the tallest variety, which grows up to 1.20 m tall.
Different types of irises require slightly different planting methods and timing. Bulb irises, which include Dutch irises, Spanish irises and Reticulata irises, are planted in full sun in fall in well-drained soil.
To plant your bulbs, loosen the soil and then mix in compost and 1/4 cup of all-purpose granular fertilizer according to the instructions on the bag. Place the bulbs 4 to 5 inches deep, depending on the bulb type. For irises, position the rhizomes horizontally in the soil, leaving the top of the rhizome partially exposed. For other varieties, position the crown of the plant 1/2 to 1 inch below the soil line.
Once the flowers have faded, cut off the flowers. When the entire flower stalk is consumed, cut it down to the ground to direct energy to the roots instead of forming seed heads. Once the first hard frost comes or your leaves turn yellow for the season, you can cut the leaves of your iris down to the ground to prevent iris borers from overwintering in the leaves. However, do not try to remove the foliage beforehand, as the greenery is still photosynthesizing and providing the plant with the energy it needs to bloom next year.
Once the foliage is cut back for the winter, be sure to cover the rhizomes with something to protect them, such as sand or mulch. Remove these in spring. Irises are a good choice for areas with wildlife because they are deer resistant. Common pests are iris borers.
Most iris varieties grow best in full sun. Some varieties tolerate partial shade, but too much shade will prevent flowering.
Nutrient-rich, well-drained soil is best suited for iris plants. Although they like moist soil, too much water can be harmful. If you are concerned about too much standing water, try planting your irises in raised beds as this allows for optimal water drainage. Japanese irises and Louisiana irises tolerate moist soil and are great for areas near ponds. Siberian irises prefer acidic, moist soils.
Since irises like both moisture and well-drained soil, consistent and thorough watering is very important. Just be careful not to overwater, as too much water in the soil can cause problems like root rot. Although they appreciate consistent water, most iris species are drought resistant and will not die easily if deprived of water for short periods of time.
Temperature and humidity
With its wide variety of varieties and growing zones, the iris is a hardy plant that can tolerate fluctuations in temperature and humidity. As long as the soil is well-drained and they get plenty of water and sunshine, these flowers can thrive in a variety of gardens. Siberian irises, irises and Japanese irises are typically hardy in USDA zones 3-9; Iris reticulata and Dutch iris are hardy in zones 5-9; and Louisiana iris prefers zones 6-9.