We proudly research, grow, and write about our plants by hand. Descriptions are based on our experience as well as information gathered from reputable sources: books, periodicals, and select websites. Should you have questions beyond what is listed please email or call.

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Close-up of purple Iris tectorum, commonl known as roof iris, flowers with green leaves in the background
Purple Iris tectorum, commonly known as roof iris,  flowers with green leaves in a garden setting
White Iris tectorum, commonly known as roof iris, flower with yellow centers surrounded by green leaves
Blue Iris tectorum, commonly known as roof iris,  flower with green leaves in the background

Iris tectorum | roof iris

Regular price
$8.99
Regular price
Sale price
$8.99
Shipping calculated at checkout.

Grown from seed in living soil without the use of pesticides, chemicals, or carbon fuels.

All in stock plants will ship FALL 2026.


Roof iris (Iris tectorum) is a beautiful, evergreen, spring-blooming Iris from the crested iris group. It received the common name 'roof iris' as it was once widely planted on thatched roofs in Japan and China. Today, it is most commonly grown as a rapidly spreading perennial in the garden. It is happiest when planted on consistently moist but well-drained soil in full sun or part shade. 

Zones: 4 to 9 
FamilyIridaceae
Type: Herbaceous perennial
Height: 12 to 18 in.
Spread: 12 to 18 in.
Exposure: full sun to part shade
Soil: average, fertile, moist, well-drained
Bloom Time: May
Native Range: Central and southwestern China, Myanmar

J2-a

Special Characteristics
  • Deer-resistant
  • Drought resistant
image credits
White Iris tectorum, commonly known as roof iris, flower with yellow centers surrounded by green leaves
Close-up of purple Iris tectorum, commonl known as roof iris, flowers with green leaves in the background
Purple Iris tectorum, commonly known as roof iris,  flowers with green leaves in a garden setting
Blue Iris tectorum, commonly known as roof iris,  flower with green leaves in the background

Ordering information

Preorders

You may place your order anytime to reserve plants for fall 2026 shipping. If you place multiple orders, we will combine plants into one box (or as many as needed) and any extra shipping charges will be refunded.

We will resume shipping as soon as temperatures cool in our location and yours. This can range from the beginning of September for northern locations to the end of October for hot locations (Texas). 

We will check in with you a week before shipping to make sure you receive your plants at a time that is convenient for you.

Shipping

Live plants ship in spring and fall only. Plants may ship dormant, depending on variety and season. Shipping costs are most reasonable when bundling like size plants.

  • 4-inch: 1-6 plants ship for $15.00 / 7-13 plants ship for $18.00 / 14-30 plants ship for $40.00
  • 1-gal: 1-2 plants ship for $18.00 / 3-4 plants ship for $25.00 / 5-6 plants ship for $40.00
  • trees & shrubs: $27.00-$40.00 each, height dependent
  • seeds: $6.75 or free with orders over $15.00

We regret that we cannot ship internationally or to the following states: AK, AZ, CA, CO, FL, HI, ID, MT, NV, OR, UT, or WA.

Read more about our shipping policies here.

Nursery pick up

We will email you to schedule a day and time to collect your plants when they are ready in spring. Generally, plants can be collected from the nursery Monday through Sunday from 10am-4pm in Spring, Summer, and Fall.

Plant Sizes

We most commonly use the following pot sizes for perennials:

  • 4-inch pot: 3.5" H x 3.5" W x 3.5" D
  • 2-quart pot: 6" H x 5.25" W x 5.25" D
  • 1-gallon pot: 6.87" H x 8" Dia (this is a true one gallon pot, not the smaller 'trade' one gallon pot used by many nurseries)

Check out our illustrated pot size guide here.

Representative trees & shrubs are photographed in their pots and posted on each plant page.

Sustainability

Sustainability is at the heart of what we do at The Old Dairy. We grow all of our plants outdoors without the use of chemicals, fertilizers, carbon fuels, or peat.

Many of our perennials are grown in the ground and dug upon order (this is especially true for larger sizes). This practice allows us to grow stronger, healthier plants using native soil, and ultimately reduces our impact on the environment.

Our open-pollinated seeds are collected from plants in our mother beds, which have never been treated with chemicals or sprays of any kind.

Read all about our sustainable practices here.

Iris tectorum seedlings in four-inch black potsIris tectorum seedlings in four-inch black pots

view this plant in our garden

Iris tectorum | roof iris |

seedling image

Iris tectorum | roof iris

We are slowly creating a seedling image library to help make weeding easier.