North America Non-native Plant

Lemonyellow Iris

Botanical name: Iris flavescens

USDA symbol: IRFL2

Life cycle: perennial

Habit: forb

Native status: Non-native, reproduces and persists in the wild in the lower 48 states  

Lemonyellow Iris: An Uncommon Non-Native Perennial If you’ve stumbled across the name lemonyellow iris in your plant research, you might be wondering what exactly this mysterious perennial is all about. The lemonyellow iris (Iris flavescens) is a bit of an enigma in the gardening world – a non-native species that ...

Lemonyellow Iris: An Uncommon Non-Native Perennial

If you’ve stumbled across the name lemonyellow iris in your plant research, you might be wondering what exactly this mysterious perennial is all about. The lemonyellow iris (Iris flavescens) is a bit of an enigma in the gardening world – a non-native species that has quietly established itself in a few scattered locations across the United States.

What is Lemonyellow Iris?

Iris flavescens is a perennial forb, which is just a fancy way of saying it’s a non-woody herbaceous plant that comes back year after year. Like other members of the iris family, it lacks the significant woody tissue that you’d find in shrubs or trees, instead growing fresh stems each season from underground structures.

This species has earned its place as a naturalized resident in parts of the American landscape, meaning it reproduces on its own in the wild without human intervention and has established persistent populations.

Where You’ll Find It

The lemonyellow iris has made itself at home in just three states: Illinois, Kentucky, and Pennsylvania. Its limited distribution suggests this isn’t exactly a widespread garden favorite, which might explain why detailed growing information is surprisingly scarce.

Should You Grow Lemonyellow Iris?

Here’s where things get a bit tricky. While Iris flavescens isn’t listed as invasive or particularly problematic, its non-native status and limited cultivation information make it a questionable choice for most gardeners. The lack of readily available growing guides, seed sources, or cultivation tips suggests this species isn’t commonly grown in home landscapes.

Consider Native Alternatives Instead

If you’re drawn to the idea of iris flowers in your garden, why not consider some fantastic native options that will better support your local ecosystem? Here are some wonderful alternatives:

  • Blue Flag Iris (Iris versicolor) – A stunning native with purple-blue flowers
  • Southern Blue Flag (Iris virginica) – Perfect for wet areas with lovely blue blooms
  • Wild Iris (Iris brevicaulis) – A shorter native species with charming blue flowers
  • Rocky Mountain Iris (Iris missouriensis) – Great for western gardens

The Mystery Factor

One of the most intriguing things about Iris flavescens is how little information exists about its cultivation requirements, pollinator relationships, or specific garden uses. This lack of documentation might indicate that it’s either rarely cultivated or perhaps not particularly noteworthy from a horticultural standpoint.

Bottom Line

While the lemonyellow iris isn’t going to harm your garden if you somehow manage to acquire it, there are so many better-documented, more readily available native iris species that would be superior choices for most gardeners. These native alternatives will provide guaranteed beauty, established growing information, and the added bonus of supporting local wildlife and pollinators.

Sometimes in gardening, the most mysterious plants are mysterious for good reason – they’re simply not the best choice for our home landscapes. In this case, you’re probably better off exploring the wonderful world of native irises that are eager to thrive in American gardens.

Lemonyellow Iris

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Liliidae

Order

Liliales

Family

Iridaceae Juss. - Iris family

Genus

Iris L. - iris

Species

Iris flavescens Delile - lemonyellow iris

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA