How to Grow Matilija Poppy

Crinkly white flower petals surround a ball-shaped golden yellow center
the delicate crinkly petals of the Matilija Poppy hold up to wind, rain and sun

Sharon Lee / Flickr / CC BY-NC-SA 2.0

In This Article

The Matilija Poppy, also known as the tree poppy, is native to California and northern Mexico. It's scientific name, Romneya coulteri, takes its inspiration from the name of Dr. Thomas Coulter, the botanist who discovered it. This large white flower has six petals with a ball-shaped center of bright yellow stamens. The petals have a wrinkly, crepey, and delicate texture, but they can withstand strong winds and rain. The flower produces abundant nectar and attracts many bees in spring. It's sometimes called fried egg flower, for its uncanny resemblance to a very large fried egg.

Growing between six and nine feet tall, it thrives in dry, sunny climates and can be found among the unique landscape features of southern California such as dry canyons and even in areas that have suffered from wildfires. It goes dormant in winter and is a deciduous summer plant; the leaves usually start drying out and falling in early autumn. It can be grown as an annual in containers or beds in most places, but will only naturalize where it has suitable growing conditions. Once established, it can become invasive, spreading by a network of rhizomes.

A bit of trivia: In 1890 the matilija poppy was a candidate for the state flower of California, but it was beaten in a vote by the California poppy, which although much smaller comes in a large variety of colors.

Botanical Name Romneya coulteri
Common Name Matilija poppy, fried egg plant, California tree poppy
Plant Type Tender perennial 
Mature Size  6 to 10 feet tall 
Sun Exposure  Full sun 
Soil Type  Sandy loam, tolerant of all soils 
Soil pH  5 to 8
Bloom Time  March to August 
Flower Color  White 
Hardiness Zones   USDA 8 to 10
Native Areas  California, northern Mexico
Toxicity  Can cause mild skin irritation 
grouping of tall white poppies with yellow centers with evergreen trees in background
Matilija poppies will spread rapidly in ideal conditions

Sharon Lee / Flickr / CC BY-NC-SA 2.0

Matilija Poppy Care

These majestic plants need a lot of space, so make sure you're able to accommodate them before planting in your garden beds. Their tendency to be invasive is also a consideration; planting in containers might be the best bet. If planting nursery plants, be careful while transplanting to handle the roots gently.

Soil

Being native to dry, arid, desert climates, the matilija poppy prefers dry, sandy soil. It requires good drainage, so clay soils might require amendments. Otherwise this flower is fairly tolerant of diverse soil conditions.

Light

To reach their full height and flowering potential, these plants need full sun exposure. They will grow in dappled shade, but the brilliant golden color of the yellow centers is brightest with full sun exposure.

Water

The best watering practice is to try and mimic native desert watering conditions; that is to say, as if an occasional hearty rainfall occurs every few days. Once a week is reasonable, perhaps every five days or so if growing in containers. It's okay to let the soil dry out a bit between waterings, as this plant is very drought resistant. You'll know to give it supplemental water in addition to your regular schedule when the plant starts drooping. Overwatering will cause leaves to discolor and flower petals to fall prematurely. Mulching to ensure even moisture may also be helpful.

Temperature and Humidity

Matilija poppies thrive in dry conditions and warm temperatures. Their hardiness zone is fairly narrow (USDA 8 to 10), which usually indicates a plant that likes very specific growing conditions. If your growing zone hovers between 7 and 8, you might be able to get these to overwinter by mulching them heavily. If you can mimic the plant's native growing conditions, this may be a plant you can enjoy in your yard. But with the matilija poppy, ideal growing conditions also means the plant can become invasive.

Is the Matilija Poppy Toxic?

The matilija poppy is not harmfully toxic to ingest, but the leaves contain saponins that might cause mild gastric irritation if swallowed. These substances can also mild skin irritation, so it's best to wear gloves when handling the plants.

Common Pests and Diseases

Matilija poppies are deer resistant, drought tolerant, and resistant to most pests, though they can be somewhat susceptible to powdery mildew, which can be treated with neem oil. They might also attract various caterpillars who may munch the eaves and breed; this situation can be controlled by using a Bacillus thurigiensis spray, which is non-toxic to humans.