Pseudofumaria lutea [syn. Corydalis lutea (kore-ID-uh-liss, LOO-tee-uh)] is a short-lived perennial belonging to the poppy family, Papaveraceae and previously known sub-family Fumariaceae.
Native to the Alps of Italy and Switzerland, the plant has now been naturalized in other parts of the world.
The genus name comes from a Greek word, korydalis.
This word means crested lark, which is a nod to the plant’s resemblance to the lark’s head.
Common names are much simpler including:
- Corydalis
- Yellow Corydalis
- Fumewort
- Fumitory
- Rock Fumewort
The plant is known for its showy yellow flowers, which combine well with peonies, bleeding hearts, and lungwort or pulmonaria.
Corydalis Lutea Care
Size & Growth
The plant is an aggressive grower as it self-seeds, almost bordering being weedy in some areas where the growing conditions are optimal.
The bright to light green, ferny foliage may remind you of maidenhair ferns.
The fern-like leaves on the plant form neat mounds, which can reach a height of 15” inches and an approximately 18”-inch wide spread.
The leaves are finely divided, 2-3 pinnate with 3-lobed leaflets that look very similar to bleeding heart (Dicentra).
Flowering and Fragrance
The showy flowers on the yellow corydalis are is the crowning glory.
Each tubular flower is 2 centimeter or 0.75” inch long.
The bright to golden yellow flowers are borne on in racemes on short and branched leafy stems and are 4-petaled.
The top petal has a sounded spur, the inner 2 are connected to the tip, and both bottom and top petals are crested.
The average bloom time is May through September.
It lasts from early summer to late summer and throughout early fall.
In some regions, the plants can flower from the last frost to early spring or even late spring.
This species produces bright completely yellow blooms, unlike the Corydalis ochroleuca species which produces yellow-white striped blooms.
Light & Temperature
When all other growing conditions are met completely, light shade or part shade is optimal but the plants will thrive under full shade.
The plant can tolerate full sun but the green foliage may scorch, especially if moisture is lacking.
Hollowort plants are hardy to USDA Hardiness Zones 4 through 8.
The Corydalis can survive successfully in cool summer climates.
Hot weather is usually not tolerated well; the foliage scorches and is generally intolerant of humid and hot summers.
Watering and Feeding
The plant does best in moist soil. To ensure it does, water regularly and do not allow the soil to dry out completely between watering.
Corydalis goes into dormancy in the winter, lowering their water needs.
Reduce the frequency of watering as wet soils in the cold season are fatal to the plant.
During spring, before the flower buds bloom, feed the plants with a shovelful of organic compost.
If compost is not available, use a gentle, organic fertilizer formula.
Soil & Transplanting
Wet or moist soil conditions and partial shade locations are extremely beneficial to Corydalis.
- The soils should also be rich and well-drained.
- Add gravel and pebbles to a heavier soil mix to improve its drainage.
- The plant doesn’t respond well to transplanting.
- Transplant the new seedlings to new locations after the plants have self-seeded.
Grooming and Maintenance
These plants are very low-maintenance and do not need the foliage pruned.
Deadhead to remove spent flowers to prevent pro-longed self-seeding.
How to Propagate Yellow Corydalis
Propagate ‘Yellow Fumitory’ by seed or by diving rhizomes, tubers, corms or bulbs.
- Purchased Corydalis seeds can have erratic germination.
- Collect fresh seeds and plant them in the fall, allowing them to germinate through spring.
- Divide the plants in early fall once the flowers have faded or in spring.
Yellow Corydalis Pest or Diseases
C. lutea is virtually free of serious pest and disease problems.
There might be a problem with downy mildew, rust, aphids, slugs or snails.
Fortunately, these pest and disease problems are easily treatable.
Visit your local gardening center to find non-toxic solutions.
Toxicity
The plant is toxic to horses.
If ingested, they can cause gingivitis, mouth sores, and even sudden death.
Keep away from pastures and fields where horses might graze.
Uses For Bright Yellow Corydalis
Use this plant to enhance shade gardens, rock gardens, and border fronts.
When planted with daylilies, yellow corydalis looks spectacular in cottage gardens.
More on Daylily Care – The What When and How
Plant them in stone wall pockets if you have a cool summer climate.
Another option is to plant them between other plants in shady woodlands to form a nice ground cover.