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Hardiness: USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
Sun Exposure: Light Shade Partial to Full Shade
Danger: Parts of plant are poisonous if ingested
Bloom Color: Bright Yellow
Bloom Time: Mid Spring Late Spring/Early Summer
Foliage: Grown for foliage Herbaceous Silver/Gray Blue-Green Bronze-Green
Other details: Average Water Needs; Water regularly; do not overwater
Soil pH requirements: 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline)
Patent Information: Non-patented
Propagation Methods: By dividing rhizomes, tubers, corms or bulbs (including offsets) From seed; direct sow outdoors in fall From seed; sow indoors before last frost From seed; direct sow after last frost
Seed Collecting: Allow pods to dry on plant; break open to collect seeds Properly cleaned, seed can be successfully stored
On May 10, 2013, sallyg from Anne Arundel,, MD (Zone 7a) wrote:
For two years it has lived in my partly shaded bed of natives, and looked beautiful. So far it does not seem to self sow much here. (C. lutea can self sow a lot here). I was trying to collect seeds today and found that tiny ants were in among the seed pods, and each carrying a seed away.
On Jan 2, 2009, SunnyBorders from Aurora, ON (Zone 5a) wrote:
I planted one Corydalis cheilanthifolia plant, about 4 or 5 years ago, in my garden (zone 5A) in a relatively shaded and moist location, but soon felt it seeded around too much. The plants are easy to remove, but I have been pulling up C. cheilanthifolia offspring of that one plant ever since.
I have, over numbers of years, used Corydalis lutea (also yellow flowered) for relatively shaded areas. The foliage may not be quite as attractive as that of C. cheilanthifolia, but C. lutea has a phenomenally long bloom time (May to September). It certainly also seeds around, especially with moisture, but the plant with its fleshy root is extremely easy to pull up.
I also have spring flowering purple Corydalis solida in the same location. It's spread has been quite minimal compared to that of C. lutea, but it was pointed out to me that because C. solida grows from a corm (and not a fleshy root), C. solida plants could be difficult to get rid of.
I was given some white (and yellow lipped) Corydalis ochroleuca in Victoria, Vancouver Island (zone 8b), this June 2008. The spread and ease with which an excess of it could be removed, in the garden in Victoria, really brought our C. lutea to mind. I am hoping that winter does not take it upon itself to remove the new C. ochroleuca from my garden!
On May 6, 2002, lupinelover from Grove City, OH (Zone 6a) wrote:
The leaves on this plant change color through the year. Newly emerging leaves are bronze, change to green, then become silver-green in the fall. Flower stalks grow on separate stems from the leaves, and they are held slightly higher than the leaves. Flowers are yellow, tubular, and attractive to bees and ants.
Everyone who has seen this plant in my garden wants it.
Seed very easy to collect. Allow the pods to dry before harvesting. Ripe seed is black, unripe seed is white, making it easy to distinguish. Each flower forms a seed pod, with 20-30 seeds per pod. Does not require cold stratification to germinate.
As with many corydalis, this does not transplant well. The best way is to grow it from seed directly sown where it is to grow. It accepts transplanting if grown in cell packs, but may take an extra year or two to fully establish.