Hardiness: USDA Zone 3a: to -39.9 °C (-40 °F) USDA Zone 3b: to -37.2 °C (-35 °F) USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) 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) USDA Zone 9a: to -6.6 °C (20 °F) USDA Zone 9b: to -3.8 °C (25 °F) USDA Zone 10a: to -1.1 °C (30 °F) USDA Zone 10b: to 1.7 °C (35 °F) USDA Zone 11: above 4.5 °C (40 °F)
Other details: Requires consistently moist soil; do not let dry out between waterings
Soil pH requirements: 5.6 to 6.0 (acidic) 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral)
Patent Information: Non-patented
Propagation Methods: From seed; direct sow outdoors in fall From seed; winter sow in vented containers, coldframe or unheated greenhouse From seed; stratify if sowing indoors From seed; direct sow after last frost
On May 8, 2013, Marches from Chester United Kingdom wrote:
Self seeds in woodlands and rocky areas in Western England, Wales and Western France. It's a lovely shade of yellow in most cases, but I have seen orange ones.
Puts up with cooler conditions well, thrives in damp, shady areas of woodland and half way up wooded mountain sides. Would probably suit the Pacific North West, Norway, Iceland, Faroe Islands, Falkland Islands and West coast region of New Zealand well.
On May 11, 2009, anelson77 from Seattle, WA wrote:
These grow in sun to deep shade and reseed heavily. The seedlings do pop up all over, but are easy to pull. It looks good most of the year, with pretty blue green foliage. It really lights up the shade in spring and early summer.
On Nov 4, 2005, SoTired from Peck, ID (Zone 6b) wrote:
This plant blooms in the tough Southeast Alaska climate (very cool summers and lots of rain) from spring until fall. It grows here in full sun to shade. It reseeds like crazy, so be sure you want it. For a semi-wild spot, where you want color all season with no fuss, it works great.
On Sep 6, 2003, pleb from Plymouth, United Kingdom (Zone 9a) wrote:
The Welsh Poppy can be frequently found in the shady, moist hedgebanks of Devon where the summers are often cool and moist. Best to keep it out of your garden here (unless you have a wild garden) because it can be hard to get rid off. It seeds itself and regrows from its fleshy roots if you hoe its top off.
This is a very successful plant (12+ years) in my Zone 8 yard in Olympia WA (about 70 miles south of Seattle). Blooms from early spring through the first hard frosts. Nice clear yellow flower. It reseeds VERY freely in shade and semi-shade. Pest-free and somewhat drought-tolerant. We've had a gruesome summer (from a plant's viewpoint-and mine) with many 90+ degree days and no measurable rain for nearly 2.5 months. It seldom rains in the summer here anyway, but the temps are not usually so high for such a long time. A very welcome sight in early spring - it thrives on spring rain and cool temps, but also grows well in the hostile conditions described above.