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) USDA Zone 9a: to -6.6 °C (20 °F) USDA Zone 9b: to -3.8 °C (25 °F)
Sun Exposure: Full Sun Sun to Partial Shade
Danger: All parts of plant are poisonous if ingested
Bloom Color: Red Scarlet (Dark Red) Orange Bright Yellow
Bloom Time: Mid Spring Late Spring/Early Summer
Foliage: Evergreen Herbaceous
Other details: Average Water Needs; Water regularly; do not overwater This plant is attractive to bees, butterflies and/or birds Flowers are fragrant
Soil pH requirements: 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline) 7.9 to 8.5 (alkaline)
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; 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
On Nov 10, 2010, hawallace from Austin, MN (Zone 4b) wrote:
Started mine indoors early 2009. The plants never got mature enough to blossom. I thought they were only hardy to zone 6, so I was kind of disappointed that they would die over Winter. I left them anyway...and in the Spring 2010, about 2/3 of the plants survived. It took them awhile to perk up, kind of like my herbal sage plants. They had a nice bloom...a lot taller than I thought they would be. I do have the plants in a relatively protected area, so maybe I have a micro-climate. I'm going to try to keep them again, as they are really big and healthy.
Even gardening from 1 zone warmer (zone 6a in Connecticut and Philadelphia) than the given northern limit for this very fragrant flower (zone 5a), Wilson & Bell (The Fragrant Year) eventually gave up growing what we now call Erysimum cheiri outside. That plus the fact that this flower doesn't seem to be grown much outdoors here in zone 7, either, certainly makes me wonder - but then, all the more reason to experiment with wintersowing E. cheiri this winter and again indoors about 2 weeks before last frost (see below) so I can hustle any seedlings outdoors before damping-off fungus rears its fuzzy head. Wilson & Bell say that from North Carolina on south that 6 months of winter bloom can be obtained. Winter gardening must be heavenly down there.
Well, apparently, it is. In A Southern Garden, Elizabeth Lawrence wrote, "There is no excuse for a bare garden in winter, when a packet of seeds from the ten-cent store will make a grey wall gay with yellow, orange and wallflower red. Last winter I drove out of my way nearly every day to pass a yard where...a bed of wallflowers, Cheiranthus cheiri, bloomed at the foot of a stone terrace...they bloomed all through the fall and winter...[always coming back in warm spells following being cut back by a cold spell]..." She was living in Raleigh, NC, at the time.
The books mentioned here are among the best garden books ever written, and I hope readers will try to track them down - even campaign for reprints!
Some germination details are:
1) From B & T World Seeds - "Erysimum cheiri will usually germinate with 10-14 days. Sow seeds about 6 mm (1/4") deep in well drained seed sowing mix at 20*C (68*F)."
2) from Wilson & Bell: "...sow seeds in midsummer...Seeds sprout quickly, and it takes 5 months to bloom. A lean mix of sand, garden soil [sterile soilless seed-starting medium might be better] and ground limestone plus bonemeal keeps plants to window size. We do not bring them until mid-November since they are safe outside as long as sweet alysum blooms...require...cold window..."
On Apr 9, 2005, saya from Heerlen Netherlands (Zone 8b) wrote:
Lovely fragnance and bringing colour in the garden so early in the season. I 've started these from seeds last year and planted them out...stayed wintergreen. All parts of the plant are poisonous..specially the seeds. Plant contains Cheirotoxin that has similar but lesser toxic effects as Digitalis does...
On Jan 17, 2005, LilyLover_UT from Ogden, UT (Zone 5b) wrote:
Wallflowers are nice companion plants for spring bulbs. They bloom all through the daffodil and tulip season. I especially like the dark red blooms of the cultivar 'Blood Red' as they emerge from their black buds.
On Sep 28, 2004, smiln32 from Oklahoma City, OK (Zone 7a) wrote:
Sow seed outside, one fourth inch deep, in June or July. Seed can be sown outdoors up to 2 months before first frost. Seed germinates within a week when grown indoors at temperatures between 55 and 65 degrees. Seedlings are spaced 9 inches apart in the garden. Cuttings may be taken after the plants have bloomed. Most varieties have fragrant flowers. Some winter protection is needed in colder climates. Does not perform well during hot weather.
To grow as annuals,sow outdoors in early spring or indoors about 8 weeks before your last frost date. Plant seed 1/4 inch(6mm)deep. Set plants out 8-12inches(20-30cm)apart around the last frost date. In frost-free areas,grow wallflowers as biennials Sow seed in pots in a nursery bed in early summer;move plants to their flowering position in early fall. Water during dry spells to keep the soil evenly moist. Pull out plants when they have finished blooming.
Cultivars:'Tom Thumb Mixed'blooms in a range of colors on 6-9-inch(15-22.5cm)plants.
This plant has been said to grow in the following regions:
Redding, California Keystone Heights, Florida Boise, Idaho Lewiston, Idaho (2 reports) Mackinaw, Illinois Palatine, Illinois Galena, Indiana Derby, Kansas Millbury, Massachusetts Austin, Minnesota Mathiston, Mississippi Sparks, Nevada Schenectady, New York Woodside, New York Elizabeth City, North Carolina Sanford, North Carolina Austin, Texas Norfolk, Virginia Sammamish, Washington