Hardiness: 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: Full Sun
Bloom Color: Blue-Violet
Bloom Time: Mid Summer Late Summer/Early Fall
Foliage: Deciduous Blue-Green Aromatic
Other details: This plant is attractive to bees, butterflies and/or birds Self-sows freely; deadhead if you do not want volunteer seedlings next season This plant is resistant to deer
Soil pH requirements: 6.1 to 6.5 (mildly acidic) 6.6 to 7.5 (neutral) 7.6 to 7.8 (mildly alkaline)
Propagation Methods: From woody stem cuttings From softwood cuttings From semi-hardwood cuttings From hardwood cuttings 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 By simple layering By air layering
Seed Collecting: Allow pods to dry on plant; break open to collect seeds Allow seedheads to dry on plants; remove and collect seeds Properly cleaned, seed can be successfully stored
On Mar 11, 2013, Clary from Lewisburg, PA (Zone 6b) wrote:
As another comment from PA has noted, the blue spirea in my area (including mine) are thin and die back before summer is over. A few gardeners (including me) have cut them back to the ground to see what will become of them next year. Mine is in a rose garden with no lack of fertilizer and water. I suspect that the increasingly scorching heat here in PA is killing them.
On Jun 24, 2012, Sandwichkatexan from Copperas Cove, TX wrote:
So very happy with this plant ! I love how it has filled in the large blank space between my salvia greggii furmans red . It looks beautiful ! The butterflies seem to love its flowers. in the afternoon heat it seems to move because it has so many butterflies on it . I also love the silvery color of the foliage . I purchased this on impulse just to fill in a space I had no idea it was going to be so beautiful and look like it was meant to be there the whole time !
On May 27, 2009, karenathurston from Philadelphia, PA wrote:
I live in zone 6a and planted a 'Longwood Blue' 2 years ago. It flowered the first year but there were no flowers at all last year. The foliage is also not as dense as the majority of photographs I have come across. It gets full sun from noontime until sunset in a fairly dry area that I substitute water during the hotter summer months. I'm going to try fertilizing it this summer to see if that helps it improve - it's looking kind of scraggly.
On Apr 27, 2009, leelynne from Dover, PA (Zone 6a) wrote:
I have 3 of these shrubs and I love them. I got them last year and they sprang up so fast I couldn't believe it. This year I bought a new home and just had to take my chances in transplanting them. So far they are doing well. Since I transplanted them they've actually gotten more leaves on them. I did prune them after I transplanted them since I heard that it's best to prune in the spring to encourage blooming.
On Jan 15, 2009, catcollins from West Friendship, MD (Zone 6b) wrote:
I planted a Longwood Blue in middle of the backyard and a Worchester Gold out front by the street. I have lots of "volunteers" popping up, but only in the front yard for some reason, and only along the driveway. These do seem to be a cross, paler leaves then Longwood, but also with the "blue" tinge. Very pretty. I've tried to transplant these volunteers without success - too much gravel to extract them from. These little guys bloom their first fall and do their part to attract honey bees and butterflies by the hundreds. I do wish they would pick better spots to take up house....
I cut mine back in winter to encourage fuller growth.
On Mar 17, 2007, berrygirl from Braselton, GA (Zone 7b) wrote:
Caryopteris clandonensis 'Longwood Blue' BLUE MIST SHRUB Dec (z5) (Cut,Hon,Bfly)
Chosen at Longwood Gardens in PA for its heavy crop of heavenly-blue flowers & silver foliage on tidy upright pls, 18-24"tall; provides a bright splash of l.summer blue for border, foundation, or low hedge. Sun/Med
This plant has been said to grow in the following regions:
, (2 reports) Chino Valley, Arizona Tucson, Arizona Grand View Estates, Colorado Dewey Beach, Delaware Cloverly, Maryland Olney, Maryland Thurmont, Maryland West Friendship, Maryland Topsfield, Massachusetts Belleville, Michigan Pennsauken, New Jersey Croton-on-hudson, New York Elizabeth City, North Carolina Geneva, Ohio Twinsburg, Ohio Ashley, Pennsylvania Butler, Pennsylvania Dover, Pennsylvania Philadelphia, Pennsylvania Tiverton, Rhode Island Knoxville, Tennessee Copperas Cove, Texas Lowry Crossing, Texas Roman Forest, Texas San Angelo, Texas Temple, Texas Provo, Utah Arlington, Virginia Linden, Virginia Seattle, Washington West Richland, Washington