Victoria County Master         Gardener Association

Caryopteris x clandonensis

'DARK KNIGHT'

It has ominous botanical name, but is great plant

September 25, 2020

by Charlie Neumeyer/Victoria County Master Gardener

Edited by Charla Borchers Leon/Victoria County Master Gardener

PHOTO CONTRIBUTED BY VICTORIA COUNTY MASTER GARDENER CHARLIE NEUMEYER

This young Bluebeard was planted about a month ago in Master Gardener Charlie Neumeyer's garden.  Young plants as shown here have an upright shape which will spread as the plant ages.

PHOTO CONTRIBUTED BY VICTORIA COUNTY MASTER GARDENER CHARLIE NEUMEYER

This photo shows the size of a mature Caryopteris x clandonensis 'Dark Knight'.  This plant has been in the ground for eight to ten years and is planted with Gulf Muhly Grass.  In the fall, the pink grass heads with the Bluebeard in the foreground in this setting is very attractive.

PHOTO CONTRIBUTED BY VICTORIA COUNTY MASTER GARDENER CHARLIE NEUMEYER

The flowers of the Caryopteris x clandonensis 'Dark Knight' are very attractive for pollinators.  Butterflies, bees and wasps have been buzzing around the plant all summer long.

OTHER CULTIVARS THAN 'DARK KNIGHT' OF

Caryopteris x clandonensis

• 'Hint of Gold' - Golden Foliage
• 'Sterling Silver'- Silver Foliage
• 'Summer Sorbet' - Gold/Green Variegated Foliage

ALL BLUE TO BLUE/LAVENDER FLOWERS

• 'Longwood Blue'
• 'Heavenly Blue'

TWO PINK CULTIVARS

• 'Pink Perfection'
• 'Pink Chablis'

CULTIVATION

• Well-drained soil
• Full sun
•  Moderate water
•  Prune, fertilize in spring

POSITIVE ATTRIBUTES OF CARYOPTERIS

• Deer resistant
•  Compact growth habit
•  Bee and butterfly attractor
•  Disease resistant
•  Moderate to low water

PHOTO CONTRIBUTED BY VICTORIA COUNTY MASTER GARDENER CHARLIE NEUMEYER

This is a close-up of the Caryopteris x candonensis 'Dark Knight' flower.  Notice the large number of buds beneath the open flowers.  Each cluster blooms for several weeks and there are multiple clusters on each branch.

When I visit nurseries, especially locally owned businesses, I’m always on the lookout for unusual (at least for me) plants. I’ve found Anacacho Orchid Trees in Smithville, Mexican Olive Trees in Rockport and Sunshine Ligustrum in Victoria. Several years ago, I was checking out a nursery in San Antonio and came across Caryopteris x clandonensis 'Dark Knight' or Bluebeard.

I had never seen this plant before, and I continued walking around the nursery but ended up back at the plant knowing that I was going to buy it. And, of course, I did.

Although Caryopteris x clandonensis ‘Dark Knight’ is sometimes labeled as a “native” plant, it originated in China. According to Wikipedia, the cultivars that are currently being sold are the result of an accidental cross-breeding between a Caryopteris incana and a Caryopteris mongholica. Some other names for the plant are Bluebeard and Blue Mist Spirea.


One of the 'Dark Knights' growing in my garden has been there for about 10 years. It normally blooms in late summer to fall, but this year it has bloomed continuously from early spring. The only difference of which I am aware is that I fertilized it this year.

This perennial grows to about 3 feet high and across. The blooms are borne on long, supple stems and the clusters are both terminal and axillary. The 'Dark Knight' flowers are blue to purple-blue and are in clusters with 20 to 30 buds in each cluster and 16 to 18 clusters on each bud stem. The leaves are gray-green and smell faintly of eucalyptus.

The 'Dark Knight' has many characteristics that make it desirable. It is a perennial and stays low growing. I have only pruned it in the spring if it has frozen back. According to “The Plant Hunter,” the shrub flowers on new growth, so if it needs pruning, just do so in the spring. The plant base limbs are quite stiff and woody, so prune after the new growth has begun.

According to “The Spruce,” the 'Dark Knight' is a major pollinator attracter. I’ve seen butterflies, wasps, bumblebees and honey bees on my bush. If you are working around it, be on the lookout for yellow jackets. They really like to build nests in the base limbs. I have had no problems with any type of diseases or debilitating insects.


The 'Dark Knight' is generally care-free and easy to grow. According to “Dave’s Garden” site, the plant needs well-drained soil. If you have soil that retains water, the plant will develop root rot. You will have to modify the soil or plant the Caryopteris in large pots. They need full sun. While some sites said that they can be used in a xeriscape garden, I have found that my plants do better with regular watering. The plants can be grown from Zone 5 to Zone 9.

I talked with two wholesale nurseries about Caryopteris propagation and both said they used stem cuttings. According to “The Spruce” website, the cutting should be about 6 inches long and should be soft wood from new growth. You should remove the bottom leaves and dip the cuttings in rooting hormone then plant them in a potting mix. The cuttings need bright, indirect light and should be well-watered until a good root system has developed.

The site also indicated that the plants will naturally come up from seed and that they could be transplanted. Some sites said the plant can be invasive because it seeded so freely. I have never had a plant come up from seed and the nurserymen said that they would not consider the plant to be invasive.


However, according to “Horticulture,” a gardening magazine, the seeds must be chilled for three months and that is highly unlikely to occur naturally around here.

As I wrote earlier, these plants are somewhat difficult to find. According to the wholesale nurserymen, the bluebeard has gone “out of style” and is considered old-fashioned. I found some recently in San Antonio, but did not find any locally. Several on-line sites do offer them for sale. The wholesale nursery in the Dallas area said that they are fairly popular up there, but not near to being a best seller.

Should you buy it?

Yes, I definitely think it is a worthwhile plant. It adds lots of color in late summer when other plants have stopped blooming. It is low maintenance, pest free and deer resistant.

The Gardeners’ Dirt is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas A&M AgriLife Extension – Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, TX 77901; or vcmga@vicad.com, or comment on this column at VictoriaAdvocate.com.