How to Grow Caryopteris Kew Blue - Plant Care & Tips

By NorwichGardener Team   /   2024

Caryopteris kew blue is a plant that is native to China and Japan. It is a member of the mint family and has blue flowers that bloom in the summer. The plant grows to be about two feet tall and prefers to grow in full sun.

How to Grow Caryopteris Kew Blue - Plant Care & Tips

Popular name

  • Beardtongue
  • Cat's Whiskers
  • Feverfew
  • Yarrow
  • Bluebeard

Basic info

  • Caryopteris Kew Blue is a deciduous shrub that is native to China.
  • It is a member of the family Caprifoliaceae.
  • The shrub typically grows to a height of 3-4 m (8-11 ft).
  • The leaves are ovate to oblong-ovate in shape and measure 7-14 cm (8-5 in) long by 3-7 cm (2-8 in) wide.
  • The leaves are blue-green in color with a toothed margin.
  • The flowers are blue in color and appear in summer.
  • The fruit is a small, black drupe.
  • The shrub is commonly used as an ornamental plant in gardens.
  • It is also used in traditional Chinese medicine.
  • Caryopteris Kew Blue is considered to be an invasive species in some parts of the world.

Related plant:
Caryopteris X Clandonensis

Planting Process

  1. For caryopteris kew blue, first step is to plant the seeds in pots or trays filled with moistened potting mix or seed starter mix.
  2. Place the pots in a warm, sunny location and keep the soil moist.
  3. Once the seeds have germinated, transplant the seedlings into larger pots filled with a well-draining potting mix.
  4. Place the pots in a sunny location and water regularly, keeping the soil moist but not soggy.
  5. Fertilize the plants monthly with a balanced fertilizer.
  6. When the plants are large enough, pinch back the tips to encourage bushiness.
  7. In late summer or early fall, cut back the plants by one-third to one-half to encourage new growth.
  8. Bring the pots indoors before the first frost, and place them in a sunny location.
  9. Reduce watering during the winter months, but do not allow the soil to dry out completely.
  10. Resume monthly fertilization in the spring, and cut back the plants again in late summer or early fall.

Related plant:
Caryopteris Blue Mist

Considering the Soil

About soil condition, Caryopteris Kew blue prefers slightly acidic to neutral soil that is moist but well-drained. If the soil becomes too dry, the leaves may start to curl and the plant may become stressed. To avoid this, water regularly and deeply, especially during hot, dry weather. Amend the soil with compost or other organic matter to help retain moisture.

Light condition

So, like the other plants, caryopteris kew blue needs sun to live. Without sun, the plant will eventually die. It is important to make sure that the plant gets at least six hours of sunlight each day. If the plant does not get enough sun, it will become weak and unhealthy.

Ideal Temperature

The temperature condition for Caryopteris Kew Blue is warm. This means that it can tolerate temperatures as low as 50 degrees Fahrenheit. However, it will thrive in temperatures that are between 60 and 80 degrees Fahrenheit.

Humidity Level

Ideal humidity condition for this plant is 50% and above. This plant cannot tolerate low humidity conditions and will start to drop leaves if the humidity level is below 50%. If the humidity level is too high, the plant will start to get leaf fungus.

Fertilizer Requirement

The fertilizer, usually the plant food, that you will use for your caryopteris kew blue should be based on the recommendation of a soil test. A well-balanced fertilizer, such as 10-10-10, or one with a slightly higher nitrogen content, such as 12-12-12, is best. If you use a fertilizer with a high nitrogen content, such as 30-10-10, you will encourage excessive leaf growth at the expense of flower production. Apply the fertilizer when you plant the caryopteris kew blue and again in early spring, before new growth begins. Scratch it into the surface of the soil around the plant, taking care not to get any on the plant itself. Water the fertilizer in well.

About light

Pruning is an important part of keeping your Caryopteris Kew Blue healthy and looking its best. This shrub can be pruned in late winter or early spring, before new growth begins. You can prune to shape the shrub or to remove any dead or damaged branches.

About Propagating

Propagation for Caryopteris Kew Blue is typically done through softwood cuttings taken from new growth in the spring or early summer. The cuttings should be about 4-6 inches in length and taken from healthy, new growth that has not yet flowered. Cuttings should be taken from the tips of the stems, as this is where the most actively growing tissue is. After taking the cuttings, remove the bottom leaves and dip the cut end in hormone rooting powder. The cuttings can then be planted in a well-draining rooting medium. Be sure to keep the cuttings moist, but not wet, and in a location with bright, indirect light. Cuttings should root within 4-6 weeks.

Growth Rate

Usually, the plant growth rate is slow to moderate depending on the species. However, some are known to grow quite rapidly. They are generally deciduous shrubs, although a few are evergreen. They range in size from 2 to 6 feet tall and wide. Most have blue or purple flowers that appear in late summer or early fall.

The Problems

Common problems for this kind of plant include powdery mildew, downy mildew, stem rot, root rot, and leaf spot. These problems can be caused by too much or too little water, over-fertilizing, or poor drainage. To help prevent these problems, water your caryopteris kew blue regularly and evenly, fertilize it sparingly, and make sure it has good drainage.

Tips on Growing

  • Do not forget to water your caryopteris kew blue plant regularly.
  • Place your plant in a sunny spot.
  • Feed your plant with a high-quality fertilizer.
  • Prune your plant regularly to encourage new growth.
  • Keep an eye out for pests and diseases.
  • Provide your plant with well-drained soil.
  • Mulch your plant to help retain moisture.
  • Stake your plant if it becomes too tall.
  • Deadhead spent flowers to encourage reblooming.
  • Enjoy your beautiful caryopteris kew blue plant!



Caryopteris, or Bluebeard, is outstanding in gardens
Species: Caryopteris x clandonensis - Cornell University
Bluebeard (Caryopteris x clandonensis)-Hort Answers

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Reviewed & Published by Richelle
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Shrubs Category