How to Grow Spirea Douglasii - Plant Care & Tips

By NorwichGardener Team   /   2024

Spirea douglasii is a species of flowering plant in the rose family. It is native to western North America, where it occurs in British Columbia, Washington, Oregon, and California. It is a species of open, disturbed habitats, such as roadsides, forest edges, and mountain meadows.

How to Grow Spirea Douglasii - Plant Care & Tips

Alternative name

  • Hardhack
  • Rose Spirea
  • Steeplebush
  • Bog Rosemary
  • Meadowsweet

Basic info

  • Spirea douglasii, also known as hardhack or Douglas' spirea, is a species of flowering plant in the rose family.
  • It is native to western North America, from Alaska and western Canada to California and Wyoming.
  • It is a perennial herbaceous plant growing to 1–2 m (3–6 ft) tall.
  • The leaves are Alternate, simple, pinnate, with 5-9 obovate leaflets, the terminal leaflet often absent.
  • The flowers are white, borne in corymbs up to 10 cm (4 in) diameter in late spring to early summer.
  • The fruit is a dry brownish achene.
  • The species is named for Scottish botanist David Douglas.
  • It is a popular landscaping plant in many parts of North America.
  • It is sometimes called "brideweed" due to its use in weddings.
  • It is considered a weed in some parts of the world.

Related plant:
Spirea Japonica Anthony Waterer

How to Grow

  1. For spirea douglasii, first step is to choose theright location. The plant prefers full sun to partial shade, and well-drained soil.
  2. Next, prepare the planting hole. It should be twice as wide and just as deep as the root ball.
  3. Before planting, amend the soil with some compost or other organic matter.
  4. To plant, set the root ball at the same level it was in the pot. Gently backfill the hole, tamping down as you go.
  5. Water the plant deeply and regularly during the first growing season.
  6. Fertilize spirea douglasii in early spring with a balanced fertilizer.
  7. To keep the plant looking tidy, prune it back in early spring.
  8. Spirea douglasii is generally pest and disease free. However, watch for powdery mildew, leaf spots, and aphids.
  9. The plant does best in USDA hardiness zones 4-
  10. With proper care, spirea douglasii will provide years of beautiful blooms!

Related plant:
Spirea Japonica Little Princess

Soil Condition

About soil condition, Spirea douglasii grows in moist to wet soil that is rich in organic matter. It does best in full sun, but it can tolerant some shade. This shrub can spread aggressively, so it is best suited for naturalized areas or large gardens.

About light

Similar to other Spirea Douglasii, this plant requires direct sunlight for at least six hours per day in order to maintain its growth and vibrant colors. If you live in an area with limited sunlight, you may find that your plant grows more slowly or doesn't produce as many flowers. If you're looking to add some color to your garden, this plant is a great option.

Good Temperature

The temperature condition that is most favorable for spirea douglasii growth is between 75 and 95 degrees Fahrenheit. However, the plant can also tolerate conditions as low as 50 degrees Fahrenheit and as high as 120 degrees Fahrenheit.

Humidity Level

Ideal humidity condition for this plant is 50%. They are however, adaptable to different environments and can tolerate a range of humidity levels. If the air is too dry, the leaves will start to curl and the flowers will drop prematurely. If the air is too wet, the leaves will start to yellow and the plant will be more susceptible to fungal diseases.

The Fertilizer

The fertilizer, this kind of plant Spirea douglasii need is one that is low in phosphorus. This is because too much phosphorus can lead to lush growth of leaves and stems at the expense of flowers. If you decide to use a fertilizer that contains phosphorus, apply it to the soil around the base of the plant, taking care not to get any on the leaves. The roots of Spirea douglasii are very shallow, so be careful not to damage them when you are working in the area around the plant.

Light requirement

Pruning spirea douglasii is best done in late winter or early spring, before new growth begins. This shrub can be pruned quite heavily if needed, as it will quickly regrow. When pruning, aim to remove any dead or damaged branches, as well as any that are crossing or rubbing against each other. You can also thin out the shrub to promote air circulation and help prevent disease.

Plant Propagation

Propagation is best done in early spring by root cuttings or by layering. Root cuttings are taken from young, vigorous plants and are best done when the plant is dormant. Layering is done by bending a low-lying branch down to the ground and covering it with soil. The branch will root where it touches the ground and can be severed from the parent plant once it is well rooted.

Growth Speed

Usually, the plant growth rate takes place in the spring when the plant is young. The plant can grow quite rapidly,up to 2 feet per year. Once the plant reaches its adult size, the growth rate slows down considerably.

The Problems

Common problems for this kind of plant are aphids and rusts. Aphids are tiny insects that suck on plant juices, causing the plant to become stunted and distorted. Rusts are fungal diseases that cause orange or brown spots on the leaves. Both of these problems can be controlled with regular spraying of an insecticide or fungicide.

List to Know

  • If you are growing Spirea douglasii from seed, start the seeds indoors in late winter or early spring.
  • Sow the seeds on the surface of a mix of perlite and peat moss.
  • Keep the seedlings moist but not wet and place them in a bright location.
  • When the seedlings are large enough to handle, transplant them into individual pots.
  • Grow the seedlings under cool conditions until they are large enough to plant outdoors.
  • Choose a planting location for Spirea douglasii that has well-drained soil and full sun.
  • Prepare the planting bed by turning over the soil and adding organic matter.
  • Set the plants in the bed, spacing them 18 inches apart.
  • Water the plants well and mulch around them with straw or bark chips.
  • Keep an eye out for aphids, which can be

Similar Plants

  • Spirea
  • Spirea alba
  • Spirea arguta
  • Spirea betulifolia
  • Spirea callosa
  • Spirea coronaria
  • Spirea cuspidata
  • Spirea davurica
  • Spirea filipendula
  • Spirea juglandifolia

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Reviewed & Published by Richelle
Submitted by our contributor
Herbs Category