How to Grow Spiraea - Plant Care & Tips

By NorwichGardener Team / 2024

Spiraea is a plant that is mainly found in china and japan. it is a deciduous shrub that can grow up to 2 meters tall. the spiraea plant has small, white flowers that bloom in the springtime. this plant is sometimes used as an ornamental plant in gardens.

Also known as

Bridalwreath spiraea
Vanhoutte spiraea
Meadow spiraea
Hardhack spiraea
Japanese spiraea

Good to Know

Spiraea is a genus of about 80-100 species of flowering plants in the rose family.
Most species are native to the temperate Northern Hemisphere, with a few in the Southern Hemisphere.
They are shrubs ranging in height from 10 cm to 4 m.
The leaves are spirally arranged, simple, and usually have toothed margins.
The flowers are borne in corymbs or panicles, and have five petals, which are sometimes fused at the base.
The fruit is usually a dry, winged capsule.
Spiraea are widely cultivated as ornamental plants, and some species are used in traditional medicine.
Some species of Spiraea are grown for their edible fruits, which can be used in pies, jams, or other dishes.
Spiraea are susceptible to a number of diseases, including powdery mildew, leaf spot, and stem canker.
Spiraea are also susceptible to attack by a number of pests, including aphids, scale insects, and caterpillars.

Related plant:
Spiraea Grefsheim

Growing Steps

For spiraea, first step is to find a location that has well-drained soil and receives full sun.
Next, dig a hole that is twice the width and depth of the plants root ball.
Once the hole is dug, place the plant in the hole so that the top of its root ball is level with the surrounding soil.
Backfill the hole with soil, tamping it down as you go.
Water the plant deeply immediately after planting.
For the first few weeks, water spiraea plants regularly, giving them about 1 inch of water per week.
Once established, spiraea plants are quite drought tolerant and only need supplemental watering during extended periods of dry weather.
Fertilize spiraea plants once a year in early spring with a balanced fertilizer.
To encourage bushier growth, prune spiraea plants back by one-third their height in late winter or early spring.
Finally, spiraea plants are generally disease and pest free. However, aphids and spider mites can occasionally be a problem.

Soil Condition

About soil condition, the Spiraea prefers well-drained soils with a moderate amount of moisture. It is tolerant of a wide range of soils, including heavy clay. The roots are shallow, so the plant needs a consistent supply of water during drought conditions.

Light requirement

Just like other plants, Spiraea need sunlight to grow properly. At least six hours of sunlight a day is ideal, but the plant can tolerate partial shade. If the plant doesn't get enough sun, it will become leggy and produce fewer flowers.

Ideal Temperature

The temperature condition for spiraea is that it requires full sun and prefers cooler temperatures. It can tolerate some shade but will not flower as profusely. Spiraea does best in moist, well-drained soils but is tolerant of dry soils once established. It is a low maintenance plant that is relatively pest and disease free.

Humidity Aspect

Ideal humidity condition for this plant is between 40 to 50%. If the humidity level is too low, the leaves will start to curl and the plant will become drought stressed. If the humidity level is too high, the leaves will start to yellow and the plant will become susceptible to fungal diseases.

Fertilizing

Mentioning fertilizer, usually the plant that first comes to mind is grass. Though commonly used on lawns, grass is not the only plant that benefits from fertilizer. Many flower beds contain ornamentals that respond well to an annual feeding. One such plant is spiraea. Spiraea is a hardy shrub that is easy to care for. It has a long blooming season and comes in a variety of colors. Though it is a tough plant, it does respond well to fertilizer. A good way to determine when to fertilize is to wait until the plant starts to show signs of new growth. This is usually in late spring or early summer. When applying fertilizer, be sure to use one that is specifically made for shrubs. Also, be sure to water the plant after applying the fertilizer. This will help the roots to absorb the nutrients.

About light

Pruning your spiraea is an important part of keeping it healthy and looking its best. It is best to prune in late winter or early spring, before new growth begins. You can prune spiraea to remove any dead or damaged branches, to control its size, or to shape it. When pruning, be sure to use clean, sharp pruning tools to avoid damaging the plant.

About Propagating

Propagation is best done in early spring by seed, or by softwood or hardwood cuttings. If you are collecting your own seed, be sure to only collect it from plants that have not been treated with chemicals. Start your seedlings in a cold frame or protected area, as they are slow to germinate and grow. Once they are large enough to transplant, harden them off for a week or two before planting them in their permanent spot in the garden. To take cuttings, look for new growth that is still soft, and cut just below a leaf node. Strip the lower leaves off the cutting, and dip the end into rooting hormone. Stick the cuttings into a well-draining potting mix, and keep the soil moist but not wet. Place the pot in a protected area out of direct sunlight, and in a few weeks you should see new growth.

Plant Growth

Usually, the plant growth rate quickly in full sun with moist, well-drained soil. However, some varieties are quite tolerant of different growing conditions. Most will tolerate some shade and some of clay soil. Depending on the type, spiraea can be either deciduous or evergreen.

The Problems

Common problems for this kind of plant plants are generally fungal problems such as powdery mildew, rust, or leaf spot. These can be controlled with fungicide sprays. Borers can also be a problem, particularly the spiraea clearwing borer. Borers are difficult to control and the best management strategy is to remove and destroy infested branches.

Growing Tips

Make sure to choose a site with full sun and well-drained soil.
Prepare the planting bed by tilling or digging to a depth of about 8 inches.
Gently remove the plant from its container and loosen any tightly wound roots.
Place the plant in the prepared bed and backfill with soil, tamping down lightly as you go.
Water the plant deeply and thoroughly immediately after planting.
spiraea are generally low-maintenance plants, but they will benefit from occasional fertilization. Use a balanced fertilizer applied according to package directions.
Prune spiraea plants as needed to shape them and encourage new growth.
Be on the lookout for common pests such as aphids, scale, and Japanese beetles. These can be controlled with insecticidal soap or other organic pest control methods.
Powdery mildew can be a problem in humid climates. Treat with a