Maintenance Landscaping Design

Spirea nipponica is a plant that belongs to the family Rosaceae. It is a deciduous shrub that is native to Japan. The plant is also known as bridal wreath spirea or Japanese meadowsweet. The leaves of the plant are ovate in shape and the flowers are white in color. The plant blooms in the summer and the flowers are borne in corymbs. The fruit of the plant is a dark red drupe.

Also known as

• Japanese spirea
  
• Nippon spirea
  
• Wedding cake spirea
  
• Snowmound spirea
  
• Spirea of Japan

Things to Know

• Spirea nipponica is a species of flowering plant in the rose family.
  
• It is native to eastern Asia, in China, Japan, and Korea.
  
• It is a deciduous shrub growing to 1–3 m tall.
  
• The leaves are spirally arranged, 5–10 cm long and 2–4 cm broad, with a toothed margin.
  
• The flowers are white, borne in corymbs 5–10 cm diameter in late spring to early summer.
  
• The fruit is a dry, brown, woody achene.
  
• Spirea nipponica is grown as an ornamental plant in gardens and parks.
  
• It is used as a groundcover or shrub border.
  
• It is tolerant of a wide range of soils and sites.
  
• It is susceptible to powdery mildew and leaf spot.

Related plant:
Spirea Japonica Anthony Waterer

Planting Process

1. For spirea nipponica, first step is to find a young plant that is about 6 inches tall.
   
2. Find an area in your garden that receives full sun to partial shade and has well-drained soil.
   
3. Prepare the planting bed by tilling the soil to a depth of about 8 inches.
   
4. Add some organic matter to the soil such as compost or manure.
   
5. Dig a hole that is twice the width and depth of the spirea nipponica’s root ball.
   
6. Place the root ball in the hole and backfill with soil.
   
7. Water the plant deeply to help settle the soil around the roots.
   
8. Apply a layer of mulch around the base of the plant to help conserve moisture.
   
9. Water the plant regularly, especially during the first growing season.
   
10. Fertilize the plant in early spring with a slow-release fertilizer.

Related plant:
Douglas Spirea

Soil Requirement

About soil condition, Spirea nipponica prefers well-drained soils rich in organic matter. It does not do well in overly wet conditions or soils that are highly alkaline. It is tolerant of a wide range of pH levels, from 4.5 to 8.0.

Light condition

Similar to other spirea shrubs, the Japan spirea (Spirea nipponica) requires full sun to produce an abundant display of flowers. In partial sun, it will still bloom, but the flowers will be fewer and the shrub may become somewhat leggy. This deciduous shrub is a good choice for foundation plantings, hedges and mass plantings. It grows in USDA hardiness zones 4 through 8.

The Temperature

The temperature condition for spirea nipponica is that it should be planted in an area that receives full sun to partial shade. It is tolerant of a wide range of temperatures, but it prefers a cool climate. It can withstand temperatures as low as -30 degrees Fahrenheit.

Humidity Requirement

Ideal humidity condition for this plant is around 40-50%. If the humidity gets lower than that, the leaves will start to curl and the plant will become less vigorous. If the humidity gets too high, the leaves will start to yellow and the plant will become more susceptible to fungal diseases.

Fertilizing

Discussing fertilizer, usually the plant food we see in stores is a mix of Nitrogen, Phosphorus, and Potassium or what is called NPK for short. These are the macro-nutrients that plants need in large quantities. However, there are other nutrients needed in smaller quantities that are just as important. These are called micro-nutrients and include things such as iron, manganese, copper, zinc, and molybdenum. Most of the time, the soil contains enough of these nutrients for plant growth, but sometimes they need to be added. The roots of spirea nipponica are very delicate and need to be taken care of properly in order to ensure the best possible growth for the plant. One way to do this is to make sure that the roots have access to the proper nutrients. This means using a fertilizer that is high in NPK and also contains the necessary micro-nutrients. By doing this, you will be giving the plant the best chance to grow and thrive.

Plant Pruning

Pruning spirea nipponica helps to ensure that the plant remains healthy and looking its best. This shrub can be pruned in early spring or late fall. When pruning, be sure to remove any dead or damaged branches. It is also important to thin out the plant to allow air and light to reach the inner branches.

The Propagation

Propagation : Spirea nipponica can be easily propagated from stem cuttings taken from new growth in late spring or early summer. Cuttings should be taken from healthy, disease-free plants and should be about 6-8 inches long. Cuttings can be rooted in a mixture of sand and peat or a commercial potting mix. Rooting hormone may be applied to the base of the cutting to encourage root development. Cuttings should be placed in a bright, indirectly lit location and kept moist but not wet. Once roots have developed and new growth has begun, the rooted cuttings can be transplanted into individual pots or into the garden.

Growth Speed

Usually, the plant growth rate is fast, with a moderate to high growth rate. The plant can attain a height of 15 feet (5 meters) and a width of 10 feet (3 meters). In urban areas and other locations where the plant is subject to drought or frost, the growth rate may be somewhat slower.

Basic Problems

Common problems for this kind of plant are pests, diseases, and malnutrition. Pests include aphids, scale insects, whiteflies, and spider mites. These pests can cause the leaves to yellow and drop off the plant. Diseases include powdery mildew, rust, and bacterial leaf spot. These diseases can cause the leaves to turn brown and fall off the plant. Malnutrition can cause the leaves to turn yellow and fall off the plant.

Basics of Growing

• Remember to keep the plant well hydrated – water regularly and deeply.
  
• Place the plant in an area with bright, indirect sunlight.
  
• Keep the soil moist but not soggy – allow the top few inches of soil to dry out in between watering.
  
• Fertilize during the growing season – use a balanced fertilizer.
  
• Prune as needed to shape the plant and encourage new growth.
  
• Keep an eye out for pests and diseases – treat as needed.
  
• Deadhead spent flowers to prolong blooming.
  
• Divide the plant every few years to keep it healthy and vigorous.
  
• Remember to mulch around the base of the plant to help retain moisture.
  
• Enjoy your beautiful spirea nipponica plant!

You May Like

• Spirea alba
  
• Spirea angustifolia
  
• Spirea aruncus
  
• Spirea betulifolia
  
• Spirea brunnea
  
• Spirea callosa
  
• Spirea cantoniensis
  
• Spirea cinerea
  
• Spirea decumbens
  
• Spirea divaricata

Source:
Snowmound Spiraea - Spiraea nipponica 'Snowmound' | North …
Snowmound Nippon Spirea (Spiraea nipponica 'Snowmound')
Managing Pests in Gardens: Trees and Shrubs: Spirea—UC IPM - ucanr.edu