How to Grow And Care For Japanese Pieris

Last Updated on November 28, 2022 by Plant Mom Care

Japanese Pieris, an evergreen broadleaf shrub from the heath family, is indigenous to Asia and adds beauty to gardens and landscapes. The leaves are ovoid, opening in reddish-bronze before changing to glossy green. 

It grows about 9 – 12 feet high, 6 – 8 feet in diameter, and flowers early, producing drooping clusters of white or pink flowers in late winter/early spring for around two weeks. Several cultivars differ in flower color, hardiness, and size, including compact varieties that can be cultivated in containers. 

This upright or spreading ornamental grows slowly and takes time to get established in your garden or landscape and is ideally planted as borders or foundations together with other plants or shrubs. 

Japanese Pieris Light Requirements

In cooler areas, these plants prefer growing in full sunlight, getting a minimum of 6 – 8 hours every day; however in warmer areas it does better under the partial shade with protection to shield it from the harsh afternoon sun. 

Gardeners in the southern US states often consider this plant to be a lover of shade, but it does require morning sun to flower properly and afternoon shade to prevent the foliage from scorching.

Japanese Pieris Watering

These plants need constant watering once weekly. While they prefer moist soil, they cannot tolerate water-logged soil. 

Japanese Pieris Humidity

They grow well in dry to moderately humid settings, although very hot and humid conditions can bring fungal diseases like leaf spots. Plant them apart and prune them regularly to enable good air circulation.

Japanese Pieris Temperature

They grow well in temperatures of 65 – 75°F and thrive in zones 4 to 8. Protect the plants from very cold or harsh winds, which can bring on leaf browning or make the foliage die back.

Japanese Pieris Soil

They grow well in soil rich with organic matter, stay moist, drains well, and have an acidic pH. They struggle in soggy soil and are vulnerable to root rot if the soil is water-logged. 

Japanese Pieris Repotting

This plant is best repotted every 2 – 4 years in spring or when roots appear from the drainage holes. First, remove the plant and inspect the roots, removing dead or damaged roots. After this, place the plant back into the original container or a new slightly larger container with good drainage capacity. Fill up the empty spaces and thoroughly water the plant. 

Japanese Pieris Propagation

This plant can be propagated from cuttings or seeds.

Propagation from cuttings take 6- or 8-inch cuttings from vigorously growing stems in summer. Remove the lower leaves on the cuttings, then scrape the bark off the last 2 inches and dip the scraped ends in the rooting hormone. 

Plant the cuttings in small containers filled with moistened potting mix. Place the pots in an area protected from direct sun with temperatures between 65 – 75°F. Keep watering when the mix becomes dry. Rooting will take 6 – 8 weeks. Keep the saplings in their pots until late autumn, then transplant them in the garden/landscape or larger containers.

Propagation From Seed. While this is not commonly done, this plant can be propagated from seeds collected from mature seed pods in late autumn. Plant the seeds during the following summer in your garden or containers, barely covering the seeds with soil. 

Keep watering regularly until the seeds start germinating, usually in 2 – 4 weeks. Protect the new seedlings from direct sun. If you start the seeds in containers, they can be transferred to the garden in late autumn but make sure you harden the seedlings before transplanting them into your garden.

Japanese Pieris Additional Care

Use a fertilizer specifically formulated for camellias, azaleas, and rhododendrons in the middle of February and May, following the instructions. 

Regular deadheading of spent flowers will prevent the plant from producing seeds and encourage continuous flowering. Additional pruning is unnecessary, as the plant grows quite attractive naturally. If the plant is failing or becomes affected by fungal disease, pruning might be needed every few years. 

Start by removing diseased or damaged branches, cutting about ½ inch from a leaf bud then, cut off stems at the top to your desired height. Next, cut off about ¼ from the inner stems to create space in the center for light and air. Complete pruning by shaping the plant to your desired shape.

Japanese Pieris Common Problems

Common pests attacking these plants include mites, lace bugs, and nematodes. Treat any pest infestations by spraying the foliage with insecticidal soap or neem oil solutions.

These plants can be prone to several fungal diseases like phytophthora root rot and leaf spot which spread very easily in humid or water-logged conditions. Proper spacing between plants is essential for good air circulation. 

Keep around 6 to 7 feet between plants, keeping in mind how they will spread when mature. Severe root rot might be fatal, resulting in death.

Sometimes, if the plant is planted too deep, it might not flower. It must be replanted at the identical depth as the nursery container. If this happens, dig it up and replant it with the root ball slightly higher.

Cold temperatures in winter or spring might kill flower buds sometimes. The plant will usually return to its normal flowering the next season. Over-fertilization often causes excessive foliar growth and fewer flowers; it takes a year or two for the plant to return to normal flowering after overfeeding. 

If it stops flowering after you feed it, stop feeding completely. Resort to top-dressing the soil with compost instead when flowering resumes.

Insufficient light can also cause poor flowering. While it needs shade from intense sunlight, it still requires sufficient light to flower. Plant it where it will receive morning sun and shaded afternoons in hot climates. 

Yellow leaves are often a result of chlorosis caused by alkaline soil. This plant prefers an acidic pH. If this happens, try adding an acidifying fertilizer, or amend the soil with pine needles.

Leaf wilt and sagging stems are sometimes diagnosed as under-watering. In truth, this usually suggests that the plant is overwatered and might be infected by phytophthora fungus. If this happens, water the plant only when the topsoil is dry.

The plant has likely been overexposed to direct sun if leaf edges become brown and branch tips begin to wither. This is common in warm climates and the plants need some shade during the hot hours of the afternoon.