Clethra alnifolia
TAXONOMY
FamilyClethraceae
GenusClethra
Zone4
LEARN MORE
Plants of the World OnlineABOUT
Clethra alnifolia, commonly known as Sweet Pepperbush or Summersweet, is a deciduous shrub native to the eastern United States. It thrives in temperate climates and is known for its fragrant white or pink flowers that bloom in late summer. The plant goes dormant in winter, shedding its leaves.
ALSO KNOWN AS
Sweet Pepperbush
Clethra alnifolia f. alnifolia
Clethra alnifolia f. paniculata
Clethra alnifolia f. rosea
Clethra alnifolia var. alnifolia
Clethra alnifolia var. denudata
Clethra alnifolia var. glabella
Clethra alnifolia var. paniculata
Clethra alnifolia var. pubescens
Clethra angustifolia
Clethra bracteata
Clethra dentata
Clethra incana
Clethra paniculata
Clethra pubescens
Clethra pumila
OVERVIEW
VPDCalculate
WaterWet
SoilLoamy
LightIndirect Bright (6 Hours)
Temperature20° C
Humidity60%
Dormancy3 Months
pH5.5
Pressure1,013 mbar
DETAILS
Care Instructions
Clethra alnifolia prefers moderate temperatures and indirect bright light. It thrives in evenly moist soil and benefits from regular watering, especially during dry periods. The plant enjoys moderate humidity and should be protected from extreme heat and cold.Soil
This shrub prefers loamy soil that is well-draining yet retains moisture. It can tolerate a range of soil types but performs best in slightly acidic to neutral pH levels. Ensure the soil remains consistently moist but not waterlogged.Fertilizer
Use a balanced fertilizer with an N-P-K ratio of 10-10-10. Fertilize in early spring and again in mid-summer to support healthy growth and flowering. Avoid over-fertilizing as it can lead to excessive foliage growth at the expense of flowers.Repotting
Repotting is generally not necessary for outdoor shrubs, but if grown in containers, repot every 2-3 years. Choose a slightly larger pot with good drainage and refresh the soil mix to provide new nutrients.Propagation
Clethra alnifolia can be propagated through softwood cuttings taken in late spring or early summer. Dip the cuttings in rooting hormone and plant them in a well-draining soil mix. Keep the cuttings moist and in indirect light until roots develop.Pruning
Prune Clethra alnifolia in late winter or early spring before new growth begins. Remove any dead or damaged branches and shape the shrub to maintain its form. Light pruning after flowering can also help encourage bushier growth.Toxicity
Clethra alnifolia is not toxic to pets or humans. It is a safe choice for gardens where children and animals are present.Additional
Clethra alnifolia is a great addition to gardens for its late summer blooms and pleasant fragrance. It attracts pollinators like bees and butterflies, making it beneficial for the ecosystem. Mulching around the base can help retain soil moisture and regulate temperature.REVOLUTIONIZE YOUR PLANT CARE
Make Every Plant Smart
Plant Monitor
STAYS IN YOUR PLANT
Accurately measures the core metrics of your plant – soil moisture, light, temperature and humidity - as well as compound metrics such as Vapor Pressure Deficit (VPD) and Growing Degree Days (GDD).
Shop Now
