Hummingbird Summersweet: How to Grow Hummingbird Summersweet

Hummingbird summersweet, a cultivar of summersweet (Clethra alnifolia), is a deciduous shrub boasting bright green foliage and spikes of fragrant white flowers. Also known as sweet pepperbush, this compact, flowering shrub is deer-resistant and helps attract pollinators to gardens in USDA hardiness zones three to nine. They reach a mature height of three to four feet tall with a three- to four-foot spread.

Peak bloom time for Clethra alnifolia 'Hummingbird' takes place during late summer. Summer blooms are likely to last from July to August. Their showy flowers are most stunning when planted in groupings, mass plantings, or borders. At the end of the growing season, hummingbird summersweet has beautiful fall colors as its green leaves turn to a golden yellow. Other popular summersweet cultivars include ‘Ruby Spice’ and ‘Sixteen Candles.’

Hummingbird summersweet is a shade-tolerant shrub that does exceptionally well in woodland gardens or mixed into perennial borders. It can be planted in growing zones three to nine.

1. 1. Light: Summersweet will tolerate most light conditions, from full sun to partial shade.
2. 2. Soil: Summersweet will tolerate a variety of soil types. It thrives in moist, acidic, sandy soils but will tolerate clay soils as well.
3. 3. Water: Summersweet thrives in moist soils, but overly wet soil will cause the root system to rot. In its first year, water your shrub regularly to help establish the root system. Once established, you can reduce the watering frequency but avoid letting the soil dry out completely.
4. 4. Mulch: Apply a layer of mulch around the base of the plant to help with moisture retention.

Consider these tips for caring for your hummingbird summersweet plants.

1. 1. Pruning: In late winter, after the threat of extreme cold has passed, deadhead blooms and trim back foliage to your desired shape. Pruning will encourage new growth in early spring.
2. 2. Fertilizing: Plants can benefit from an application of organic fertilizer in early spring.
3. 3. Soil pH: Though tolerant of different soil conditions, hummingbird summersweet does best in acidic soil. Check the soil pH if growth is slow and amend it accordingly.
4. 4. Pest control: Hummingbird summersweet is a relatively low-maintenance plant that is not susceptible to many pests or diseases. However, they can occasionally become infested by spider mites. If you suspect an infestation of spider mites, simply spray the plant with water to remove them.

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