Species smoothbark St. Johnswort
Smoothbark St. Johnswort (Hypericum lissophloeus) showcasing green leaves and vibrant yellow flowers on reddish stem

smoothbark St. Johnswort

Hypericum lissophloeus

Smoothbark St. Johnswort (Hypericum lissophloeus) is an attractive, evergreen shrub with bright yellow flowers. It grows up to 1.5 meters in height with an almost spherical shape and light green, smooth bark. Its delicate yellow flowers appear in early summer and its dark green leaves have a leathery texture. Its berries are edible and have a juicy, sweet-tart flavor. It prefers moist, well-drained soils and sunny sites and is drought tolerant once established. Smoothbark St. Johnswort is a great choice for low maintenance landscape plantings or incorporated into native shrub mixes.

Cycle:

Perennial

Watering:

Average

Propagation:

Cutting,Layering Propagation,Division,Seed Propagation,Root Cutting

Hardiness Zone:

7 - 9

Flowers:

Yellow Flowers

Sun:

Full sun,part shade

Leaf:

Yes

Growth Rate:

Low

Maintenance:

Moderate

Drought Tolerant:

Yes

Salt Tolerant:

Yes

Invasive:

Yes

Care Level:

Medium

watering

Smoothbark St. Johnswort should be watered regularly, with the amount varying depending on the weather and season. During the warmer months, approximately every 2 to 3 days is ideal, though it is best to check for soil moisture between waterings. In the winter, the amount of watering should be reduced to every 7 to 10 days. When watering, saturate the soil but be careful not to saturate the plant's foliage. Good drainage and aeration of the soil is also important for smoothbark St. Johnswort. In addition, a layer of mulch can help retain moisture in the soil.

sunlight

Smoothbark St. Johnswort (Hypericum lissophloeus) requires full sun for optimal growth. The amount of sunlight for the plant should be in the range of 6 to 8 hours of direct sunlight each day. This can be daily or with some shade in the afternoon. Partial shade is acceptable, however, the plant growth may be slower than in full sun. Because the plant is native to the western United States, it should not be exposed to extreme temperatures or prolonged droughts.

pruning

Smoothbark St. Johnswort (Hypericum lissophloeus) should be pruned during the late winter or early spring when it is not actively growing. Pruning will help to encourage growth and fullness while keeping the plant neat and tidy. Depending on how you want your plant to look, you can either lightly prune, removing only a few of the oldest, leggiest branches, or you can remove more branches to shape the plant or keep it at a manageable size. Be sure to avoid removing more than 25% of the healthy shoots.

Season

Fall
Winter
Spring
Summer
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Starts Flowering

Smoothbark St. Johnswort typically starts flowering in June.

Hardiness Map