Gardeners deemed Rehmannia elata to be "Chinese Foxgloves" because the tubular flowers bear a resemblance to Digitalis, the foxgloves plant. The two plants, however, are actually unrelated. With Chinese foxgloves, spikes of dangling, bell-shaped, rose-pink blossoms poke up from scalloped, glossy green leaves. Unlike traditional foxgloves, however, Chinese foxglove petals of the bell lip flare open and outward.
|Botanical Name||Rehmannia elata|
|Common Name||Chinese foxgloves|
|Plant Type||Annual flower|
|Mature Size||2 to 3 feet wide, 1.5 to 3 feet wide|
|Sun Exposure||Full sun, partial shade|
|Soil Type||Well-draining, rich soil|
|Soil pH||6.5 to 7|
|Bloom Time||Summer, fall|
|Flower Color||Pink, purple|
|Hardiness Zones||7 to 10|
How to Grow Chinese Foxgloves
The prolific blooms are long-lasting and will repeat bloom for three to four months, unlike traditional foxgloves. The plants might flop over as the older blooms make way for younger blossoms, so you can stake it to keep it upright if desired.
Spring-planted seeds may not bloom the first year, but to get around this frustration, you can plant the seed in the fall for gorgeous flowers during the following summer. Although Chinese foxgloves are not as hardy as their lookalikes, digitalis, they are more versatile, growing well in shade and even fairly drought-tolerant.
Chinese foxgloves help to light up shade gardens and that is where they grow happiest. They begin blooming as spring woodland flowers fade. They provide a nice accent to Hosta and the glossy leaves and nodding blossoms contrast well with Astilbe. Because the plants can be fairly wide, give them some space when planting in a garden. It can become invasive in certain areas, particularly when grown in moist, rich soil. If your plant starts to become aggressive, cut back on either food or water, to stress the plants and slow their growth.
You can grow Chinese foxgloves in full sun to partial shade. Although the plant prefers sun, they will still flower quite well in shade and can even handle dry shade. In full sun, they will need extra water during hot spells.
Chinese foxgloves are not particular about soil pH, although they do best in a neutral pH of about 6.5 to 7.0. However, they do need well-draining soil, which can be chalky, sandy, or loamy. The root will rot in soil that remains wet for extended periods. Poor-draining soil can also cause problems during the colder winter months.
For best results, water daily by using a soaker hose or drip irrigation, especially during the first year. Once established, Chinese foxgloves have good drought-tolerance, but mostly in the shade. The plant can tolerate being watered just once a week, but the flowers won't be as prolific as if it was watered every day.
Temperature and Humidity
Chinese foxgloves are only hardy in USDA Hardiness Zones 7 to 10, though they grow as a perennial in zones 8 to 10. In zone 7, it's unpredictable and is more likely to grow as an annual. Chinese foxglove plants cannot handle freezing temperatures and should be given some protection, like a thick layer of mulch, during cold winters.
A side dressing with compost or monthly feedings will also help promote flowering. Feed the plant with liquid fertilizer during the summer months to keep the blooms growing.
Propagating Chinese Foxgloves
You can divide your plants in the spring, but because they spread so readily, you probably won't need to. You'll have plenty of plants and if some die out, new ones fill in.
Chinese foxgloves are fairly low-maintenance. Plants should be deadheaded for continual bloom.
Growing in Containers
Chinese foxglove also grows happily in containers, if given regular feedings to encourage blooms. In areas colder than zone 7, you can try starting over-wintering plants indoors or grow your Chinese foxgloves in containers and move the containers to a sheltered and protected spot for winter. Make sure the containers get periodic water and allow it to drain. Lifting the container off the ground with a couple of bricks will ensure the drainage holes are not blocked by frozen ground.
Growing From Seeds
Start Chinese foxglove seeds indoors for best results. Although they can be sown outdoors once the risk of frost has passed, the plant's small seeds can be easily overwhelmed. Sow the seeds in good potting soil in small pots, seed trays or plug trays. Expect germination within 15 to 30 days, depending on temperature, and then transplant out when the plants are at least 6 inches high. You can expect the plant to bloom about 70 days after germination if conditions are right.
Common Pests and Diseases
Although Chinese foxgloves are generally pest free, slugs and snails may munch on its leaves.