- Full Sun (At Least 6 Hours Of Direct Sunlight)
- Mature Height 5 - 6 Feet
- Mature Spread 5 - 6 Feet
- Growing Zones 3 - 9
- Use As A Thriller In Containers
Unlike other hollyhocks, which typically live only 2 years, Blacknight Hollyhock (Alcea rosea ‘Blacknight’) is a perennial version of the tall, sun-loving flowers. And you will be glad it comes back, since the flowers on Blacknight are, well, nearly as dark as night. The maroon-black blooms are the perfect frontman for a wall or fence, as the plants will come to grow 5 to 6 feet high and spread flowers across their nearly 2-foot spread. Hummingbirds and butterflies will be thrilled when they visit the blooms.
The large, single-type flowers and round, lobed leaves of the hollyhock can evoke a cottage feel or a natural and colorful effect, depending on how you plant them. They do contrast best with a solid backdrop, and tend to need no staking if located near a fence or wall. However, feel free to place these beauties in the middle of a garden bed if you want some tall, dark color. Hollyhocks love sun and this Blacknight variety should come back each year (as a short-lived perennial) in zones 3 through 9.
Blacknight Hollyhock Care
Be sure to plant your hollyhock in a spot that receives at least 6 hours of sun a day. If you choose to plant them in an open site, be aware that the plant might need some staking while in full bloom, although the stalks are strong. The plants benefit from average soil fertility, but can grow in any soil that drains well. Regular water helps a hollyhock bloom, but established plants can handle some drought. The plants tend to grow quickly, but giving them some compost or a balanced fertilizer in spring as they reappear gives them a yearly boost.
Hollyhocks do not need deadheading, but pinching off dried-up blooms can help keep the plant looking cleaner. In fall, prune your hollyhock back to about 6 inches above the ground. Spread a thick (4- to 6-inch layer) of straw or other mulch around the ground above the roots to help protect the plant. Remove the mulch once danger of frost passes in spring.
Blacknight Hollyhock Spacing
For a stunning black border or cottage row effect, plant several hollyhocks together. Be sure to space the young plants about a foot apart to give each room to spread in summer.
Blacknight Hollyhock Information
USDA Hardiness Zones: 3 - 9 |
Plant Type: Perennials |
Light Exposure: Full Sun (At Least 6 Hours Of Direct Sunlight) |
Mature Height: 5 - 6 Feet |
Mature Spread: 24 Inches |
Spacing: 24 Inches |
Habit: Upright |
Flower Color(s): Purple |
Flower Description: Purple Shades To Near Black Shades |
Bloom Period: Mid-Summer |
Foliage Type: Herbaceous |
Foliage Color(s): Green |
Foliage Description: Green shades |
Seasonal Interest: Summer Flowering |
Watering: Average |
Resists: Pests & Insects |
Tolerates: Drought |
Attracts: Butterflies, Hummingbirds |
Container Role: Thriller |
Uses: Borders, Containers, Mass Planting, Specimen or Focal Point, Wildlife Gardens |
Features: Attracts Pollinators, Cut Flowers, Low Maintenance |
Brand: Proven Winners |
Common Name: Blacknight Hollyhock |
Other Name(s): |
Scientific Name: Alcea rosea |
- SKU:
- ALCBL
Container Sizes
Please Note: The pictures below are to give a general representation of the different container sizes. The actual size/ages of plants are estimates and will vary based on; type of plant, time of year, last pruning & many other factors.
For more detailed information, please click here.
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Standard Colors: 2-3 business days
Special Order Colors: 8 weeks - this is due to the planter being custom made with the color(s) of your choice
Please Note: On special orders there can not be any cancellations
Plant Shipping
Time of Order:
Summer Shipping
- If there is extreme heat we’ll delay shipping.
- We’ll have to review what areas the plants are traveling through along with your location
Once your plant is shipped you’ll receive an email with tracking information. Depending on the above criteria we’ll ship your plant(s) towards beginning of the following week from your order. We put together this helpful guide of what to do when you receive your plants in the mail.
It is important to know that all of our plants are clearly labeled for which growing zones the plant can survive in. The plants are thoroughly trialed and tested in every growing zone before we state the plant can grow in a zone. Again, our #1 priority is to ship the plants to you healthy and ready to thrive in your location. So we will do everything in our power to do so.