Helleborus - Hellebore

Flower Color

Height

Season

Pests

Uses

Propagation

 pale green, pink to cream

18" - 24" 

late winter to spring 

few

shade garden, border

division, seeds

Performance - Hellebores perform best in partial shade to full sun in a well drained soil with organic matter additions. These plants are drought tolerant once established, but mulching is often needed during the winter.

Comments - If propagating by seed it is important to sow immediately to break the long dormancy period.  This species often takes up to 2 years to germinate. Hellebores look best in areas where early flowering can be seen up close, such as patios and walkways.

Helleborus argutifolius - Corsican hellebore
Helleborus foetidus - Bearsfoot hellebore
Helleborus niger - Winter hellebore
Helleborus orientalis - Lenten Rose

Hemerocallis - Daylily

Flower Color

Height

Season

Pests

Uses

Propagation

yellow, orange, white, pink, salmon, bicolors

15"- 48"

early summer

aphids, leaf spot

border, mass planting

division


Performance - Daylilies are a traditional and common perennial garden plant in the Kentucky landscape. They are easy to grow in most garden sites but prefer full sun and well-drained soils. They will tolerate semi-shade locations. Each bloom lasts only one day (thus the name daylily), numerous buds are produced so an individual may flower for 3 weeks or more.

Comments - These plants are available in a wide range of bloom colors, forms, plant heights, and bloom sizes. Thousands of cultivars are available, all of which have something to offer the flower garden. Mid- to late June is considered the prime blooming time for Hemerocallis. There are daylily societies and breeders in Kentucky where a gardener can find more information and many different types of plants.

Varieties - Over 20,000 named varieties are available, but commonly available varieties include 'Bitsy', 'Eenie Weenie', 'Fairy Tale Pink', 'Happy Returns', 'Hyperion', 'Midnight Magic', 'Red Joy', 'Siloam Double Classic', 'Spider Man', 'Stella d'Oro.

Hesperus matronalis - Dame's Rocket, Sweet Rocket

Flower Color

Height

Season

Pests

Uses

Propagation

lavender, white

24"- 36"

late spring

aphids

natural garden, border, mass planting

seed

Performance - Dame's rocket is a relatively common, old-fashioned perennial used in Kentucky gardens. This plant is native to Europe and has escaped from U.S. gardens or is planted in wild flower areas. Some would consider this plant to be an invasive exotic plant, but it does produce a spectacular show in the spring garden. Be sure to plant other summer flowering annuals or perennials around it so its summer absence doesn't leave a big hole in the garden.

Comments - The plants are usually biennials, but most people don't notice that the seeds have germinated in the fall; they only notice the flowers in the spring. There are white and double varieties.

Heuchera - Coral Bells, Alum Root, Crimson Bells

Flower Color

Height

Season

Pests

Uses

Propagation

pink, red, white

8"- 30"

late spring, summer

few

border, mass planting

seed, division

Performance - Heucheras are an underused but reliable perennial plant for Kentucky landscapes. The plants have evergreen leaves and perform best in a semi-shade or shade location. They prefer well-drained soil, but need regular irrigation during the summer for best performance.

Comments - The dainty blooms or the strikingly colorful foliage can add a great deal to the landscape. Gardeners need to try more coral bells; they will be pleased with these plants. Many varieties are available from four or more species (H. americana, H. micrantha, H. sanguinea, H. x brizoides) of these native American plants.

Varieties -
Colored foliage - 'Bressingham Bronze', 'Carousel', 'Cathedral Windows', 'Eco-Improved', 'Mint Julep', 'Palace Purple' (1991 Perennial Plant of the Year), 'Pewter Moon', 'Plum Puddin', 'Ruby Veil', 'Silver Veil'.
Floral display - 'Bressingham Hybrids', 'Chatterbox', 'Coral Cloud', 'June Bride', 'Mt. St. Helens,' 'Raspberry Regal', 'Tattletale', 'White Cloud'.

In trials at the UK Horticulture Research Farm from 2000 to 2006, Heuchera ‘Amethyst Mist’, ‘Purple Petticoats’, Heuchera micrantha 'Palace Purple', Heuchera sanguinea ‘Canyon Pink’ and ‘Splendens’ received the highest ratings, Heuchera x brizoides 'Bressingham Hybrid’ received moderate ratings and Heuchera ‘Amber Waves’ died in the first winter.

Heuchera ‘Palace Purple’

Heuchera ‘Bressingham Hybrids’

Heuchera ‘Amber Waves’

X Heucherella - Foamy Bells

Flower Color

Height

Season

Pests

Uses

Propagation

white, pink

15"- 24"

spring

few

shade garden, ground cover

division

Performance - Foamy bells are a reliable perennial for shade gardens in Kentucky landscapes. This plant is not commonly used, but offers another alternative for shady areas. The plants spread by stoloniferous branches to fill a garden area.

Varieties - 'Bridget Bloom', 'Pink Frost', 'Snow White'.

Hibiscus - Hibiscus

Perennial and annual hibiscus are commonly used in Kentucky gardens because they prefer our warm summer conditions and they have large showy flowers.
 

Flower Color

Height

Season

Pests

Uses

Propagation

white, red, pink, yellow, orange, bicolors

3-8 ft.

summer

Japanese beetles, caterpillars

border

cuttings, seed, division

Hibiscus moscheutos - Rose Mallow

Hibiscus moscheutos ‘Etna Pink’

Hibiscus moscheutos ‘Lord Baltimore’

Performance - Rose mallow is a reliable perennial plant for Kentucky landscapes. The plants should be grown in full sun sites, but they will tolerate partial shade. They perform well in most soils. The stems die back to the ground each winter, so remove the old stems in the spring. Give these plants plenty of room in the landscape.
Comments - These plants produce blooms that average 6-8" in diameter and are very showy. Plants grown from seed take several years to reach a mature size. The 'Frisbee' hybrids are about 4 feet tall and are a better choice than older forms that require staking.
Varieties - 'Ann Arundel', 'Disco' series, 'Frisbee', 'Lady Baltimore', 'Lord Baltimore', 'Southern Belle'. The following cultivars of Hibiscus moscheutos have had outstanding performance in trials at the UK Horticulture Research Farm from 2000 to 2006: ‘Disco Bell Pink’, ‘Disco Bell White’, ‘Kilimanjaro Red’, ‘Lord Baltimore’, ‘Rainer Red’, ‘Mauna Kea’, ‘Etna Pink’, ‘Matterhorn’, ‘Luna Blush’, ‘Luna Red’, and ‘Luna White’.

Hibiscus rosa-sinensis - Rose of China, Hawaiian Hibiscus

Performance - Rose of China is an outstanding annual shrub grown in patio containers or in the landscape. Plants are purchased in the spring and perform well in full sun locations all summer. They require plenty of water and fertilizer throughout the summer for best performance.
Comments - Hibiscus can be grown indoors as a house plant in a sunny window. The plants are difficult to propagate from cuttings in the home, so it is best to purchase new plants each year.
Varieties - Many different colors are available.

Hibiscus trionum - Annual Hibiscus

Performance - Annual hibiscus is easy to propagate from seed and performs quite well under Kentucky garden conditions. This annual is attractive for its narrow, upright growth with cream-colored funnel shaped flowers. Water potted specimens frequently and tip prune young plants to promote bushiness.
Comments - This plant can self-sow quite easily and has been known to become a garden and agricultural weed. It is probably best not to grow this invasive exotic plant.
Varieties - 'Simply Love'