What Grows There :: Hugh Conlon, Horticulturalist, Garden Advisor, and Photographer

Lovely Fruit Capsules Fill Sweetheart Tree In Late Summer

Posted by Hugh on July 26th, 2020

Korean sweetheart tree (Euscaphis japonica) is a large flowering shrub or small deciduous tree that is native to mountain valleys, open forests and thickets in China, Korea and Japan (USDA hardiness zones 6 to 8). Dr. J. C. Raulston discovered Korean sweetheart tree in 1985 on the Korean Peninsula during a plant expedition. Yet, it is still relatively unknown in American gardens. Sweetheart tree belongs to the bladdernut (Staphyleaceae) family

It typically matures to 12 to 20 feet tall, occasionally upwards to 30 feet and a spread of 8 to10 feet wide. Leaves are opposite pinnately compound, a single leaf 6-10 inches long. Each leaf is composed of 7-11 thick, leathery, finely toothed, glossy, dark green leaflets, 2-4 inches long. The deciduous leaves turn mahogany-purple hue in the fall.

This durable tree thrives in a variety of soils, preferably moist, for sweetheart tree to bloom and bear numerous fruits. The tree should be planted in partial to full sun. The yellowish-white flowers (each to 1/4” diameter) appear in spring (May-June) in 6-9 inch long terminal panicles and go by mostly unnoticed. It tolerates brief periods of drought, and performs best in moist soils. Avoid areas of the U.S. where summers are extremely hot and droughty.

The smooth purplish-brown gray bark is lined with white striations for winter interest. Its pinnately compound foliage displays an interesting textural character. The late summer fruits shaped like tiny heart-shaped red capsules, hence the name “sweetheart tree”.

Without question, plant collectors grow sweetheart tree for its showy clusters of heart-shaped fruits. Starting in early August, ripening fruits morph from green to pink to red. In early to mid-October capsules split open revealing a tiny, shiny, black seed. The jet black seeds hang from the tree branches. Wildlife attraction to the fruits is not known.

No serious insect or disease problems trouble this highly ornamental small tree. The tree is sold by specialty nurseries found on-line.

Korean Sweetheart Tree (*Euscaphis japonic*a)

Favorite Native Shrub Pollinators

Posted by Hugh on July 21st, 2020

These eight (8) shrubs amaze me by the numbers of bees and other pollinators that their flowers attract when blooming.

Virginia sweetspire (Itea virginica) is an erect, rounded, broad-spreading, deciduous shrub with arching branches. Itea grows 3-4 feet (less frequently to 5 feet) tall with similar spread. Fragrant, tiny white flowers borne in cylindrical, drooping racemes (3-6 inches long) cover the shrub from late spring to early summer. Oval, dark green leaves (1-4 inches long) turn varying shades of red, orange and gold in autumn. (USDA Hardiness Zones 5-9).

Elderberry (Sambucus canadensis) are known for their creamy white blooms against the glossy green foliage. Laceleaf and purple colored leaves are very ornamental. Elderberries attract great numbers of bees and other pollinators. They prefer a moist well-drained soil. (Zones 3-9).

Bottlebrush buckeye (Aesculus parviflora) spectacular 8-12 foot tall and 12-15 feet wide suckering summer flowering shrub in partial sunny areas; 8-12 inch white bottle brush flowers with showy red anthers and pinkish filament sand attractive dark green palmate leaves that turn bright yellow in the fall. (Zones 5-8).

Summersweet (Clethra alnifolia) grows 3-8 feet high. depending on cultivar. Sweetly fragrant white 2-6 inch long flower panicles attract hundreds of bees and butterflies in July. Flowers give way to dark brown seed capsules (1/8 inches diameter) which may persist into winter. Glossy dark green leaves (3-4 inches long) transition to shades of golden yellow in fall. (Zones 3-9).

Coralberries (Symphoricarpus spp.), represent several low ground cover shrubs. They produce tiny summer flowers which are browsed by many pollinators and fruits persist well into winter along arching stems. (Zones 2-7).

Bluebeard (Caryopteris spp.), aka blue mist shrub, is covered with brilliant blue blooms in late summer into fall and bees and butterflies come to them. (Zones 5-9).

Red Chokeberry (Aronia arbutifolia) grows 6-10 feet tall with spring blooms. Chokeberry grows in a stiff, upright vase shape habit and exhibits a fibrous rootsystem that suckers freely. Fruits are eaten by birds and other animals. (Zones 4-9).

Black chokeberry (Aronia melanocarpa) is another May blooming upright spreading, suckering shrub. It grows 3-6 feet tall with 5-6 flower clusters of white 5-petals which leads to tart, almost bitter black berries and purple/red fall leaf color in late summer. (Zones 3-8).

Beebalm (Monarda) Varieties Attract Hummingbirds, Butterflies And Moths

Posted by Hugh on July 16th, 2020

In 2016 Mt. Cuba Center in Greenville DE enlisted a team of trained volunteers to monitor the visitation of hummingbirds, moths, and butterflies in the 40 cultivar beebalm (Monarda) trial. Their goal was to systematically observe and note the cultivars that were most frequently visited by these pollinators. Below is a listing of the five most-visited selections by hummingbirds and moths/butterflies.

MT Cuba plant scientists report: “One of the first things we learned from this data is that hummingbirds visit large-flowered, red cultivars almost to the exclusion of everything else. This is most likely due to the fact that hummingbirds require a larger flower size in order to access the nectar. Despite the floral similarities among the hummingbird-visited selections, ‘Jacob Cline’ was much more favored than any other cultivar.

They report: “It is hard to pinpoint an exact cause, but one possible explanation may be that ‘Jacob Cline’ is the tallest of these cultivars and therefore may be easier for the hummingbirds to visit. Just as hummingbirds favored a certain type of flower, so too did moths and butterflies. They were most frequently observed visiting selections that produced the largest abundance of 2-3 inch wide flowers.”

Beebalm (Monarda) Varieties Attract Hummingbirds, Butterflies And Moths The data demonstrate that there are horticulturally desirable characteristics of cultivars (i.e. improved flower production and longer bloom times) that can have a positive impact on ecological function. For example, M. fistulosa ‘Claire Grace’ is a top performer horticulturally as well as a favorite among moths and butterflies.

Attracting Hummingbirds

1. M. didyma ‘Jacob Cline’

2. M. ‘Gardenview Scarlet’

3. M. ‘Cambridge Scarlet’

4. M. didyma

5. M. ‘Raspberry Wine’

Moth/Butterfly

1. M. fistulosa ‘Claire Grace’

2. M. ‘On Parade’

3. M. ‘Violet Queen’

4. M. ‘Peter’s Purple’

5. M. ‘Colrain Red’

Caveat: you should not conclude from a one year study that 2 or 3 varieties were the best. Hummingbird and insect activity may vary with the choice of varieties and the summer time period. Beebalms are also able to support an incredible number of bee and wasp species.

Indian Pinks Generate Garden Fireworks

Posted by Hugh on July 11th, 2020

Indian Pinks Generate Garden Fireworks

Indian pink (Spigelia marilandica) is a strikingly beautiful native wildflower native to the Southern Appalachian region. However, this perennial grows well in most parts of the country (Zones (5b)6-9). Plants emerge quite late in the spring. Sometime in June, depending on locality, their bright red tubular flowers flare open, crowned by five sharply pointed pale yellow reflexed lobes. By the 4^th of July flowers will produce floral fireworks in your garden.

Indian pink prospers around a rich moist open woodlands or shade garden. They grow equally well in mixed containers. Plant in a well-drained, mildly acidic soil that is generously amended with compost or humus. A partially sunny site in full morning to dappled sunlight is perfect. Irrigate during dry periods and do not allow plants to stand in water.

In older plantings vigorous plants will grow 2 to 3 feet tall. Leaves are
are arranged opposite on the stem, attached directly to the main stem (no petioles), ass well as an entire (toothless) margin. Plants stand erect and are rarely branched.

New plantings of Indian pink often start off slowly, taking 2-3 years to reach maximum flowering. Create a dazzling display by setting five or more plants en masse. Over the years in good humus-rich soil, Indian pinks often naturalize and look stunning. Flowering time is extended over several months by swift removal of the old spent flowers (deadheading).

The brightly colored flowers attract numerous pollinating insects and hummingbirds. No disease and pest problems cause Indian pink any troubles.

The popularity of Indian pinks continues to increase. In recent years, the U.S. native plant industry have been bulking up plant inventories. Tissue culture labs are also producing them. ‘Little Redhead’ is a superior vegetatively propagated strain that grows very uniformity.

Attracting Hummingbirds

Posted by Hugh on July 6th, 2020

This time of year many gardeners are setting out bird feeders, including those filled with a sugar solution to encourage hummingbirds to visit your garden. Unfortunately, the sugary drink will also attracts numerous ants, bees, and wasps. When warm spring and summer weather arrives, the solution clouds up with bacteria which ferments or perhaps fatal to the birds. In addition to adding feeders, plant several woody trees and shrubs, perennials, and annuals to your landscape, raised beds and containers.

The kinds of flowers that attract hummers are tubular in shape and red in color, although they’re frequently seen visiting orange, yellow, purple or even blue flowers, offering you plenty to choose from. Avoid considering double-flowered forms which are poor nectar producers and aren’t attractive to pollinators.

Here are some of my favorite hummingbird plants:

Perennials:

Anise hyssop (Agastache spp.)

Foxglove (Digitalis purpurea)

Daylilies (Hemerocallis spp.)

Blazing Star (Liatris spicata)

Red cardinal flower (Lobelia cardinalis)

Great blue lobelia (L. siphilitica)

Lupine (Lupinus perennis)

Beebalm (Monarda spp.)

Catmint (Nepeta spp.)

Beardstongue (Penstemon spp.)

Garden phlox (Phlox paniculata)

Sage (Salvia spp.)

Annuals:

Snapdragons (Antirrhinum spp.)

Cuphea, cigar plant (Cuphea spp.)

Impatiens (Impatiens spp.)

Lantana (Lantana spp.)

Cypress vine (Ipomoea quamoclit)

Flowering tobacco (Nicotiana spp.)

Salvia (Salvia spp.)

Zinnia (Zinnia spp.)

Woody plants:

Mimosa tree (Albizia julibrissin)

Trumpetvine (Campsis radicans)

Rose of Sharon (Hibiscus syriacus)

Coral honeysuckle (Lonicera sempervirens)

Azaleas and rhododendrons (Rhododendron spp.)

Weigela (Weigela florida)

Torch Lilies (Kniphofia)

Posted by Hugh on July 1st, 2020

Torch lilies (Kniphofia spp.) are easy to grow long-lived perennials from South Africa that are remarkably (USDA hardiness zones 5-9). They go by a number of common names including red hot poker and tritoma. The colorful floral spikes (and a little imagination) resemble fiery torches or sizzling pokers, visited often by hummingbirds, bees and butterflies.

New cultivars are mostly hybrids and vary in plant height and flower color. One or more floral spikes arise 18 inches to 4 feet in height, depending on the cultivar(s) planted. Color choices include off-whites, yellows, oranges, reds, and blends of two or more tints. From May thru October additional re-blooming follows soon after the spent floral scapes have been pruned off (deadheaded).

Torch lily excels when planted in average well-drained soil. Full to partial (6 hours minimum) sunlight is ideal. Most, but not all, cultivars are cold hardy in the Southern Appalachian region (USDA zones 6 and 7). The sharp edged grass-like foliage is evergreen and tends to take a beating in rough winters. Prune back the entire plant near the soil line in late winter for a fresh start.

Modern varieties tend to grow shorter (under 20 inches) compared to the species, K. uvaria, which grows 3 feet and higher. Terra Nova Nurseries, an Oregon wholesale nursery, offers two series of dwarf Kniphofia that are bred for the both the container and perennial garden market. The Poco® series has 4 color variations and the Popsicle® series comes in 7 hues. Late blooming ‘Fire Glow’ is a lovely 14-inch dwarf Kniphofia with large bi-color orange and red flower spikes that flower later from August to October. The Echo® Series, offered by Itsaul Nursery in Atlanta Georgia, grow 30-48 inches high, depending on cultivar. Echo Duo (
reddish-orange), Echo Mango (apricot), and Echo Rojo (orange-creme) are popular choices.

A 2-year and older plant clump is both heat and drought tolerant. Every 3-4 years rhizomes are dug and divided either in early fall or late winter. Torch lily has few serious disease and insect problems. Root rot may become a significant problem when planted in a poorly drained soil.

Compass Plant – Prairie Giant

Posted by Hugh on June 26th, 2020

Compass Plant (Silphium laciniatum) are impressive prairie plants that look like – but are not – sunflowers. Native to the central U.S. (USDA hardiness zones 3 to 8), these sturdy prairie giants grow upwards of 5-8 feet in height (1.5 – 3 feet wide) on stiff, hairy, resinous stems. The group (Silphiums) are also called “rosinweed” because split or broken stems exude a gummy rosin (resin).

Their sunflower-like flowers measure 4-5 inches in width with yellow rays and yellow center disks. Flowers bloom in loose spikes on the upper parts of the plant in summer. Leaves are very large and deeply cut. The bottom (basal) leaves measure upwards of 18 inches in length. Basal leaves usually orient themselves on a north-south axis so as to minimize intense overhead sun exposure, thus giving rise to the common name.
The upper leaves are a lot smaller.

Compass plant is easily grown in average, medium moist, well-drained soils in full sun. This prairie giant tolerates poor soils and asks for little or no care. In partial shade, staking plants may be necessary.

No serious insect or disease problems trouble compass plant. Plants from seed may be slow to establish and may not flower until the second or third year. Flowers attract butterflies, bees, and other pollinators. Don’t be in a hurry to cutback plants in the winter as birds perch upon the stems of these architectural giants.

Because of their enormous height, compass plants are best sited in the rear of a flower border where they should prosper over many years. They make excellent additions to a prairie or wildflower gardens.

Prairie species like compass plants are rarely sold at local garden centers. Mail order seed companies like American Meadow, Inc. are your best place to shop.

Gaura (Wand Flower)

Posted by Hugh on June 21st, 2020

Gaura (Gaura lindheimeri), also known as wand flower, whirling butterfly, and bee blossom (Gaura lindheimeri) is one tough perennial that blooms through the summer into fall. Gaura is native to Texas and Louisana and is hardy to USDA plant zones (5)6-9. It lives many years in hot humid climates and requires very little care after the first year.

Plant heights range from 15 inches to 4 feet (see variety list below). Many cultivars are compact and that makes them container-friendly as well. Gaura foliage is lance-shaped, often tinted with pink, white, and cream (depending on variety). Wiry flower stems bear numerous 1-inch 4-petalled flowers. Color palette is white, pink, reddish, or color blends. Heaviest blooming occurs in early summer, but plants often flush full of flowers through summer / early fall and are visited by bees, butterflies, and an occasional hummingbird or two.

Flowers catch your eye as fluttering wands (stems) of white or pinkish flowers. Compact varieties of gaura are also make good pot fillers. Flowers may appear delicate but gauras are one exceptionally tough perennial. Cut taller varieties back by one-half in the early days of summer to promote compactness. Also, remove old spent cut floral stems back; new stems will rush up and plant(s) will re-bloom. Disease and pest problems along with deer rarely trouble gaura.

Plant gaura in a sunny location that captures 6 to 8 hours of direct sun daily and in average well-drained soil. Gaura develops a deep taproot and is rated as highly drought tolerant. Irrigate gaura the first year and enjoy not having to reach for a watering hose in subsequent summers. Feed plants with a slow release fertilizer in spring. Annual mulching is highly recommended for long term plantings.

Popular varieties:

‘Siskiyou Pink’ – favorite old-timey variety with deep pink flowers

‘Whiskers Deep Rose’ –ultra compact (14-16 inches tall) with rosy-pink petals and white stamens, all above burgundy-tinted foliage.

Whirling Butterflies® – bright white flowers with red sepals; compact (36 inches tall); free flowering and don’t self-seed.

Sparkle White (2014 All-American Selection (AAS) winner)- 24 inch tall compact.

Four Landscape Shrubs That Are Early Summer Stars

Posted by Hugh on June 16th, 2020

Bottlebrush buckeye (Aesculus parviflora) is one of our finest early summer native flowering shrubs for sun or shady sites. It is a dense, mounded, suckering, deciduous, multi-stemmed shrub which grows 6-12 feet tall and 15-18 feet spread. It flaunts unique palmate green leaves (5-7 leaflets) and white 10-12 inch tall floral candles. The dynamic bottlebrush florets reveal conspicuous red anthers and pinkish filaments. Glossy inedible, pear-shaped husks containing nuts (buckeyes) appear in early fall. Finally, the foliage turns yellow in autumn. (Zones 4-8)

Summersweet (Clethra alnifolia) is a deciduous native shrub found in the wild in moist woodlands, stream banks and seashores from coastal Maine to Florida and west to Texas (Zones 3-9). This rounded, suckering, densely-branched, deciduous shrub grows to 3-6 feet (less frequently to 8 feet) tall and is noted for producing a mid-summer bloom show of sweetly fragrant white (or pink), 2-6 inches long, upright flower panicles (racemes). Flowers give way to dark brown seed capsules which often persist into winter. Serrate, obovate to oblong, glossy, dark green 3-4 inch long leaves. Expect an attractive yellow to golden brown fall leaf color. Flowers attract to butterflies and bees.

Buttonbush (Cephalanthus occidentalis) is a deciduous native shrub with an open-rounded shrubby form that typically grows 6-12 feet tall (occasionally to 20 feet). Tiny, tubular, 5-lobed, fragrant white flowers appear in dense, spherical, long-stalked flower heads (to 1.5 inches in diameter) in early summer. Long, projecting styles give the flower heads a distinctively pincushion-like appearance. Flower heads attractive bees and butterflies. Flower heads mature into hard spherical ball-like fruits consisting of multiple tiny two-seeded nutlets persist through most winters. Ovate to elliptic glossy bright green 4-6 inches long leaves form in pairs or whorls in late spring (May). (Zones 5-9)

Chastetree (Vitex agnus-castus) is typically grown in warm winter climates as a vase-shaped, deciduous shrub to 10-15 feet tall or trained as a single trunk tree to 20 feet tall. This non-native will grow as a 3-5 feet tall herbaceous perennial in colder parts of the U.S. (zones 5). Its grayish-green aromatic, palmately compound leaves are comprise of 5-7 lance-shaped leaflets (each leaflet to 6 inches long). In early- to mid- summer 9-12 inch floral panicles of tiny, fragrant, lavender to pale violet flowers attract loads of nectar hungry butterflies and pollinators. (Zones 6-9)

Hakone Grass – On The Shadier Side Of A Garden

Posted by Hugh on June 11th, 2020

‘Aureola’ hakone grass

Japanese Forest grasses, also called Hakone grasses (Hakonechloa macra), hail from Japan (USDA hardiness Zones 5-9). They are a wonderful choice in a drab woodland garden spot. You will love them for their bright foliage and low growing habit.

Hakone grass grows in a mounding clump. The foliage cascades over rocks, edges over garden walls, or off the rims of containers. It spreads slowly via rhizomes into a luscious ground cover.

The species itself (H. macra) has its green foliage, tolerates a bit more sun and drier soils, and is much faster growing compared to the brightly tinted cultivars. Four selections, including the species are highlighted here.

‘Aureola’ – this green and gold streaked cultivar was selected the Perennial Plant of the Year in 2009. Leaf coloring is more prominent in deep shade and less so in sunnier spots.

‘All Gold’ – foliage is chartreuse or all gold as its name implies, a wonderful accent plant associated with other colored foliage plants grown in containers or garden beds.

‘Fubuki’ forms a low mound of narrow green and creamy white striped 14 inches tall and 18 inches wide sedge; leaves develop pink tones in autumn; grows very compact than related cultivars.

‘Beni-kaze’ (Red Wind) produces short wide green blades which turn partially red in summer and most leaves take on a red to purple tint in fall.

Plant hakone grasses from spring thru mid-summer to allow adequate time for the plant’s root system to develop before the arrival of winter. Hakone grasses prefer a partial sunny to partial shade location and humus-rich, moist, well-drained, slightly acidic soils. In northern locales full morning sunlight or full day dappled sites are perfect. The grass tolerates almost full shade in the hot, humid deep South.

Feed lightly in spring with granular 20-10-10 or equivalent fertilizer or water soluble fertilizer 2-3 times in spring and summer months. Clip back (or mow off) last year’s clumps a few inches from ground in late winter.