New Hybrid Bleeding Hearts

Dicentra 'Luxuriant' 

Bleeding hearts bloom in April into May (in Tennessee - zones 6 and 7). In cooler northerly locales, flowering may continue into summer.  The bright red, pink or white, heart-shaped, pendant flowers are supported on arching stems.

Bleeding hearts (Dicentra spp.) are truly one of nature’s glorious delights in the spring - early summer garden (USDA hardiness zones 3-9). Old fashion bleeding hearts (D. spectabilis), indigenous to Asia, grow taller and wider compared to their North American counterparts wild bleeding heart (D. exima) and Dutchman's breeches (D. cucullaria).

A number of new cultivars have been released in recent years that are hybrid crosses between D. peregrine (native to Japan) x D. exima (native to eastern North America) x D. formosa (native to Western U.S.). These bleeding heart grow more compact and robust, are longer flowering, exhibit blue-gray foliage, and offer more floral color choices.

Four notable hybrid cultivars include 'Luxuriant' (D. eximia  x D. formosa  - deeply-cut,  grayish-green foliage and cherry red blooms. ‘King of Hearts’ (D. peregrina x D. formosa subsp. oregana x D. eximia) - very compact grower only 9 inches high and 14 inches wide. 'Fire Island' (D. peregrina x D. exima) - white tipped magenta red flowers from late spring into midsummer and 12 inch x 20 inch mound of frosty blue foliage. ‘Valentine’ - a vigorous hybrid form with showy cherry red/white tipped flowers.

New hybrid forms tend to grow more vigorously and are spaced 24-36 inches apart. Good soil drainage is essential for bleeding hearts. Plant in a humus-rich mildly acidic soil along with more hours of sunlight, preferably in the morning. Lightly mulch around plants in a woodland garden. In late winter feed a slow-release fertilizer at the low package rate.

In southern locales hybrid forms generally die back (go dormant) by mid-summer unless regularly irrigated. Crowded clumps should be divided either in very early spring or after flowering.

Spring flowers attract butterflies and hummingbirds. Aphids, slugs and snails occasionally feed on the leaves. Plants are deer and rabbit resistant.

Bleeding hearts are great companions with other woodland plants such as ferns, lungworts (Pulmonaria spp.), brunneras, coral bells (Heuchera), and foam flowers (Tiarella).

Note: in recent times the genus Dicentra has been changed to Lamprocapnos.

Early Flowering Magnolias

'Leonard Messel' Magnolia

Early flowering magnolias (M. ×loebneri ) are excellent choices for a small flowering yard tree. This deciduous hybrid magnolia (M. kobus x M. stellata) includes some hybrid crosses including 'Leonard Messel', 'Ballerini', and 'Merrill'(zones (4)5-9).

Additional hybrid cultivars are also available in commerce that feature more compact forms and flowers (called "tepals") that are white, blush-pink, lilac pink or pink depending on cultivar.

In general, deciduous magnolias start out as slow growing large shrubs or small trees. At maturity they reach 25 feet and a rounded crown. Despite their early blooming, some flowers often escape freezing temps. In the case of first to bloom star magnolia (M. stellata), flowers may open over a 3 week interval.

  

My favorite cultivar in the group is 'Leonard Messel'. This small tree is often grown multi-trunked rather than a single trunk tree. Flowers measure 4-6 inches across with 10-15 petals. Flowers give way to cone-like fruits that age to a reddish tinge in late summer; fruits split open to distribute individual red coated seeds suspended on slender threads. Fruits are sometimes absent on some hybrid magnolias if inadequately pollinated.

Flowering magnolias are best grown in moist, organically rich, well-drained loams in full sun to part shade. Trees are generally intolerant of soil extremes (dry or wet) and intolerant of most urban pollutants. Young trees may take 3-4 years before first blooms appear. Magnolias are best sited in a site sheltered from high winds.

Leonard Messel magnolia has a multi-branched  habit and start producing their lovely flowers at an early age. No serious disease or pest problems trouble this cultivar when properly sited at planting. The 5-inch long, medium green obovate leaves remain blemish-free through the growing season. Its gray bark of deciduous magnolias is an added plus, particularly over the winter months. 

Growing Siberian Iris

'Caesar's Brother'

Siberian irises are favored by many gardeners  over the more popular bearded irises for their ease of maintenance, longevity, and disease and pest resistance. Their flowers are smaller than bearded iris blooms, but their grass-like foliage looks attractive all season long. Siberians are also more cold and heat tolerant.

Siberian irises are mostly hybrids of two southwest Asian species, I. sibirica and I. sanguinea (USDA hardiness zones 3-9). The narrow, grass-like foliage forms a vase-shaped clump to 2 feet high. Autumn foliage turns rusty brown in late fall. Flowering stems rise above the foliage to 3 feet tall in May-June.

Siberians perform well in most garden soils, but are at their best in humus-rich, mildly acidic soil. In spring feed with 10-10-10 or an equivalent granular fertilizer. In early summer apply a water soluble fertilizer such as Miracle-Gro™ or Jack’s™.

In Northern states (zones 3-6), Siberians want full day sun (or 6-hours minimum). In Southern areas, shelter from the mid-afternoon sun. Ample spring moisture is key, along with adequate rainfall during the summer. These iris clumps tolerate moderate summer dry periods of a week or two.

Mulch iris in spring to conserve soil moisture and prevent weed infestation. Voles and mice may munch on rhizomes. Remove spent bloom stalks, and brown and withered leaves to keep planting looking attractive. In late fall cut back all leaves 1-2 inches above the ground.

Siberian irises are generally pest-free with very little susceptibility to the two main problems of bearded iris, namely iris borer and bacterial soft rot. Plants tolerate deer and rabbits.

Divide big healthy clumps into 2-4 fans in either late summer or fall, depending on where you live. In northern zones spring or late summer are the best time to plant or divide. In southern climes, early fall is a better time. Clumps can grow undisturbed for several years, unless they become crowded, plant vigor declines, or bloom size declines.

Over 200 varieties are available, principally from online iris nurseries.

Soil Test Before Planting

Tilled soil ready for planting

Soil testing is your best low cost insurance for enjoying a beautiful garden or lawn through this year and years ahead. In mid-winter, before the rush to spring garden begins, take soil sample(s) to the local Extension office or mail directly to your State University soil lab. 

The local Extension office may charge you a very modest fee, usually $10-12 per sample in most states. Many local garden centers and farm cooperatives may also offer this service.

Within a few weeks a soil analysis report will arrive in the mail. It tells you the current nutrition level and pH of the soil. Also, how much chemical fertilizer, limestone, manure and other organic components to add. For organic farmers and gardeners, inform the soil lab staff that you are growing organically.

This accurate diagnosis will save money. Your garden soil may be rich enough to not need any fertilizer, or too high in certain nutrients, lime or sulfur. The soil pH may be too acidic (below pH 7.0) or alkaline (above pH 7.0). Many garden plants as azaleas, rhododendrons, dwarf conifers and blueberries prefer an acidic pH around 5.0. A soil high in alkalinity (pH above 7.0) could mean that some minor nutrients like iron or manganese may be unavailable to some plants.

How to collect a sample: Test your garden or lawn soil at least once every 4-5 years. You may want to separately test lawn, vegetable, fruit, and flower garden areas. If you specialize in growing roses, test this garden spot separately. For each garden section, randomly collect (dig) 4-5  spots to a depth of 5-6 inches into a bucket. From the bucket mix the sample and collect enough soil to fill a large baby food jar. The soil should be aired dry for several days before mailing it to the soil lab. Label the sample "roses", "vegetables", or "flowers".

Japanese Umbrella Pine

30-year old Specimen at NC Arboretum in Asheville

Japanese Umbrella Pine (Sciadopitys verticillata) is an evergreen (USDA hardiness zones 5b -9). It is not actually a pine and is more closely related to yew (Taxus).  

Historically, umbrella pines date back to the dinosaur age. This mid-sized landscape tree possesses several fine attributes: shiny leaves are arranged in whorls like the spokes of an umbrella; peeling, reddish brown bark and a conical habit.

To conifer collectors, umbrella pine is the premium prize for any private collection. A young tree may require training to develop a strong central leader. Dwarf cultivars (see below)  grow slowly, only 4-5 inches yearly.

Umbrella Pine prefers a moist, organically rich, well-drained, moderately acidic soil. Feed with a slow release organic fertilizer in early spring. Maintain a 2-3 inches layer of an organic mulch around the tree base. In the mid-South (zones 6 -7), the tree prefers one-half to full-day sunlight. Further south,  morning sunlight is preferred. Pruning needs are rare, mostly to maintain the tree's pyramidal form and to remove a broken limb or two in late winter. Disease and insect problems are rare.

In the early years umbrella pine is a slow grower. Eventually, it reaches 30 to 40 feet in height and 20 feet in spread. Well cared for tree forms may attain 70 feet or more in height. This unique conifer possesses stiff needles arranged in whorls resembling an upside-down umbrella. Branches often will withstand heavy snow and ice loads.

The Umbrella Pine is an evergreen prized for its striking foliage and superior pyramidal form. Needles rarely go off color in winter. Select forms are available at specialty conifer nurseries.
Here are four dwarf forms for small gardens:

'Aurea' - yellow needle foliage

‘Gruene Kugel’ - from Germany with a rounded habit when young, slowly develop into a small compact tree with glossy deep green foliage year-round.

‘Joe Kozey’ grows tall and exceptionally narrow at 20 feet high and only 6 feet wide; slow-growing, spire-like habit.

'Picola' - broad growing, 2- inch long dark green needles; ultra-dwarf selection 16- 20 inches tall after 10 years; rock garden plant.

Dwarf Forms Of Elkhorn Cedar (Thujopsis)

Elkhorn cedar (Thujopsis dolobrata) is a slow to moderate growing evergreen shrub or tree. It is also called Hiba or false arborvitae and deerhorn cedar, referring to the shape of its scale-like leaves. It is rarely grown in U.S. gardens (USDA hardiness zones 5-7).

Thujopsis 'Aurea'

This native of Japan and China has a pyramidal growth habit and beautiful dense foliage similar to arbovitae (Thuja spp.). Mature trees may reach 50 -100 feet in height in the Japanese woodlands.  

The scale-like bright or dark green leaves are arranged in flattened sprays with white markings beneath.  Its reddish-brown peeling bark adds to the plant's appeal.  Small 3/4 inch cones provide little ornamental value. 

False arborvitae grows best on a moist well-drained site in full sun or bright shade . Occasional watering is recommended in severe summer/fall dry periods. False arborvitae needs to be sheltered from dry winter winds.

Winter foliage color may vary by location and cultivar planted. Here in the Southern Appalachian Region (USDA zones 6 and 7), winter foliage takes on a muted olive-green tone.

Two dwarf clones are:

• 'Aurea' - a dense shrub with golden yellow foliage; grow in light shade.
• ‘Nana’ - a slow growing, dwarf mounding form with good plant symmetry. Its wintry foliage takes on a silvery tint.

A 10-year old 'Aurea' or 'Nana' thujopsis grows 3 to 4 feet tall and 5 to 6 feet wide. 

False arborvitae is hard to find in the nursery trade, but are available thru e-commerce specialty nurseries.

Vertical Accents Using Boxwoods And Japanese Hollies

'Sky Pencil' Japanese Holly

Boxwoods and hollies are popular landscape evergreen shrubs (USDA hardiness zones 5-8). Both are utilized for low hedging and privacy fencing and some varieties are planted for their architectural accent.  Both shrub groups grow best in moist, slightly acidic, well-drained soil and in full sun to partial shade.

These shrubs are regularly pruned and shearing. Spring pruning should be avoided as it tend to stimulate tender new growth that may be injured or killed by late frosts.

In general, boxwoods tend to be more shade tolerant than hollies. Boxwood is best sited where it is sheltered from strong winds, and protected from full day sun in the winter months. Foliage may also bronze in winter. Carefully remove heavy snow accumulations as quickly as practicable to minimize stem/branch damage ("splaying").

'Dee Runk' boxwood

There are few shrubs that fit into narrow spaces better than 'Dee Runk' boxwood (Buxus sempervirens 'Dee Runk'. It is a better choice than currently popular cultivar 'Graham Blandy', which is seriously troubled by soil root rot diseases, particularly Phytophthora.

'Sky Pencil' Japanese holly (Ilex crenata 'Sky Pencil') exhibits a similar upright (fastigiate) form. Japanese holly demands a well-drained soil, and is very susceptible to several soil root rot diseases including Phytophthora and Pythium.

Both 'Dee Runk' boxwood and 'Sky Pencil' holly grow well in large landscape containers on patios and along downtown streets. Expect mature heights between 8-10 feet.