Pruning Time For Oakleaf Hydrangeas

Native oakleaf hydrangeas (Hydrangea quercifolia) are pruned as their summer flowers start to declines in quality around late July. The main pruning time for oakleaf hydrangeas is from mid-June thru mid-August. At this time, make the big cuts to reduce shrub height and width, if needed. Secondly, remove or “deadhead” all withered or faded flowers.

A frequently asked question is "should I prune my oakleaf hydrangeas coming out of winter"? My general response is no, because you will be reducing the flower count in June. However, if you missed making last summer's cutbacks (or cleanups), you may remove 20-25% of the dormant branches and only sacrifice a few flowers. Broken, diseased wood, plus bottom suckers may be removed to improve the appearance of the overall plant.

Oakleaf hydrangeas set their flower buds for next spring on both old or current season’s growth on the terminal bud. Do not practice pruning in the fall as it may stimulate new soft growth which dies over a cold winter. Make all cuts 1/4 inch above the last set of leaves or cutback flush to a main branch.

Summer pruning improves the health of oakleaf hydrangeas and stimulates new vegetative growth. On older 4-5 year old hydrangeas, remove larger, thicker canes and prune them at the base of the stem.

What about old neglected oakleaf hydrangeas? Remove one-quarter to one-third of these older branches. In 3-4 years the shrub will be completely rejuvenated.

Dead, dying, diseased stems, and old flower heads can be removed at any time of year.

Silberlocke Korean Fir

Dwarf cultivars of Korean firs (Abies koreana) are favorites among many conifer collectors (USDA hardiness zones 5-8). Four ultra-dwarf varieties grow inches per year. Horstmann’s Silberlocke’ is the leading Korean fir variety among conifer collectors. To encourage a deep extensive root system, extra care (TLC) is needed the first 2-3 years after planting in the garden.


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Abies koreana  'Horstmann’s Silberlocke’

'Horstmann’s Silberlocke’ The German word silberlocke means "silver locks of hair". The needles on the branches curl on the tops exposing the white underside of the needles, resulting in a frosted look. Annual growth rate is 6 - 8 inches (15 – 20 cm). Over the years, 'Horstmann's Silberlocke' will develop into a small 12 feet high x 8 feet wide landscape tree. The curling needle trait is often lost as the plant age. ‘Silberlocke’ also produces purple/tan cones on young plants.

Plant in a humus-rich, acidic, well-drained soil and in a sun to partial shade garden bed. Mulch with acidic organic compost such as pine needles, shredded pine bark, or chips. Irrigate once or twice monthly during periods of drought, heat or high winds.


Korean fir appears to be more heat tolerant than other firs, but it prefers cooler regions of the U.S. As with most firs in the South, Korean fir will often fail if too hot and will fail in wet soppy soils. In the warm humid southeastern U.S. environment, Korean fir should be grafted on Momi fir (Abies firma) rootstock. Dwarf forms make great additions to a small urban garden, a rockery, or a large container. Korean fir is rated as deer resistant.


Because of their rates of growth, super dwarfs are investments in the future. A plant with some size will likely command a premium price.

List Of Weeping Tree Forms

The following is a list of currently 26 species of landscape trees which lists one or more weeping cultivars. over time, more tree genera will be added:

Weeping willow (Salix)

• Weeping Japanese Maples (Acer palmatum) –‘Ryusen’, 'Matsukake', 'Omuyarama' and 'Green Cascade' among others

• Weeping river birch (Betula nigra ‘Summer Cascade™’)
• Weeping birch (Betula pendula) 'Youngii’, 'Dalecarlica', 'Golden Cloud', 'Gracilis', 'Laciniata', 'Purpurea')
• Weeping katsura tree (Cercidiphyllum japonicum) 'Pendula', 'Tidal Wave', 'Amazing Grace'
• Weeping redbud (Cercis canadensis) ‘Traveller’, ‘Ruby Falls’, Lavender Twist® (‘Covey’), ‘Whitewater'
• Weeping Blue Atlas cedar (Cedrus atlantica) ‘Pendula’

Weeping mulberry (Morus)

• Weeping Himalayan cedar (Cedrus deodara ‘Pendula’)
• Weeping beech (Fagus sylvatica 'Pendula', 'Atropunicea', 'Atropurpurea', ‘Purpurea Pendula’
• Weeping Japanese Larch (Larix kaempferi 'Pendula')
• Weeping crabapple (Malus x ) ‘Red Jade’, 'Louisa', 'Luwick', Molten Lava™ (‘Molazam’), 'Royal Fountain', several others
• Weeping white mulberry (Morus alba ‘Pendula’ (female clone –sets fruits); 'Chaparral’ (male clone – no fruits)
• Weeping blackgum (Nyssa sylvatica) ‘Autumn Cascade’
• Weeping Norway spruce (Picea abies ‘Pendula’)
• Weeping Serbian spruce (Picea omorika ‘Pendula)
• Weeping white pine (Pinus strobus ‘Pendula)
• Weeping Flowering Apricot (Prunus mume 'Pendula')
• Weeping cherries (Prunus serrulata 'Kiku-shidare-zakura')
• Weeping Higan cherry (Prunus subhirtella 'Pendula', 'Pendula Alba', and 'Pendula Rubra')
• Yoshino cherry (Prunus x yedoensis ‘Snow Fountains’)

• Weeping willow (Salix spp.) – many weeping cultivars; Contorted leaf willow (Salix matsudana 'Tortuosa')
• Weeping Japanese snowbell (Styrax japonicus) ‘Fragrant Fountains’, ‘Marley’s Pink Parasol® (‘JL Weeping’); Carillon’
  
• Japanese Pagoda Tree (Styphnolobium japonicum 'Pendula')
• Bald cypress (Taxodium distichum) – ‘Cascade Falls’, ‘Falling Waters’ (both grafted shrub forms that may be trained into small weeping tree forms)
• Little leaf linden (Tilia cordata) - 'Pendula Nana' and 'Girard's Pendula Nana' (both are dwarf forms)
• Weeping Silver Linden (Tilia petiolaris ‘Pendula
• Canadian hemlock (Tsuga canadensis) ‘Pendula’ –several weeping shrub forms
• Camperdown elm (Ulmus glabra 'Camperdownii')
• Weeping Alaskan cedar (Xanthocyparis nootkatensis 'Pendula', ‘Jubilee’, ‘Strict Weeping’)

New Osage Orange Trees Are Gamechangers

Osage Orange replaced with thornless, fruitless varieties

Osage orange (Maclura pomifera) has been declawed and neutered (USDA Zones 5-9). A member of the mulberry family (Moraceae), this tough prairie tree species is native to south Central states. The medium-sized 35-40 foot tree grows fast @ 2 ½ to 3 feet per year. It is also called Bois D’Arc (pronounced “bow-dark”).

‘Wichita’ and ‘White Shield’ are fruitless and thornless (male) selections. Both cultivars develop into attractive landscape trees with deep green shiny foliage that turns a beautiful fall pale to golden yellow in fall. ‘Wichita’ grows slightly taller than ‘White Shield’, and its branching is slightly more upright.  ‘White Shield’ forms a rounded canopy, averaging 35 feet in height and spread.  Mostly inconspicuous tiny green flower clusters appear in late spring.

Osage orange, aka "hedge apple" is a dioecious species. Male trees make effective landscape shade trees. Female trees are generally not recommended for landscape use because their fruits pose a considerable litter problem. Mature tree bark is deeply fissured, with an orange-brown inner wood peeking through. In the early years, pruning helps to develop a well-branched tree.

Hedge apples, i.e. large 4-6 inch wide yellowish green fruit, weigh 2 to 3 pounds each. Fruits on female trees fall from the tree in October and are a huge maintenance headache. Female trees need a male tree pollinator in order to produce fruit.

Fierce ½- inch long thorns, hidden within the dense branches, can do lots of harm, even puncture a vehicle tire. The tree’s wood is hard and does not split easily.

Osage orange is easily grown in average, dry to medium, well-drained soils in full sun to part shade. The tree grows almost anywhere, in poor infertile, acid or alkaline soils, and dry or wet fields. It also tolerates drought, heat, cold and wind. Disease and pest problems are practically non-existent. Its foliage is tolerant of urban air pollutants.

Both cultivars are good choices planted on large residential or commercial properties, city parks, and golf courses. Also, plant under high power lines or utilize as a deciduous windbreak.

Red Dragon™ Contorted Filbert

Red Dragon filbert in Columbus, Ohio garden

Red Dragon™ is an outstanding red leaf selection of contorted filbert (C. avellana Red Dragon™). This unique landscape shrub grows 6 - 8 feet tall and 5 - 6 feet wide. It is a perfect size for most urban gardens (USDA hardiness zones 4-8).

This red-leaf shrub was developed by the Oregon State University filbert breeding program. Currently, gardeners are losing the popular green leaf variety "Harry Lauder’s Walking Stick" (C. avellana ‘Contorta’) to Eastern filbert blight. Red Dragon filbert demonstrates superior resistance to this disease. It also replaces ‘Red Majestic’, another red leaf variety also susceptible to Eastern filbert blight.

Red Dragon grows best in moist, organically rich, well-drained soil and in full sun to partial shade. It tolerates average garden soils. Prompt removal of root suckers improves shrub appearance by avoiding a buildup of thickets.

Autumn leaf drop exposes the unique contorted branching and ornate floral catkins in early days of spring. Filberts are monoecious, e.g. individual male and female catkins (flowers) develop on the same plant in late winter to early days of spring (March-April) before leaves emerge. The 2-3 inch long yellow male catkins (flowers) are showier. The 4-inch elliptical or ovate leaves are doubly serrate.

Red Dragon retains its burgundy red leaf color into early summer. The foliage is also partly curled. Leaves are coated with tiny hairs and appear dusty by the end of summer. Fall leaf color is variable, often with tinges of yellow. Smooth light bark is gray-brown.

Nuts appear in terminal clusters of 1-4 and are half covered in ragged husks. Nuts ripen in late August and September which the neighborhood squirrels and birds should enjoy.

Red Dragon filbert may also be grown in containers. Disease and pest problems are few. Japanese beetles may vigorously attack the foliage in some areas. Scale may also occur.

Red Dragon™ is mostly sold grafted and available from specialty nurseries online. It requires little to no pruning; remove root suckers and keep the shrub well mulched. ‘Red Dragon’ is sold either grafted or not. It is sold primarily by online nurseries.

Small Leaved Anise

'Florida Sunshine' anise at Milliken Arboretum in Spartanburg, SC

In recent years there has been lots of interest in the anise (Illicium) shrub group. Anise shrubs (Illicium spp.) are fast growing, evergreen shrubs (USDA zones 7 to 10). They exhibit a multi-stemmed, upright, compact form. Their green foliage  is quite attractive and aromatic, the odor similar to anise spice when crushed. Their shiny, leathery leaves are olive green in color and the 1.5 inch wide flowers are dark red and appear in early spring.

Yellow anise (Illicium parvifolium), aka small anise, is a Southeast U.S. native. Popularity has soared with the introduction of gold leaf cultivars like 'Florida Sunshine' and Banana Appeal®. The cultivar 'Florida Sunshine' grows only 7-8 feet tall. Both cultivars are more tolerant of full day sun and dry soils. Their gold color becomes sharper over the winter months

In the wild, species shrubs eventually grow 10 to 15 feet tall and should be spaced at least 5-6 feet apart in the landscape. Their natural habitat is in the wet, swampy areas or along wooded streams in humus-rich  acidic soil from Florida to Louisiana. However, newer varieties have demonstrated winter hardiness further north into (zone 6) parts of Tennessee, Carolinas, and Virginia.

Illicium grows in partial to full shade, but reportedly will acclimate to full sun if irrigated. The anise shrub world is changing. Watch for new cultivars arriving at local garden centers.

Kentucky Coffeetree

Kentucky coffeetree (Gymnocladus dioicus) is a large native tree found in 18 states, from New York west to Nebraska and from central Minnesota south to Oklahoma (zones 4 through 7). It averages a mature height between 60- 70 feet (some greater than 90 feet) with a spread of 35-50 feet. This tap-rooted tree establishes within 2-3 years, with an annual growth rate averaging 12-15 inches, about the same as ginkgo or white oak.

Kentucky coffeetree

Spring leaf out occurs in mid- to late spring. Recessed vegetative buds push forth as multi-pinnate compound leaves. A single leaf may measure 2 to 3 feet across, producing between 70 and 100 leaflets. Fragrant olive-white flower panicles appear in late May in clusters of 8 to 12 inches long by 3 to 4 inches wide.

In autumn its lime-yellow to golden brown compound leaves drop to become a leaf raker’s nightmare. During the winter months, the totally naked upright branches take on a stark appearance. K-coffeetree may be single or multi-trunked.

K-coffeetree grows in a wide variety of soil types and tolerates a poorly drained wet sites. No significant disease or insect pests mar the lush green tropical-like summer foliage. Bark is distinctively charcoal gray and shaggy, a trait more pronounced as the tree ages.

Spring pea-like flowers are dioecious, bearing either male or female flowers. Female trees bear clusters of broad bean pods measuring 5 -10 inches long and 1 ½ - 2 inches wide on the tips of branches. Flowers and pods are inconspicuous, mostly hidden within the dense foliage through late summer.

'Espresso' is a male cultivar with no seed pods to rake up. In colonial America the beans were harvested and a crude coffee extract was brewed, no threat to Starbucks. The leaves and bean seeds are reportedly toxic to man and grazing cattle.

K-coffeetree is rarely sold in garden centers, but is available from on-line nurseries. Notoriously difficult to transplant, young 2-inch caliper nursery-grown trees move easily.