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.

July/August Blooming Plumleaf Azaleas

July/August Blooming Plumleaf Azalea

Plumleaf azalea (Rhododendron prunifolium) is a deciduous azalea that is native to  Georgia and Alabama mountains (USDA hardiness zones 6-9). It is one of the signature plants of Callaway Gardens in Pine Mountain, Georgia.

Their bright orange-red flowers surprise in late July into early Augusta and may last for 2 weeks or more. Compared to many other spring blooming native azaleas, flowers are not fragrant. Spring and summer foliage is medium-green and is mostly blemish-free.

Fall leaf color is also uneventful. Insect and disease problems are rare if the plant is properly sited. 

This 5-8 feet tall and wide shrub performs best in morning sunlight and shaded from the harsh afternoon summer sun. It thrives in well-drained, compost amended soil. Plumleaf azalea prospers in the calcareous clay soils found in the Appalachian region without pH correction.  Plant in full-day light shade in zones 7-9. Set the shrub into a shallow wide dug hole that has been generously amended with compost and/or peat.

Feed in early spring with a slow-release fertilizer such as Osmocote™ or Nutricote™. An alternative nutrition program is to use a water soluble product such as Miracle-Gro™ or Jack's™  in early spring and again in early summer. Maintain 2-3 inches of a pine-based mulch around the base of the shrub. Irrigate plant(s) the first 2 years of establishment.

Plumleaf azalea blooms on new current season's wood. Prune deciduous azaleas anytime after bloom to maintain a desired height and spread. Plumleaf azalea is primarily available at local native plant nurseries or is offered online.

Plumleaf azaleas are usually available from mail order companies on-line.

Keep Your Eye on Red Buckeye

Spring blooming Red buckeye

Red buckeye (Aesculus pavia) is a large shrub or low branched tree maturing to a 15 - 20 feet in height and spread. This southeastern U. S. native is becoming more recognized as a good selection in small urban landscapes.

The red buckeye tree flowers young, either in full or partial sun. Numerous 5- to 9- inch long floral heads sit at the ends of branches like decorative candles in late April and May. Flowers open just before the leaves begin to emerge. Flower color on individual trees varies from dark pink to scarlet red. A yellow flowering form is known to exist. Hummingbirds arrive to pollinate the individual funnel-shaped blossoms.

Lovely dark green, palmate compound leaves clothe the branches in the spring and early summer months. The polished dark buckeye seeds fall from the tree beginning in late September, quickly grabbed up by squirrels and others. Seeds are poisonous.

Disease and insect problems are of little consequence in the spring and early summer months. Disease blotched foliage that may also be scorched on the edges, the result of dry summers, results in a premature leaf drop by late August and September. Expect little to no autumn foliage color as branches are typically bare.

Carolina All-Spice Sweetshrub Or Bubbybush

What's in a name? Sweetshrub (Calycanthus floridus) is one of our finest native shrubs. Its waxy, reddish brown flowers emit an enticing fruity fragrance. The 2" wide flowers bloom starting in late April, and sporadically June through August.

Many gardeners in the southern Appalachians (plant hardiness zone 6 -8) call it “bubbybush” or “sweet bubby”. In the 1800's, long before deodorants, women used the fragrant flower as a perfume to mask body odor. They would hide the tough, almost indestructible flowers under their dresses, in their pockets, even pin them on their clothes.

Sweet shrub is easy to grow. Plant in fertile, well-drained garden soil and in sunny to partly shaded landscape. It flowers best in full sun and stay dense and tight. The beautiful deep green leaves measure 5-6" long, ovate, and exhibit a nice yellow fall color and persist into November. The large, 'urn-shaped' fruits mature in October.

The cultivar ‘Athens’ has yellow fragrant flowers. New Asian/American hybrids from the North Carolina State University’s plant breeding program are ‘Hartledge Wine’ (red, non-fragrant flowers) and most recent introduction ‘Venus’ (creamy white, fragrant flowers).