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

Arkansas Bluestar Great In Spring, Summer and Fall

Posted by Hugh on October 27th, 2010

Blue star (Amsonia hubrichtii) exhibits one of nature’s finest autumn foliar displays. This Arkansas native is a long-lived perennial and prospers here in the Southern Appalachian region (USDA zones 6 and 7). After its initial year in the garden, amsonia exhibits good heat and drought tolerances.

Its fine textured needle -like foliage is very soft and airy. In the fall the foliage turns a stunning golden yellow and makes a lovely backdrop among other fall flowering perennials, such as asters and mums. Amsonia’s fall color stands apart against a background of tall evergreens.

In late spring (May) small light blue flowers open in abundance. Amsonia thrives in most soils and requires little maintenance throughout the year. Plants grow 3 ft. tall by 3 ft. wide and grow best in full or part sun. Stems tend to flop in shady areas. To maintain shorter more compact plants, prune them back to 6-8 inch height after flowering.

Arkansas blue star was selected the 2011 Perennial Plant of the Year by the Perennial Plant Association.

Ginkgo -Sex Education 101

Posted by Hugh on October 22nd, 2010

“Apricot-like” Fruits On Female Ginkgo

Surviving an autumn season with a heavily fruited ginkgo (Ginkgo biloba) tree is a foul smelling experience. The odorous yellow fleshy fruits ripen in October and drop onto public streets and home lawns. Several times I have witnessed the Jonesborough Tennessee Fire Department raking up fallen fruit and hosing down a sidewalk too treacherous to walk upon from the slick pulp that coated the street. Attempting to remove the stench from your shoes is an almost impossible task.

Ginkgo is a lovely large shade tree which prospers over many human generations in the landscape (USDA hardiness zone 4-8). The dioecous (single sexed) ginkgo tree is either male or female. In many U.S cities, a female ginkgo is forbidden by law to be planted. Most nurseries sell male-grafted trees, properly labeled by cultivar. Some recommended selections are: Princeton Sentry®, ‘Magyar’, ‘Fairmount’, ‘Haika’, ‘Autumn Gold’ and Spring Grove®.

Gardeners may harvest the fruit, remove the pulp and sow the seed in the fall. The following spring many seeds germinate and develop into lovely ginkgo trees if properly pruned, irrigated and fertilized. A lingering question is whether the tree seedlings are male or female. Ginkgo grows into flowering adulthood in 20-25 years. Worth the wait or do some trees become a chain saw disappointments?

Plant Lovely Camassia for the Spring Garden

Posted by Hugh on October 18th, 2010

Camassia is native to the mountains and prairies of western North America, where it is called Indian quamash. In earlier times several native North Americans tribes commonly cooked this edible bulb, particularly of species C. quamash.

Camassia tolerates moist wet soils. It may be planted along the edges of ponds or in the front of a low garden border. Tall spikes of starry-shaped blooms appear in mid-to late-spring. From mid- to late spring camassia blooms well either in full sun or partial shade in the Southern Appalachian region (USDA zones 6 and 7).

Camassia mixes well with other spring and summer perennials, including low ground covers. Overcowded bulbs should be dug up in early fall, divided and replanted. Three noteworthy species are:

Camassia cusickii bearslight blue flowers in May-June. Plant grows 24-32 inches high. Bloom spikes are adorned with multitudinous small star-shaped flowers.
C. quamash (formerly C. esculenta) produces shorter (14-16 inches tall). Deep blue flowers bloom slightly later than the other two species.
C. leichtlinii boasts creamy white flowers that bloom in April and May. Cultivars grow an average of 24-40 inches tall. Flower color varies with ‘Alba’ blooming pure white and ‘Caerulea’ light blue. ‘Sacajawea’ has creamy edged, variegated foliage and white flowers.

Find camassia for sale at leading on-line bulb emporiums such as brentand becky’sbulbs.com and brecks.com

Gather Acorns To Become Mighty Oaks

Posted by Hugh on October 16th, 2010

Several species of oaks (Quercus spp.) make their home here in the Southern Appalachian region (USDA zones 6 and 7). Every 3 – 5 years, a majestic oak bears a heavy crop of acorns. Squirrels and gardeners gather acorns (seeds) to plant oaks for future generations.

Oaks are divided into two groups. White, swamp, and bur oaks, with rounded non-bristly lobed leaves, comprise the white oak group. From August thru December these acorns germinate within a few weeks after falling to the ground.

The black oak group includes red, pin, shingle and willow oaks. Leaves possess one or more pointed bristled lobes. Acorns do not germinate until spring.

Acorn survival is low unless planted in the soil. Gather up freshly fallen ripe (brown) acorns. Dispose of all which are discolored, have tiny holes (from weevils), or are exceptionally small in size.

Gather and sow acorns in the fall. Prepare a planting bed or nursery row and sow acorns 1 – 2 inches deep and 6 – 12 inches apart. After 18 – 24 months, transplant small tree seedlings to a wider 3 – 5 foot spacing to grow on for another 1 – 2 years. Maintain weed free beds, and fertilize and irrigate for maximum growth.

While slow at the start, nurturing a young oak tree grows to be rewarding for you and future generations.

Deadline Approaching for Seeding/Renovating Lawns

Posted by Hugh on October 12th, 2010

Early fall is the “spring-time” for establishing a new lawn or renovating a tired weed infested turf. In the fall most of the weed infestation, particularly from annual pest grasses like crab and goose-grasses, is over.

You have another week (until October 20th) to wind up this chore. To completely seed a sunny area, choose a quality blend (two or more varieties) of tall fescue at a seeding rate of 6-8 lbs. per 1000 square feet of lawn area. Over a partially shaded area seed in red or chewings fescue @ 2-3 lbs. per 1000 square feet.

Use less than half the seeding rate over patch or renovated areas.

October is a traditionally dry month (appears to be the same this year as well here in the Southern Appalachian region (USDA zones 6 and 7). Days and soil temps are still warm and the new lawn seeding will germinate rapidly. Irrigate lightly, (termed “spritzing”), the newly seeded areas 1-2 times daily. Spread one bale of hay per 1000 square feet over the newly seeded lawn area to reduce daily irrigation and distract birds from dining off your future lawn.

In early November feed with a winterizing 2 -1 -1 ratio of lawn fertilizer, following package directions. Mowing height can be lowered to 1 1/2 inches and a mulching attachment to the mower blade will grind up fallen leaves and debris into mulch.

New Intersectional Peonies Deserve A Wow!

Posted by Hugh on October 9th, 2010

Itoh or Intersectional Hybrid Peonies (Paeonia spp.) represent a huge breakthrough in tissue culture propagation. Inherited from the tree peony is attractive dissected foliage. They are extremely winter hardy like the herbaceous types.

Plants grow two to three feet tall and wide. Strong sturdy stems support the huge flowers which size up to 10″ across. Flowers are single, semi-double or double, and available in a wide range of colors including yellow. Flowers stand upright even in heavy rain and require no staking. Bloom time is longer due to additional flowers being produced on side shoots.

Peonies are long-lived, growing in the same location for decades. They need to be properly nourished annually. Peonies prefer full to part sun (minimum of 6 hours per day), average moisture and well-drained soil which is enriched with compost or mulch annually.

Bare-root peonies should only be planted in the fall as this coincides with the time that their tubers develop most of their feeder roots. Container-grown peonies can be planted at any time. Itoh hybrids demonstrate good resistance to peony blight (Botrytis paeoniae).

Proper planting depth is very important for peonies. The crown should be planted 1½ – 2 inches below soil level. If the eyes have already begun to grow, the new growth may be set slightly above the surface.

Itoh peonies are now available through e-commerce nurseries.

Tips on Planting Peonies

Posted by Hugh on October 6th, 2010

Peonies (herbaceous types) are old-fashioned perennial favorites garnering new attention from 21st century gardeners. Their gorgeous spring flowers stand tall above the lush shrubbery growth.

This fall, plant dormant bare-root divisions of herbaceous peonies purchased from a mail-order nursery or a nearby garden center. Each division must exhibit 3 to 5 eyes (buds). Space plants a minimum of three feet apart.

Good air circulation around plants is important to prevent potential foliar and flower diseases. Avoid windy areas and shelter plants from harsh summer sun and heat in warmer climates (USDA zones 7-9).

Peonies thrive in gardens for 20 or more years. Select a sunny spot with well-drained garden soil and enrich with generous amounts of compost or well-rotted manure. A soil pH between 6 and 7 is ideal. Feed peonies with a slow release fertilizer in early spring the same as you would nourish flowering shrubs.

A critical digging step is the planting depth. Do not cover the growing eyes with more than 1 inch of soil. Setting the new plant too deep may delay or even prevent flowering. Water the newly planted peonies and cover the bed with 2-3 inches of loose ground up leaves or bark mulch. Likely, the peonies will bloom next spring and many years thereafter.

Tree peony culture will be discussed in a future blog.

Goldenrod –Set Off Some Fireworks This Fall

Posted by Hugh on October 6th, 2010

Rough-stemmed goldenrod (Solidago rugosa) grows in low woods, meadows and bogs in the eastern half of North America. ‘Fireworks’ (USDA zones 4–8) has a more compact plant habit than the species. This early blooming cultivar provides a long floral display starting in mid-August and lasting through Thanksgiving, weather permitting.

Flowers spikes are numerous and held in tight clusters on upright stems. The yellow, thread-like, cascading sprays of flowers do attracts many insect pollinators; the pollen does not cause allergies as once believed.

Goldenrods grow best in full sun to light shade. While they prefer moist, well-drained, slightly acidic soil, established plants flourish in hot, humid and dry summers.

‘Fireworks’ spreads quickly by seed and underground rhizomes and needs to be divide every 2-3 years . This upright herbaceous perennial grows 3 – 4 feet tall and 2 – 2 1/2 feet wide. Remove old flowers to encourage re-blooming. Deadhead or remove spent blooms on ‘Fireworks’ to generate added lateral floral sprays into late October and November. Removal of seed heads reduces re-seeding threat.

Clipping plants back in mid-June by one-half creates a better, well- branched plant, increases bloom head size, and reduces the need of re-staking.

Fall Planting Deadline for Pansies and Violas

Posted by Hugh on September 30th, 2010

To grow pansies successfully, follow this four- step program. Start with:

Purchasing healthy plants
Planting by mid-October or earlier
Watering in the fall and winter as needed
Fertilizing monthly through the winter and spring months.

Shop for vigorous dark green plants at local greenhouses and garden centers. Closely inspect for lots of white growing roots. Don’t buy short or spindly seedlings or those with yellowing leaves. Purchase sturdy 1801 plants (18 – 3 ½” plant cells per tray) or larger pots. Small pansies tend to be more disease susceptible. To avoid deadly root rot diseases in garden soils, move pansy/viola beds every three years.

Over much of the Southern Appalachian region (USDA zones 6-7), the completion date for planting pansies and violas is October 15th. Back up a week or two earlier if planting in gardens at higher elevations. An earlier fall planting date allows plants adequate time to root down into the warm autumn soil. Deeply rooted plants bloom heavier through the fall and winter seasons.

Large sized plants start off quickly and fall-winter flowering is better. Deeply rooted pansies and violas provide better anchorage, which prevents a chance of winter freeze heaving. Once soil temperatures drop below 45°F, plant growth slows and flower numbers decline.

There are many series of pansies and violas to choose in colors ranging from white, yellow, pink, red, and purple shades. Color patterns may be clear, blotched or picotee. Four popular pansy series are Delta®, Matrix®, Panola®, and Majestic Giant ll™. Among the popular viola series are Sorbet®, Rocky™, Penny™ and Velour™.

Prepare the garden bed or containers prior to planting. Pansies should be planted in well-drained, organically rich garden soil or container media mix. An acidic soil pH ranging between 5.2 – 5.8 avoids natural deficiencies in iron and manganese. Adding lime to pansy beds is usually unnecessary unless recommended after a soil test. Pansies thrive in full sun to partial shade. Plants grow more compact and bloom heaviest in full sun.

Franklinia – Native Tree Lost in the Wild

Posted by Hugh on September 27th, 2010

Franklinia (Franklinia alatamaha) is a wonderful small tree or large multi-trunked shrub with fragrant white camellia- like flowers. Franklinia is related to world-class flowering shrubs like camellia and stewartia. Its white 3 – 3 ½ inch camellia-like flowers appear from early August thru late September.

Franklinia is winter hardy in the Southern Appalachian region (USDA zones 6-7). Its fibrous root system prefers a well-drained, richly organic, and acidic soil much like azaleas and rhododendrons. Don’t subject to extended summer droughts or frigid drying winter winds.

Fall color is respectable with autumnal hues of red, orange and burgundy. The bark on a young tree is distinctively striped, and the main branches become fissured with age.

The species was discovered by plant explorer John Bartram and his son William growing along the Alatamaha River in southeastern Georgia in 1765. Natural populations are now extinct. All franklinia trees growing today are descendants of the Bartrams’ collected seeds.

Franklinia is a finicky grower, but very much worth the challenge. A deadly fungal root disease, Phytophthora cinnamoni, may have led to its demise in nature, is its Achilles’ heel. A 2-3 week long invasion of Japanese beetles in August may shorten individual bloom life by half.