Saturday, February 10, 2018

Growing Pentas To Attract Pollinating Bees And Butterflies

Want to attract more butterflies to your garden this summer? Pentas (Egyptian starflower) (Pentas lanceolata) is what you should be planting. Pentas are one of the best pollinator-attracting plants around. Flower colors range from red, pale lavender, pink and white. 
Pentas blooms all summer long, even during the hottest weather conditions. The large clusters of star-shaped blooms attract butterflies, bees and an occasional hummingbird. These annual flowers perform well both in garden beds and in large containers. Keep plants deadheaded and remove any spent blooms to encourage constant flowering.

Pentas plants are annuals in most U.S. climates (zone 10 hardy). The overall habit of these plants is neat and compact. If plants get too long and woody, cut them back by one-half and feed them with a water soluble fertilizer such as Miracle-Gro, Jacks™, or Schultz. Tall leggy transplants should be tipped back to develop more branching.

Overall, pentas are very easy to maintain. Newer varieties have improved disease resistance and grow shorter, e.g. more compact in habit. Pentas are troubled by few diseases and should be inspected for insects like aphids (in cool springs) and spider mites (dry hot summer periods).

Pentas prefer to be planted in full sun and in moist, well-drained soil. Pentas will dry out in hot summers and should be irrigated weekly during these times.

Leading cultivar series are Graffiti and Kaleidoscope™ (compact growers); Butterfly, Starla, and Northern Lights (taller growing).

Sunday, January 21, 2018

Winter Blooming Witchhazels

'Primervera' witchhazel at Biltmore Estates, Asheville, NC
Starting in February, hybrid witchhazels from China, Korea and Japan begin flowering. Two of the very best are a Chinese species/cultivar called H. mollis ‘Wisley Supreme’ and a hybrid form called H. x intermedia ‘Westerstede’.

'Wisley Supreme' grows to 8 - 12 feet in height and almost the same in width. Its young branches are very upright. Its pale yellow strap-like flowers are long lasting and sweet smelling upclose. Spring-summer oval leaves posess a blue - green cast, and turn buttery yellow in the fall.

Favorite cultivar 'Westerstede' is a hybrid selection (Japanese (H. japonicum) and Chinese (H. mollis) from Germany. Westerstede bears light yellow 1- inch long ribbon-like flowers which are fragrant. Floral buds begin to open 1 - 2 weeks later than 'Wisley Supreme'. The broad 5 - 6 inch circular green leaves turn a nice buttery yellow in fall. Westerstede summer foliage possesses better leaf spot resistance than one-time favorite ‘Arnold Promise’.

Near the end of the calendar year, the U.S. native witchhazel (H. virginiana) blooms. By that time, most Americans pass by this very tall shrub/small tree with their attention set on Halloween and Thanksgiving.

Witchhazels are easy to grow in an average well-drained moist garden soil and in full sun to light shade.  A slightly acidic pH soil is preferred. Most hybrid witchhazels become tall 20 foot shrubs. Annual spring pruning is warranted to keep this vigorous shrub in check.

Most garden centers do not sell early blooming shrubs, particularly witchhazels, but plants are sold at e-nursery outlets.

Wednesday, October 18, 2017

The Garden Begonia Evolution

Whopper Rose/green leaf
'Big Red Begonia/bronze leaf

Wax begonias (Begonia x semperflorens) are popular summer annuals in flower gardens and containers. Over the last few years new interspecific hybrids have changed how we garden with wax begonias.

Hybrid begonias bloom non-stop for almost six months (mid-May thru October (USDA hardiness zones 6 and 7). Plants stand up to summer heat, humidity, and dry spells, and the foliage stays mostly pest and disease free.

Plants grow vigorously, 18 to 24 inches tall and wide by the late summer/early fall. This means fewer plants to purchase to fill the garden space which will save you money. Space hybrid begonias around 15-18 inches apart depending on which of the three series that you plant.

Hybrids boast larger and showier flowers than the traditional wax begonias. Flower size varies from 2 to 3 inches across. The brightly colored blooms are visited by many kinds of butterflies over the long bloom season. Flowers are self-cleaning and require no deadheading. Plants are compact and well-branched.

Bronze-leaf types grow best in full sun, and green leaf cultivars thrive in partial shade.

Begonias need a well-drained soil with lots of well-rotted compost added. Green leaf types tend to scorch under intense sun.

They perform best with moderate fertility and are not heavy feeders. At spring planting, feed with a slow-release fertilizer such as Osmocote™ 14-14-14 or Nutricote™ 13-13-13. Add 1 to 2 feedings in mid-summer with a water-soluble fertilizer (such as Miracle-Gro®, Schultz®, or Jacks®) southern climates (zones 6-9).

Add 2 to 3 inches of mulch for weed suppression and to conserve soil moisture. Irrigate during extreme dry spells to maintain plant vigor, and flower numbers.

Intersspecific Hybrids Begonia Cultivars:

Big™ series are available in bronze-leaf (full sun) and green leaf (part sun) forms; flower color choices are red, rose and pink.

Whopper™  series come in red and rose colors only and are available in bronze-leaf and green leaf types. Whopper plants tend to grow 20-25% larger than Big.

Megawatt™ series. Current varieties include 'Red Green Leaf', 'Pink Bronze Leaf', 'Rose Green Leaf', 'Red Bronze Leaf' and 'Rose Bronze Leaf'; new color choices will be added in 2018.

Saturday, September 16, 2017

'Bluebird' Aster A Top Coice In Mt. Cuba Evaluation Trial

Bluebird aster (Symphyotrichum leave 'Bluebird') is a top selection of U.S. native smooth aster. Bluebird was found in 1988 in a Guilford, Connecticut garden and introduced by Dr. Richard Lighty who at the time was working at Mt. Cuba Center in Greenville, DE in 1994. This tall, vase-shaped wildflower produces large 1 inch wide violet blue flowers on 3-4 feet tall stems. It has attractive, slightly glossy, blue-green foliage that is highly disease- and pest-free.

Bluebird smooth aster thrives in full sun to light shade with a broad tolerance of soil types and moisture levels. Bluebird aster will grow and bloom in part shade, but flower count will be less. In 2016 Bluebird aster was ranked as the #1 aster in an evaluation study at Mt. Cuba Center.

Spring-summer care tip: Prune off old growth from last fall and feed with 10-10-10 or equivalent granular fertilizer. Supplement with water-soluble Miracle-Gro once in mid-summer. Pinch back the young shoots in June for develop a dense plant habit and more flower buds. If left alone, the plant gets too tall and require staking in late summer as flower buds are setting up.
Bluebird aster is a great nectar source for migrating monarch and other late season butterflies.

Sunday, March 6, 2011

'Misty Blue' White Baneberry is Doll's Eye

Discovered at MT. Cuba Center in Delaware is a striking mult-stemmed woodland perennial with soft bluish-green finely cut foliage. Plants flower white in April snd white doll's eye fruit form in the fall. The snow white berries are clustered on bright red pedicels. Each is marked with a distinctive black dot. Fruit persists for 4-6 weeks. This long-lived perennial thrives in moist, well-drained, rich woodland soil. Plants grow 2-3 feet tall and are best grouped en masse. Actaea is reliably hardy through USDA zones 3-8

Thursday, March 3, 2011

Pruning Hydrangeas

Photo: Hydrangea paniculata 'Limelight'

PeeGee or panicled hydrangea (Hydrangea paniculata) or the native Smooth hydrangea (Hydrangea arborescens) are pruned in early spring because they bloom on the current season’s wood. If you feel the need, these plants could be cut to about 4 inches from the ground in early spring and will produce new shoots and blooms during the season.

Sunday, October 10, 2010

New Website at!

I've been working on my new website, What Grows There and have moved this blog over to that location. All new posts will be there. Enjoy!