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 whatgrowsthere.com!

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! http://www.whatgrowsthere.com

Saturday, October 9, 2010

New Intersectional Peonies Deserve A Wow!

Photo: tree peony at Staten Island Botanical Gardens
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.

Wednesday, October 6, 2010

Tips on Planting Peonies

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.

Sunday, October 3, 2010

Goldenrod --Set Off Some Fireworks This Fall

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 show starting in mid-August and lasting thru 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. Surprisingly, goldenrod tends to grow weak lateral shoots in soils that are organically rich.

'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 – 2.5 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.