Last week’s unprecedented cool days and wonderfully mild cool nights have set the stage for a fine fall foliage event. In our Rock & Waterfall (shade) Garden the fall colors are as good as ever. I expect peak fall color out here at Powell Gardens this weekend, one week earlier than “average.”
Weeping Threadleaf Japanese Maple (Acer palmatum dissectum group ‘Viridis’) has fall color that appears on fire in the shaded understory of the Rock & Waterfall Garden. The finely cut leaves add a very fine texture in contrast to larger coarser leaves of wild oaks.
The Redwing cultivar of American Highbush Cranberry (Viburnum trilobum ‘Redwing‘) reveals a very complex range of colors that is quite wonderful. This shrub is native in the Great Lakes States and northeast and prefers a cool, afternoon shaded environment here. This plant is in full shade so did not flower or produce its classic red fruit for the winter landscape, but its foliage has been exceptional all season.
A different cultivar of Threadleaf Japanese Maple ‘Emerald Green’ shows orange fall color. Again, the delicately dissected leaves add a very fine texture, even finer than ferns in the foreground.
This small tree is a fun challenge on identification. The leaves look like an elm or hornbeam but they are opposite each other on the twig. This is actually a maple species from Japan! Hornbeam Maple (Acer carpinifolium) reliably turns nice yellow hues in fall in a shaded understory environment as seen here in the Rock & Waterfall Garden.
The Rock & Waterfall Garden is known for its azaleas and hybridizers have created a new series that rebloom well into fall! These azaleas are known as Encore (registered trademark) Azaleas and this is the cultivar ‘Autumn Royalty.’ These azaleas are listed as hardy only through zone 7 but they have done well in sheltered locations in the recent mild winters. This shrub was donated to us by Leah Berg — she also hosted a recent program with Fox 4’s meteorologist Don Harman. Don showed us that statistics document the average winter temperature for Greater Kansas City has increased by 6 degrees F over the past 30 years.
One of my favorite shrubs Oakleaf Hydrangea (Hydrangea quercifolia) reveals a very complex pattern of fall colors emerging on its leaves when grown in sun. There are two or more weeks of good fall color on this shrub as long as temperature don’t plummet too low.
The Winterthur (pronounced winter-ter) cultivar of Witherod Viburnum (Viburnum nudum) has spectacular fall color — starting out purple then turning this bronzy red as the green chlorophyll is withdrawn from the leaves. The leaves are also glossy which adds to this color display and here at the entrance to bridge to the Island Garden, it is masterfully combined with a bronzy-orange Andrea mum.
The Island Garden’s Senior Gardener Mark Gawron planted this Mum (Chrysanthemum x morifolium ‘Andrea’ — not accessioned because we didn’t expect it to return) for seasonal color in the fall of 2006 and it has weathered 2 winters now and is a most masterful combination with the Winterthur Viburnum in a area whose color scheme is orange, burgundy and pink.
Female cultivars of American Bittersweet (Celastrus scandens) grace the railings of the bridge to the Island Garden and are in fall color and full fruit display. A male and female vine are needed together to set fruit. For those who want just ONE bittersweet I am happy to let you know a new cultivar that is self-fruitful in now available! Look for the Bittersweet ‘First Editions (registered trademark) Autumn Revolution (trademarked)’ at local nurseries that carry Bailey Nursery plants.
‘Tis the season for one of my favorite perennials: Hillside Sheffield Pink Mum (Chrysanthemum coreanum hybrid ‘Single Apricot’) Each late fall I thrill at the magnificent floral display of this reliably hardy mum (now blooming for the 9th straight year at this location on the Island Garden). Anyone with a butterfly garden should include this plant as it is the favorite last nectar source of many butterflies and beneficial insects.
The Living Wall on the Island Garden still has stunning compositions of plants: here blue-flowering ‘Walkers Low’ Catmint (Nepeta x faassenii) is underplanted with stunning Furman’s Red Autumn Sage (Salvia greggii). Both these are very reliable perennials (since the garden’s opening in April 2001 — and bloom from as early as April to as late as December!).
We have a very good collection of Lavenders and the cultivar in the center of this picture is the most silvery of them all: ‘Silver Frost.’ Silver Frost Lavender (Lavandula hybrid) outshines all others, contrasting nicely with Ballota (ba-LO-ta) on the Living Wall. Oakleaf Hydrangea in fall attire is the purple foliage above while Furman’s Red Autumn Sage is the red flowers in the background.
For those who love lavenders, Buena Vista Lavender (Lavandula angustifolia) is the only cultivar we have that reliably reblooms. Senior Gardener Mark Gawron just deadheads it once and it completely reblooms like no other cultivar. We are propagating our plants for Powell Gardens Spring Plant Sale the first weekend in May 2010.
This delightfully blue, fall-blooming perennial is the Texas Grass Sage (Salvia reptans). Many of our wonderful Living Wall perennials originally came from High Country Gardens in Santa Fe, NM http://www.highcountrygardens.com/.
The diminutive but delightful fall blooming onion Allium thunbergii ‘Ozawa‘ is in peak bloom with accompanying honey bees. This little perennial grows just above the living wall between golden Angelina Sedum and silvery Valerie Finnis sage — the label in the background is 3″ X 5″ to give you a sense of scale.