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You usually think of leaves being green, but they contain many other plant pigments. Anthocyanins produce the red/purple/blue color found in beets and carotenoids form the yellow/orange colors found in carrots. In the fall as plants are preparing for winter dormancy, they have stored the nutrients they need to see them through until next spring and they shut down their photosynthesis efforts. The green pigment in the leaves, chlorophyll, which harnesses sunlight to produce sugars is no longer needed. As this green chlorophyll breaks down, the other pigments the reds, orange and yellow are allowed to shine. The colors are enhanced by cool nights, so we always get the best fall display when we have sunny days, adequate rainfall and cool nights.

That being said- not all trees and shrubs have beautiful colors hiding beneath the green. Here are some of my favorites.

Yellow is probably the hardest. Of the shrubs, clethra, or summer sweet, has the best yellow foliage color in my opinion. Combined with fragrant white flowers spikes in the summer, it is a good choice for a damp spot. Ginkos, one of the oldest tree species, also put on quite the show. Their fan-shaped leaves turn a brilliant yellow in the fall. These trees are diecious- meaning they have separate male and female plants. Look for male selections as the females produce terribly smelly fruit when pollinated. Some perennials also have attractive fall color- the delicate feathery foliage of Amsonia or Arkansas blue star turns a glowing golden yellow in the fall, and is arguably more attractive than its spring bloom. Witchhazels have lovely yellow fall leaf color as do Norway Maples.

Norway maples were brought to the US by Philadelphia botanist John Bartram in the 1930s. They were planted in abundance because they grow quickly and tolerate urban and other tough growing conditions They were a replacement tree for Elms that were wiped out by Dutch Elm disease. However, they reseed readily making them a nuisance. Norway maples also have a very shallow root system which makes it almost impossible to grow anything under them. I do not recommend them.

Orange- The best shrub for orange fall color is smokebush, or cotinus. Most ornamental cotinus plants have purple foliage through the summer and rather unusual wispy flowers in the spring reminiscent of smoke, but their orange fall foliage is outstanding. Fothergilla, or bottlebrush, is a native shrub 2-4 feet tall with white flowers in early spring before the leaves emerge. It gives a second act in September and October when its leaves become a flaming orange. The trees stewartia and many green-leaved Japanese maples have stunning orange fall color- I love to drive by the house on 222 by the stop light in Quarryville. That Japanese maple must be 50 years old and is just breathtaking in the fall.

Red is probably the most common fall color. Shrubs like oakleaf hydrangeas, burning bush, chokeberry, itea (sweetspire), and most of the viburnums share red-purple fall color. I particularly like the Viburnum nudum ‘Brandywine’ or ‘Winterthur’ bushes because their foliage is glossy; making the color that much more eye-catching. For trees, dogwoods and sugar maples are probably my favorite. On the farm we have a flowering pink flowering dogwood that is underplanted with pink bleeding hearts and white Solomon’s seal. Those go dormant over the summer and the fall garden features blue aconitum and the yellow foliaged amsonia under the red foliage of the dogwood. I almost like the fall show better.

Summer hasn’t quite released us yet, but autumn is coming. As the foliage starts to turn I think about the cycle of nature and how the plants are getting ready for rest. It is beautiful, the heralding of the change of season. And I’m ready for a rest from the gardening season too.

By the time you read this, the big yellow bus will have gathered up my son for seventh grade, my daughter for her last year of elementary school, and all the other school children in the county. Back to School may have us thinking fall, but the garden is not nearly ready to give up the ghost.

There are many wonderful late-summer and fall blooming perennials and shrubs that you can plant now to enhance your landscape with color well after you hang up your bathing suit.

Nothing is more evocative of fall than mums and asters. There are many wonderful hardy mum selections that come back year after year like ‘Cambodian Queen’ a tall clear pink and ‘Autumn Bronze’ a golden flowering mum. In the mum family is green and gold, Ajania pacifica. This plant has green mum foliage edged in silver then bright yellow button flowers in November. Asters range in height and bloom time too. The short ‘Purple Dome’ New England Aster starts blooming in September, while the aromatic aster ‘October Skies’ is true to its name and flowers later. The latest aster in my experience is the Tartarian aster ‘Jindai’ that usually blooms in my yard around Thanksgiving. Mums and asters benefit from a hard trim in June to prevent them from becoming floppy in the fall. Have all pruning done by the 4th of July and flowering won’t be delayed.

But there are many wonderful fall-blooming sunny perennials beyond those. Sedum ‘Autumn Joy’ and its cousins are blooming now around the county and is such a great tough plant for sunny dry spots (though we didn’t have many of those this summer). Willow leaf sunflower (Helianthus salicifolius) loved all the extra moisture and will start blooming in mid-September. ‘First Light’ is 3-4 feet and ‘Table Mountain’ is about half that size. Golden rod, Solidago species come in a range of flower forms from the light yellow upright ‘Little Lemon’ to the deeper gold exuberant flowers of ‘Fireworks’ and ‘Golden Fleece’. All are native to the Eastern US, but have been selected for ornamental characteristics that make them more at home in your yard than in the meadow and field.

For the shade garden, hardy begonias, turtle head, anemones, and toadlily readily come to mind. Hardy begonias are one of my favorite fall plants. They have lovely pink or white flowers, with very prominent red veining on the underside of the leaves. This is so attractive when sunlight hits the leaves. They reseed gently and will fill in those challenging dry shade areas. Turtle head, chelone species, thrive with a little more moisture. Their pink or white flowers resemble snapdragons. They are native to the US and tolerate part sun-shade.

Fall blooming anemones have gotten a lot of press the last few years. ‘Honorine Jobert’, a lovely white selection, was perennial plant of the year in 2016, and more people were exposed to this great fall bloomer. I’ve had the pink ‘Robustissima’ in my yard for the last ten years and it has spread to make a nice patch. It needs thinned a bit in the summer. Where anemones are robust, toadlilies are more a delicate beauty. These intricate white and purple speckled flowers resemble small orchids and are best situated near a path or close to the house where you can appreciate them up close.

There are many great late flowering shrubs to add color to the border or foundation plantings as well. Caryopteris, or bluebeard with its lovely blue flowers, and silvery aromatic foliage is a nice choice. Leptodermis, star flower is blooming in my yard now. It has small tubular purple flowers that have a subtle fragrance. They both reach 2-4 feet tall and wide. They are considered die-back shrubs and bloom on new wood so benefit from a hard trim in the spring. Not to mention all the great fall berrying shrubs and ones with especially attractive fall leaf color. I’m out of room, so look to this space next week for more shrubs to add fall interest to your garden.

Photo above: Tricyrtis formasana

Last week this space featured crape myrtles. Formerly a Southern-only plant, breeding for cold hardiness allowed this summer-blooming shrub to creep further up the coast.

This week, panicle hydrangeas take the spotlight. The most hardy of the hydrangea species, panicle hydrangeas thrive in zones 3-9. Meaning my mother-in-law in Iowa and my classmates in Texas can both enjoy this one. The flower color is not pH dependent like the mopheads, and it blooms on new wood, so you don’t have to be careful with pruning. What’s not to love?

Panicle hydrangeas are native to China and Japan and in the wild grow 8-15 feet. When they were first introduced to US gardeners they were commonly called ‘peegee’ or ‘PG’ hydrangeas which stood for Hydrangea paniculata ‘Grandiflora’. They are still referred to that way in the trade, though the number of cultivars available has exploded. 10 years ago, the most common cultivar was Limelight™. We grew so many of those, it seemed like every neighborhood in Lancaster County must have at least a few. This selection reaches 8-10 feet and the extremely dense flower clusters emerge a lime green and fade to a whitish pink. This one is extremely floriferous. The one at the farm has been gorgeous for several weeks.

Recently, the focus of breeders has been to shrink them down to more comfortably fit in small gardens. ‘Little Lamb’, Little Lime™ and Bobo™ all come in under six feet. A second focus has been to expand the color range and flower form. All of the flowers open green or white then fade to a pinkish tan. Some selections like Pinky Winky™ Firelight™ and Quickfire™ speed rapidly to a bright pink- to almost red. The sepals or modified leaves, are the colorful part of the flower heads. They hold color well, even when dried, for arrangements. Some flower forms look almost lacy with a mix of sepals and the tinier fertile flowers below. Driving around, I am seeing more and more shorter, colorful selections.

These hydrangeas are very forgiving. They tolerate full sun to part shade. I’ve seen them growing in full shade, but wouldn’t recommend it as they won’t flower nearly as well. They also can handle almost any soil condition except standing water. In terms of pruning, you can pick a central leader and encourage them to grow a trunk for the “small flowering tree” look. This was how most of the old ‘PG’ hydrangeas were grown. You can also cut them back hard in the spring to keep more of a multistemmed shrub. They bloom on new wood, so spring pruning is best.

They suffer from very few pests or diseases and are hardy enough to grow in a patio pot over the winter. They are slightly heavy feeders so a bit of compost can help if the leaves are looking a bit yellow.

All in all, they bloom when not much else in the landscape is, are easy to grow with a huge hardiness range, and are not bothered by pests of diseases. No wonder they earned a place in my Top Ten late summer plants.

Photo above: Hydrangea paniculata 'Pinky WInky'

Driving to North Carolina this week two plants were in full bloom and really caught the attention. Crape myrtles and panicle hydrangeas are currently flowering up and down the coast.

The majority of shrubs are spring bloomers with blossoms that last two to three weeks. These two flowering shrubs put on a show for quite a bit longer, up to two to three months. They are also a bright spot of color when much of the garden can look a bit peaked.

Crape Myrtle or Lagerstroemia indica, is a deciduous shrub or small flowering tree native to Southeast Asia.. They were introduced to Charleston, South Carolina by a French botanist in 1790 and since then they have become a naturalized part of the landscape from Virginia south to Florida. They are hardy to Zone 7 but breeding with another species has increased the hardiness well up through Zone 6. More on that later.

They bloom on new wood- meaning the growth put on in the current season. Pruning them hard in the spring will not affect flowering. In this area, often we see tip dieback over the winter so a bit of cleanup pruning in May-June helps the form. The ornamental peeling bark on older plants is quite attractive in the winter- so “limbing them up” or pruning the lower 3-4 feet of growth to expose the trunk on mature specimens is a good idea. In Florida I saw a lot of “crape murder” the practice of pruning them hard to a stub. The new growth was often a bit flimsy. That is not necessary here as they won’t put on 20 feet a year in this climate.

They are one of the absolute last things to leaf out in the spring- often not showing any green until the end of May. On the farm, our fig tree and crape myrtles are the slowpokes. Several years I’ve thought they died and but then they reappeared by Memorial Day. This is not a plant for an impatient gardener.

Most of the breeding has been done at the National Arboretum in the 1960s by famed plantsman Don Egolf. His focus was on disease resistance and improving the hardiness. His hybrids were named after Native American tribes. ‘Pokomoke’ and ‘Tonto’ are his most well-known hybrids. They are still in cultivation almost 60 years later.

Further breeding was done at the University of Oklahoma in the 1980s-1990s by Dr. Whitcomb to improve hardiness. His selections are reliably hardy to Zone 6. ‘Pink Velor’ and ‘Dynamite’ are his most famous contributions. Since then the focus has been on more dwarf selections and Dr. Michael Dirr out of North Carolina and Dr. Michael Uchneat from State college have two hardy, dwarf series respectively- the Dazzles and the Infinitinis which at 2-3 feet are just as at home in the perennial border or foundation planting as they are in the shrub border.

All crape myrtles require full sun. Less than 6 hours of direct sun will adversely affect the flowering. I mean it. We had a walkway down to the deck that dad lined with dwarf crape myrtles, and the ones that were slightly shaded by the house never flowered as well as the ones in 7 hours of direct sun. As an added bonus they generally have a nice orangey-red fall leaf color and the attractive exfoliating bark on the taller specimens.

Well, I’m out of room and didn’t hit panicle hydrangeas yet. That will be next week’s topic. They’ll still be blooming.

Photo: Lagerstroemia 'Infinitini Purple

With the heat wave of early July looming, my wife and I headed north. By the time we got stopped the issue was; do I wear two, three or four shirts and jackets to mitigate the temperature and wind? In fact, if my legs were 30 or 40 feet longer I could have put one foot in Europe and one in North America or at least on the tectonic plates that define the two.

Iceland sits on the Atlantic ridge and was formed by volcanic activity over many years. It remains an unstable area with frequent earthquakes and volcanic eruptions. The terrain is defined by lava fields, level coastal plains and sharp cliffs leading to an interior of modest mountains and glaciers. Less than two percent of the land is usable for agriculture.

The agriculture that does exist is grass based; supporting lots of sheep, a few cattle and their loved horses. Defined as a national treasure, the horses have descended from those brought by the early Norse settlers about a thousand years ago. Iceland forbids the importation of horses, and any horse that is taken out of the country will never be allowed to return. None leave.

One interesting visit was to a geothermal energy plant. It was built over an inactive volcano and supplies electricity and hot water to Reykjavik, the capital city. It consists of stem generators, heat exchangers and three pipes drilled into the ground. The pipes are just over a mile long, just under a mile and the equivalent of a deep well.

Water coming from the deep well emerges as steam and near boiling water. The steam runs the electric generators while the hot water, that is too mineralized to use, goes to the heat exchanger to heat water from the shallow well. The newly heated water heads for consumers while the original water is returned to the ground by way of the middle length pipe.

Home heating and electricity costs about 50 dollars a month for the typical home. We were told that energy was cheap but everything else was expensive. When two-fast food type cheeseburgers or a single bag of laundry washed and folded at a hotel stop came in at 40 dollars, we agreed.

The availability of so much hot water permits the city of Reykjavik to have pipes under many of their streets to melt winter snows.

Iceland is the size of Kentucky with a population that is just over half of that of Lancaster County. Everybody lives along the coast with two-thirds living in the capital city of Reykjavik.

Purple lupine was the main wildflower seen growing along the roads. There were huge swaths. I guess that explains why we struggle to find cool enough conditions to make that one happy. The pansies were also dominant and beautiful in containers and gardens.

There were more trees than expected. None were natural regeneration. All had been planted. An examination suggested that evergreens might add six inches a year and faster growing deciduous might grow a foot a year. History suggest that Iceland was forested prior to the last ice age. The Norse settlers starting in 930 AD also cut wood and lumber for their needs, contributing to the demise of the forests.

I saved it for last. Yes, there were birds. Some actually live that far north, and many birds that spend most of their life at sea nest in the cliffs of northern areas like Iceland. Shortly after my return home, I made a brief visit to the Octoraro Reservoir and saw 22 species. When compared to the nearly 40 species I saw in Iceland the only match was starlings. They were introduced and not native in either place. You get the picture.

Iceland, “the land of fire and ice” was a nice trip but also another reason to be thankful that my ancestors chose Lancaster County as home.