Tuesday, January 29, 2008

Elegant Silvers in Winter Perennials

This photo from the Island Garden depicts three of the finest perennials with elegant silver foliage in the winter landscape. They are growing in the living wall: Santolina Santolina chamaecyparissus (foreground), Silver Frost Lavender Lavandula 'Silver Frost' (middle plant) and Dwarf Horehound Ballota pseudocictamnus 'Nana' behind. Each has a different subtle shade and unique texture so they create quite a pleasant composition when grown together. All need full sun and good drainage! Our most successful santolinas originated from a special zone 5 hardy strain from High Country Gardens http://www.highcountrygardens.com/ in Santa Fe, NM. The Silver Frost Lavender is another specialty plant from High Country Gardens. Dwarf Horehound is more readily available.

Here is a closeup of a young Silver Frost Lavender in the living wall. No other lavender is so silvery!

The rare Partridge Feather or Silver Feather Tansy Tanacetum densum ssp. amanum has some of the most beautifully textured foliage of any plant at Powell Gardens. We trialed it from Siskiyou Rare Plant Nursery http://www.siskiyourareplantnursery.com/ in Talent, Ore. It has been successful in a place of good air circulation in the living wall for years!

The evergreen, needle-like tuft of foliage of Firewitch Dianthus Dianthus gratianopolitanus 'Feuerhexe' make it an outstanding plant when not in bloom. In late spring it is covered with vivid fuchsia flowers. It was Perennial Plant of the Year in 2006 and is now a Plant of Merit for our region.

The silvered, purple leaves of Regina Coralbells Heuchera 'Regina' are some of the best for hardiness and durability! This coralbell has staying power and its "evergreen" leaves are beautifully contrasted when grown among Angelina Sedum Sedum rupestre 'Angelina' as can be seen growing on the Island Garden.

Read the book Elegant Silvers by Jo Ann Gardner and Karen Bussolini (Timber Press 2005) for more ideas with silver plants.

All photos were taken by Alan Branhagen in January 2008 at Powell Gardens.

Friday, January 25, 2008

Chapel Ice Sculpture

Janet Heter, Senior Gardener in the Rock & Waterfall-Meadow-Chapel Gardens shows off the Chapel Fountain this winter. It has become a beautiful ice sculpture with our recent subfreezing weather adding to the peacefulness and serenity of the chapel.

Renowned architect Faye Jones designed this fountain as part of the entrance space to our chapel, which he also designed. Ice fountains like this have become popular in places like Boston or Minneapolis. Recent prolonged subfreezing weather have made this beautiful prairie style fountain a wonderful sight of our winter season.

The recent cold snaps have actually not been that bad. It has not gotten colder than zero F out here in our cold valley at our official weather station. Many sheltered areas of the gardens are usually 5 degrees or more warmer than our weather station's site. We still design our gardens with plants that can easily handle -15F though such cold temperatures have not occured in more than a decade. Zone 7 (0-10F) is still a mild winter for us.

photos by Alan Branhagen taken at Powell Gardens on January 25, 2008

Victoria Waterlilies Germinate and Grow!

Germination station for our Victoria waterlilies is a standard 10 gallon aquarium. Here Mark Gawron, Senior Gardener -- Island Garden observes conditions for the germinating seed: the temperature is maintained at a steady 89F. Note the bit of water lettuce floating in the corner of the aquarium to keep algae growth down.

Mark inspects the Victoria seed on a daily basis for germination. He exchanges the water in the baggies with fresh water from the aquarium every other day.

A germinating seed looks like this -- the long, thin leaf is a filiform leaf. This seed is almost ready to be planted.

The seed will be planted in a small cup in the larger aquarium. See our new light above which helps this whole process because our natural light conditions at this time of year are not enough for these Amazonian plants. A timer turns this light on for a couple extra hours of light each evening.

Mark mixes peat moss and a couple lumps of natural clay and puts it in the bottom of a cup. He places clean sand (washed to remove excess salts) over the peat & clay. The cup is placed in the "nursery" aquarium to warm up before the germinated seed is put in place.

The germinated seed is quickly transferred to its new home, allowed to drop into its new cup to grow.

A staple is used to secure the germinated seed to soil for continued growth. (This shot is looking into the aquarium.)

This Victoria was one of our first planted. It germinated 12 days after nicking. It has a nice filiform (long narrow) leaf and its first hastate leaf (the arrow shaped one). This plant has some nice roots you can't see as well. Soon the floating leaves should be emerging. When the floating leaf emerges it is time to transplant them again.

Stay tuned to watch the continued growth of these magnificent plants...

Photos by Alan Branhagen taken at Powell Gardens

Tuesday, January 22, 2008

From Tiny Seeds our Flowers Grow!

Faith in a Seed! Many of Powell Gardens' flowers arrive as tiny seeds. In fact, this tiny petunia seed has been "peletized" (coated to make it larger and workable). The actual petunia seed is almost like dust.

The tiny peletized seeds arrive in small vials, usually in quantities of 1,000.

Jennifer Comer, Senior Gardener - Grower, shows off this handy contraption called an E-Z seeder. It's a pan-like tray with a grid of tiny holes in it that correspond with the cells in our seed growing trays. The tiny seeds are placed in this pan-like tray and the vacuum turned on! The seed are sucked into the grid of holes that correspond with their seed tray. The vacuum is not turned off until you flip this upside down over the appropriate seed tray, then the suction is released and the seeds fall into their new home to germinate. Can you imagine placing a tiny seed by hand in each tiny cell?

Each seed tray (288 plug tray depicted) is labeled with the name of the plant, the week it is to be planted (Wk(week) 4: January 21-25), the number of days it will need to be a "finished" blooming plant (75-78 days), L= the seed needs light to germinate (don't put soil over the seed!), 6-10d= 6-10 days to germinate; sale means it is grown for our Spring Plant Sale, Extra means it will be available for gardeners to plant, and Friends means it will be available as a free plant for new and renewed Friends of Powell Gardens memberships. Horticulturist-Grower Donna Covell figures this all out!

Here is what seed sown on Week 1 (Dec. 31-Jan 4) looks like. These tiny dusty millers do not yet have their characteristic silvery look.

Jennifer Comer inspects trays of seedlings in the greenhouse. It takes our entire greenhouse team of Horticulturist Donna Covell, Jennifer and gardeners Penny Hudson and Eric Perette to make sure these are watered properly and to keep any pests or diseases at bay.

The next step from the seed tray may be these six packs called "six-o-sixes" because there are six six-packs in a tray. Here, newly transplanted calendulas will grow to blooming size. Once in bloom or "finished" they will be planted outdoors. Calendulas are very hardy and will be planted outside in the later part of March. Many people buy bedding plants in six packs but we put more than one plant in each cell for a fuller display.

These ornamental cabbages and kales are already moved up to 6-inch pots so they will be spectacularly showy plants when they are planted outdoors for you to see in late March.

Stay tuned to see continued progress of our flowers in our greenhouses. Remember all the flowers of all the tomorrows are in the seeds of today!

All photos were taken by Alan Branhagen on January 22, 2008, in the Powell Gardens greenhouses.

Friday, January 18, 2008

Sharp Gardening

Yuccas and Cacti are two spiny succulent groups of plants that act as evergreen shrubs in the winter landscape. Their striking form and texture provide great variety to the shrub or perennial border. Their colors hold true despite severe cold so they are always a welcome sight on a winter's day.

Golden Sword Yucca (Yucca filamentosa) is a yellow variegated selection of a yucca native southeast of Missouri & Kansas. It is still very hardy and tolerant of our humidity and regular garden soil so is a colorful standby for winter gardens in Greater Kansas City. A glowing sunset back lighting the foliage can be stunning!
Bright Edge Yucca is another yellow variegated cultivar of yucca but with the yellow bands down the leaf edges. This cultivar is a bit more refined and almost appears to be aglow with an inner warmth.

Hairy Yucca (Yucca filamentosa 'Hairy') is a difficult to find cultivar (see fairweathergardens.com) but is unique with its inordinate amout of the leaf-edge filaments that give this species its name. A delightful detail in strong contrast to its stiffly spikey leaves.
Next June our yuccas will be crowned by sturdy 4-6 foot candelabras of white, bell-like flowers. If Mrs. yucca moth is around she will individually pollinate flowers and lay an egg. The young caterpillar will eat the developing seeds but never damages them all. Yuccas cannot be pollinated by anything else but a skilled gardener! If pollinated, the flower stalk will become woody and adorned with beautiful upfacing pods -- adding additional interest to the following winter's landscape. Our yuccas depicted can all be seen in the Fountain Garden so are just 2 seasons old. We expect them to have their first blooms this summer.
Bigroot Prickly-Pear (Opuntia macrorhiza) is a native cactus you can see growing wild along our Byron Shutz Nature Trail's highest points. We have taken some "pads" of these wild plants and transplanted them to the Island Garden where they spill over the top of the wall (see depiction). Their evergreen pads are heavily adorned with double spines - one of which is always much larger than its twin. This cactus is on the Missouri Endangered Species List. Note the purplish-red fruits which are great winter wildlife food.
Eastern Prickly-Pear (Opuntia humifusa) is another Missouri native cactus but is much more widespread and found throughout Eastern North America. Its pads are less spiney and singly spined.
Both our native prickly-pears become beautifully weathered as they dehydrate themselves to survive the winter. They are beautifully displayed on the Island Garden where they spill over the living wall -- forced to be confined between shady shrubs above and the wall below. Come back to see them around the summer solstice when they will be in full bloom with gorgeous, large yellow blossoms. The flowers are very pollen and nectar rich and attract a plethora of beneficial pollinators. We highly recommend them as garden plants but BEWARE where you put them! The spines are sharp and smaller, hair-like spines can be a real nuisance where only rubber cement can remove them from your skin.
All photos taken by Alan Branhagen at Powell Gardens on January 9, 2008.

Wednesday, January 16, 2008

The Perennial Garden's Winter Bones

Our Perennial Garden displays some of the best garden design at Powell Gardens. At the age of 17 many of its plants are beyond youthful size. These backdrops, or "walls," of the perennial beds make the garden a delightful, human-scale experience. Take a virtual tour with Senior Gardener Jay Priddy and share some of his favorite winter plants. We hope this entices you to come out and pick your own favorites soon!

Winter tests the character of gardeners and reveals the character of so many garden plants overlooked in the exuberant green chaos of summer. For us it is a time of planning, preparing, dreaming, and waiting. For the hardy survivors and hardened skeletons of last year's growth it is a time of dreaming and waiting as well - dreaming of rebirth and waiting for spring. Even in the absolute "dead of winter" a garden can be a fascinating and rewarding place to spend a day. This is on average the coldest week of the year, but a visit now can reveal the bare bones on which every garden is built. We will follow the "planting pyramid" from perennial grasses to shade trees on this tour. Please join me and enjoy the views!

The low angle and silvery light of the winter sun provides wonderful backlighting for ornamental grasses while illuminating their seedheads to incandescence. Morning Light Miscanthus (Miscanthus sinensis 'Morning Light') literally glows in the late-afternoon light. One of my new "favorites" is Wind Dancer Lovegrass (Eragrostis elliotii 'Wind Dancer') with its delicate seedheads held aloft on wiry stems that have survived the worst winter has thrown at it. Yet the big and bold stalks of the Ravennae Grass (Saccharum ravennae) steal the show for me. These 10-12 foot stalks have weathered the snow, ice, wind, and rain to remain picture-perfect in January. This one is protected by a heavy load of mulch for protection.

Another of the senses pleasantly stimulated at this time is hearing. Our seemingly permanent Missouri breeze creates a broad range of sounds in the depth of winter. The high-pitched tenor of the finer grasses like Miscanthus are countered by the deeper baritone of the reed-like grasses whispering in the wind. The rattle of leaves, the occasional warbling and twitter of birds, and the gentle "shushing" of pine surf add their pleasing notes to an otherwise peaceful setting ripe for relaxing contemplation.

Harry Lauder's Walkingstick

Seven Sons Flower

China Snow Peking Lilac

Some plants really show their finer qualities when undressed. The structure and architecture of many woody plants and the color and quality of their stems and bark can be appreciated best when they shed their cover of leaves and shine for us in winter. Harry Lauder's Walkingstick Contorted Hazel (Corylus avellana 'Contorta') is a prime example. A plant that draws puzzled looks when leafed-out in summer becomes a stunning specimen of spaghetti-like, twisted branches that awes me every time I see it in winter. Less is more indeed! Did you know this plant was named for a famous vaudevillian who carried a crooked walking stick as a prop on stage? Many examples of beautifully colored exfoliating bark are also accentuated in the winter. Our Seven Sons Flower (Heptacodium miconioides) displays shaggy flags of brown and white bark flapping in the breeze with exposed, smooth, bone-white trunk and branches glowing in the winter light. This is difficult to appreciate once the leaves arrive and the surrounding plants rise up. Another subtle stunner one might miss in other seasons is the bark of the China Snow Pekin Lilac (Syringa pekinensis 'China Snow'). The picture above and on the right shows the gorgeous cinnamon-brown, tissue-like exfoliating bark and the contrasting white horizontal dashes of the lenticels quite well. Notice how the light reflects off the smooth trunk. This alone is worth the chilly walk through the gardens!

Some evergreen shrubs and trees become chameleons as the temperatures dip down and winter challenges their defiance. The Evergreen Tapestry Hedge in the Perennial Garden has such a plant. Berckman's Golden Oriental Arborvitae (Thuja orientalis 'Aurea Nana') draws attention in all seasons with a remarkable lime-green coloration in spring and summer and a russet blush developing on the branch tips as winter deepens. Oriental arborvitaes always remind me of exotic corals growing on dry land and this one is no exception. Alan designed this hedge with a unique combination of three evergreens in triplets that do not repeat throughout the entire sinuous line of shrubs. The contrasting rich green of Emerald Sentinel Eastern Redcedar (Juniperus virgiana 'Emerald Sentinel') and the blue-green of Blue Eastern Redcedar (Juniperus virginiana 'Glauca') is lovely in every season.

Small trees can also lend interest to the winter landscape when their bare branches are exposed against the bright blue winter sky. A constant favorite among staff and visitors is the Scarlet Curls Hankow Willow (Salix 'Scarcuzam') dominating a curve on the walkway in the heart of the Perennial Garden. This gal is an unrepentant show-off all year. Long, twisting tendrils of silky willow leaves draw "oohs" and "ahhs" in spring and summer, but it is when she disrobes that the fantastic structure of this tree is revealed. Look up when you walk beneath her and you will be rewarded with a mass of coiling branches tapering to hair-like twigs outlined against the sky. Be sure to note the other small trees like redbuds and dogwoods before they "dress" for spring.

High on my list for winter interest are our groves of Common Persimmon trees (Diospyros virginiana). As they mature the rough, crackled pattern on the rugged bark becomes deeper and more interesting (even to lichens as the picture above demonstrates). Very few woodies can match this one in the wow-what-a-bark! category. I also admire the form and shape of the groves. These trees are interconnected (like aspens) and this relationship is made evident in their growth pattern.

Evergreen trees are another backbone of a well-balanced garden design and a welcome statement of color in any winter setting. The Japanese White Pines (Pinus parviflora) we have in the Perennial Garden are a wonderfully exotic addition in my view. Their horizontal, uneven branching and spiky tufts of blue-green needles provide a more formal, oriental twist that is admired by many visitors. With so many options in small evergreen trees this is a good area to experiment with color, shape and form. We have many examples throughout Powell Gardens for you to observe and choose the best choice for your own garden. By the way, winter is an excellent time to do just that!

Our final stop on this tour belongs to the "big boys" of the garden - the large shade trees. Once these guys leaf out and become giant green canopies in our woodland beds it is much more difficult to observe and admire their basic structure. On the picture above at left we have what Alan observed as a "dance" of Swamp White Oaks (Quercus bicolor) outlined by the powder-blue sky. I can almost imagine one tapping the other on the trunk with the query, "Would you like to dance?". What do you see? Do not forget to look up as you walk through the garden. Each tree - whether hickory, oak, tuliptree, or korean evodia - has its own personality as expressed through form, size, shape, or color. Some convey strength, power, and age. Others reflect elegance, grace, and youth. Look up and maybe you will see the halfmoon looking down with a little jealous peek into this wonderful winter landscape at Powell Gardens.

All photos taken by Alan Branhagen on January 15, 2008
Virtual Tour text by Jay Priddy, Senior Gardener -- Perennial Garden

Friday, January 11, 2008

The Magnificent Victoria Waterlilies Have Arrived!

I am often asked what the horticulture staff of Powell Gardens does in the winter. The process we follow to grow the magnificent Victoria waterlilies shown above (photo taken last summer by Mark Gawron, Senior Gardener for the Island Garden) starts now, in midwinter. The Victoria waterlilies have arrived!

Mark Gawron says Victoria waterlilies are the prize jewel for avid water gardeners. I like to start the Victorias in mid-January. We receive the seeds from Florida and I credit the process of cultivating the Victorias from Water Gardens International's website http://www.watergardensinternational.org/."

We received five varieties of Victorias this year. The seeds arrive from Florida in labeled plastic baggies filled with water. Victoria amazonica depicted here.

Mark Gawron nicks (scarifies) the seed as soon as possible, keeping the seed out of water for the smallest amount of time possible. This is a slow process; each seed must be scarified individually by hand.

Nicking involves using a scalpel to pop the operculum off without touching the embryo underneath. After nicking, Mark immediately returns the seed to the plastic baggie filled with water and floats the baggies in an aquarium maintaining a temperature of at least 85F. This is the Victoria's seeds stratification proces. Germination should take place in 3 to 12 days.

Stay tuned for the continued process... and watch our Victorias grow. In July, Mark will play pollinator of the Victorias in the Island Garden pools by the moonlight!

All photos taken by Alan Branhagen on January 11, 2008.

Thursday, January 10, 2008

Sedums for Winter Ground Color & Cover

Some or our most colorful groundcovers have really shined this winter at Powell Gardens. They are all sedums: tough succulent perennials from various parts of the world. The picture depicts sweeps of three varieties in the Dwarf Conifer Garden: Angelina Sedum (Sedum rupestre) on top, Weihenstephaner Gold Sedum (Sedum floriferum) in the middle (it is named after its golden yellow flowers!), and Blue Spruce Sedum (S. reflexum) on the bottom. I think these three varieties represent the best of the easy landscape sedums for our climate and the best in winter gold, winter red and winter blue foliage color. They all require full sun (or only part shade) and good drainage.

Angelina Sedum is a wonderful blend of oranges and rose pinks beyond its overall gold color. This picture shows it paired with silvery-leaved lavender (snuggled in cut redcedar bows for winter protection) and Vintage Gold Chamaecyparis in the upper right corner. This tapestry of winter plants can be seen in the Fountain Garden.

Angelina Sedum shown in closeup detail. This sedum turns brilliant chartreuse yellow-green in spring and remains that color until cold weather returns in autumn. It is at its most beautiful in winter!

Blue Spruce Sedum is overall dusty silvery-blue but can have lovely tints of rose or lavender in winter.

Voodoo Sedum (Sedum spurium) is one of the best for red foliage color but does not make as nice of solid mat as 'Weihenstephaner Gold' in the first image. It is great for the edge of a bed or spilling over a wall as shown here on the edge of the dwarf conifer garden. Sprigs of Blue Spruce and Angelina sedum set it off nicely.

Jelly Beans Sedum (Sedum album) makes a wonderful true green sedum for edging and rock walls. Here it grows between Angelina Sedum and the rock wall on the Island Garden. Its winter, green succulent leaves are very tiny in winter.

Blue Carpet Sedum (Sedum dasyphyllum) makes a soft blue-green carpet for areas that have afternoon shade. Here it can be seen as a groundcover in beds just before you cross the bridge onto the Island Garden. Don't forget the sedums when designing and adding to your garden for 2008. They provide marvelous color and texture in the often dreary winter landscape. They all are wonderfully drought tolerant too. All of the sedums shown here will be at Powell Gardens' Spring Plant Sale the first weekend in May.

All photos taken by Alan Branhagen on January 9, 2008, at Powell Gardens