Spring Has Sprung!

Spring has really sprung at Powell Gardens and the gardens are giddy with flowering flora. The sights and scents of the flowers are especially captivating after a winter without them in the landscape.

We had a freeze Wednesday morning (29F) and I thought our magnolias would be toast but they were just tight enough in bud to endure and burst forth now with glorious flowers. This is the Galaxy Magnolia (Magnolia liliiflora 'Nigra' x M. sprengeri 'Diva'). The scents of this and some other magnolias are somewhat musky but remind me of my experience-rich childhood and the neighborhood saucer magnolia.

The path by the Trigg Building is now a tunnel of softly sweet-scented Star Magnolias (Magnolia stellata). The star magnolia flowers are a bit disheveled on close inspection but overall wonderful -- they endured hot winds (Sunday), cold winds (Monday), hail and torrential rain!

Magnolia 'Butterflies' (Magnolia acuminata x M. denudata 'Sawada's Cream') is one of the best yellow-flowering magnolias with small waterlily-esque, delightful and musky scented flowers. This magnolia always draws attention at the Visitor Center trolley stop and should be in full bloom this weekend.

The burgundy goblets of Magnolia 'March till Frost' is a complex hybrid ((Magnolia liliiflora x cylindrica) x Magnolia 'Ruby') that does repeat flower a bit all season. It did survive the vagaries of this spring and is gaining rank on my list of Magnolia favorites.

This unassuming shrub in the Heartland Harvest Garden grabbed my attention as I walked by with its phenomenal and alluring aroma. The small yellow flowers of Clove Currant (Ribes odoratum) are a sweet and rich with a clove-like scent. I also remember this shrub from childhood when it bloomed in older neighborhoods of my hometown as I walked home from school. It lost favor from gardeners for many years but now is back in popularity as it produces edible black currants great for preserves and pies (and fresh eating too)!

The plum trees are also in bloom in the Heartland Harvest Garden and just starting to open in the natural areas of the grounds. The HHG has a superb collection of plums ( Plum 'Burbank Red Ace' shown) and their flowers are wonderfully fragrant. I must admit the plum blossom scents took me back to my childhood visiting my Grandpa and Grandma on the farm in Iowa. They grew on the fencerows perfuming the air in spring and Grandma always made a memorable preserve out of the plums and mixed it with apple.

Two plums in particular stand out in our collection: The Shiro Plum shown here grows on the south side of the Learning Shed and has a beautiful spreading crown. Its plums are yellow when ripe and a favorite of Horticulturist Matt Bunch.

Our other favorite is the Toka Plum shown here just south of the corn crib. It is sometimes called the bubblegum plum because its sweet plums have a remarkable bubblegum-like flavor which Matt described and then read that was another name for this plum! This is the plum whose ripening plums are depicted on our set of note cards available to Friends members. If you have room for just two plums, plant Toka and Shiro and they do pollinate each other. We do have many more varieties, each with their own merit and I captured their images for documentation and future reference (but I don't want to put you to sleep looking at them all here).

The Perennial Garden's beds are filled with Daffodils and spring has burst forth throughout Powell Gardens. The weekend sounds like it will be warm and mild and that predicted rains will happen at night! Come explore the fabulous flora now in bloom and may its sights and scents bring back fond memories or create new ones to reflect upon. Springtime is my favorite season with renewal of life in a burst of beautiful optimism for all to enjoy.

Lights, Camera, Azaleas!

The Lights Azalea Hybrids are currently in full bloom at Powell Gardens. The Lights azaleas were hybridized by the University of Minnesota and most involve Missouri's only native azalea the Roseshell Azalea (Rhododendron prinophyllum). Unfortunately our native azalea defies captivity, in other words, it won't grow away from where it is native no matter how hard we try to cultivate it! I am glad the wonderful fragrance of American native azaleas is still present in most of these hybrids so be sure and take time to smell them. Look for all our Lights Azaleas in the Rock & Waterfall Garden, most along the walk along the north side of the garden (that takes you to the trolley stop).

Candy Lights Azalea is one of the newest and best of the Lights Azalea hybrids with fragrant pink flowers, clean foliage and a compact form.

Rosy Lights Azalea may have the best fragrance of the group and looks most like our native azalea. The flowers are much more rosy pink than the shell pink of wild azaleas. This shrub blooms without any leaves so looks like a full pink bush right now.

Tri-Lights Azalea has white, pink and yellow flowers and is one of the newer hybrids. It is a great performer and can be seen in the core of the Rock and Waterfall Garden between the two bridges.

White Lights Azalea opens softest pink from pink buds and ages to pure white. It is intensely fragrant and perfect for an evening or white garden.

Northern Hi-Lights Azalea has creamy young flowers with an egg yolk blotch on the upper flare -- as the flowers age they are clearly white with a yellow hi-light. The flowers just opened in this picture so are still in the creamy stage. I also really like this plant for an evening or white garden. It is also wonderfully fragrant.

Lemon Lights Azalea is a rich lemony yellow and fragrant too.

Golden Lights Azalea will stop you in your tracks as you walk by: it will first capture your attention with its wonderful aroma and then with its large, golden-orange flowers.

Spicy Lights Azalea is more of a bronzy, pinkish-orange and the first of this hybrid group to bloom. I was happy to see it is still blooming (you can see a floret dropping at the bottom of the image).

Mandarin Lights Azalea is the most vivacious of the group in glowing bright orange. It is a favorite nectar source for hummingbirds and several of our large swallowtail butterflies. I actually expect the first Giant Swallowtails to emerge when this flower blooms and can count on seeing our largest butterfly nectaring on this shrub. This cultivar is not fragrant.

Northern Lights Azaleas are available at many local garden centers. They are a bit tricky to get established in local gardens because of our heavy soils. Here are some tips to be successful with this group of deciduous azaleas at home:

1) Select a site that does not have hot afternoon sun, morning sun is best or light high shade. Lights azaleas grow and bloom nicely in the Rock & Waterfall Garden in full shade of deep rooted oaks and hickories but flower more heavily in more light. Do not expect them to survive in dense shade of maples and lindens which also have voracious surface roots.

2) Make sure your planting site is elevated for drainage and amend the soil with peat or other organic matter like Beats Peat blocks (available at local Westlake Hardwares). I mix in the organic matter with the topsoil in an extensive area.

3) Lights azaleas are often grown in containers in a very light, peaty soil. Be sure and break up the root ball before planting them. I like to split the root ball in 3 places around the sides and literally rip each section up from the bottom. It sound cruel but azalea roots are shallow in the garden and this forces new roots into your topsoil. Most failures occur when folks just plant the soil ball as is and the shrub does not root into the surrounding soil!

4) Mulch your azaleas with pine bark, pine needle or oak mulches if possible. Use your own oak leaves or pine needles whenever possible. Azaleas are shallow rooted and this helps keep them cooler and moist.

5) Water azaleas only when they dry out until they are established and during stressful dry spells. Fertilize with an acidifying fertilizer specially made for Rhododendrons, Azaleas or Camellias.

Two cultivars of Red Horsechestnut (Aesculus x carnea) trees are in full bloom near the Rock & Waterfall Trolley Stop. Red Horsechestnut is a hybrid between Missouri's native Red Buckeye (A. pavia) and the European Horsechestnut (A. hippocastanum).

This is the 'Fort McNair' Red Horsechestnut with carmine pink flowers.

The cultivar 'Briotii' has the most vivacious pinkish red flowers of any of the cultivars. Red Horsechestnuts are very popular in the gardens of Europe but do very well here too. Fort McNair is actually selected from Nebraska. Give them a try for a late spring blooming, moderate sized tree -- they are available at many local garden centers. They also make colorful companions to the Lights azaleas.

The Season of the Greenhouse

'Tis the season of the greenhouse! More than 1,000 varieties of plants have been ordered and sorted for sowing and growing in the Powell Gardens greenhouses. For the next 3 months the greenhouses will be rockin'! The new Heartland Harvest Garden has added more than 350 seasonal edibles and vegetables to the process.

The greenhouses look empty to begin the season, but as the seedlings get transplanted and spaced they will soon be bursting at the seams. Already trays of seedlings remind me of Midwestern fields.

Flowers produced for color and fragrance in the conservatory display are really starting to sing. This is a true red Ranunculus sometimes called Persian Buttercup. Ranunculus are one of our favorite cool season flowers for use in containers; just 5 short weeks until we begin putting cool season flowers outdoors.

This beautiful and extremely fragrant Primrose (Primula acaulis) is the new cultivar 'Pageant Salmon.'

Osteospermums (African Daisies) are another favorite cool season flower; this is the cultivar 'Lemon Symphony.'

The Primroses actually come in almost all colors from red to yellow and almost blue in this mix. The warmer colored flowers seem to be more fragrant.

Ranunculus also come in a kaleidoscope of colors including this nearly true violet seedling.

This little green "nubbin" in the greenhouse is a new fruit of a MANGO! We are carefully watching how our new dwarf, grafted mangoes fare and whether fruit will be produced and ripen through our hot summers in containers outdoors.

Our coffee plants our doing well, too. We formerly had some large specimens that outgrew our greenhouses. We were successful in flowering and fruiting our old plants. Coffee flowers are white and intensely fragrant, the ripe fruit are red and of course it is the seed "bean" inside the fruit that is dried and ground to make coffee. These plants will go on permanent display in the Heartland Harvest Garden's greenhouse.

The new growth on the purple podded variety of cacao (Theobroma cacao) has beautiful pink new leaves. If you don't know cacao, it is the plant that flowers on its trunk to produce acorn squash-shaped pods that contain the seeds from which CHOCOLATE is made. We have three varieties of cacao and all are doing better than I expected. It is a fussy plant demanding heat and high humidity.

We can't wait to share 2009's crop of plants with Powell Gardens' visitors. As long as Mother Nature cooperates, we'll start planting the outdoor beds at the Visitor Education Center on March 16. Yes, there is a whole host of plants that like it cool and can tolerate frosts. The Heartland Harvest Garden won't open to the public until June 14, when all our interesting tropical food plants will go on public display.

The Year of the Lily at Powell Gardens

The ample moisture and more reasonable temperatures have made the summer of 2008 the year of the lily at Powell Gardens. Lilies (Lilium spp.) are bulbs, most with exceptionally showy flowers and some with intense fragrance.

There are hundreds of species of lilies and the Easter Lily (Lilium longiflorum) is one of the most popular. Easter lilies are actually from Asia but forced into bloom for Easter sales. Hardy selections of Easter Lily bloom in midsummer and are pristine white with a very fine aroma. These were photographed in the Perennial Garden. The Madonna Lily (Lilium candidum) is the actual lily that is the symbol of purity and faith for Christians. Madonna lilies must be ordered now and planted by Labor Day because they must grow some foliage before fall.


There are thousands of cultivars of lilies but luckily they are assigned into several groups: Asiatic Lilies are some of the easiest to grow in our climate and come in a wide array of colors from white to yellow, orange, red and burgundy: this is the cultivar 'Savannah' in the Perennial Garden. Most Asiatic lilies are scentless and the flowers face upwards.


Tumpet lilies like this cultivar 'Golden Splendor' on the Island Garden are tall with trumpet shaped blooms that are also fragrant. This clump was hit hard by the Easter freeze of 2007. It languished all last year but we "let it be." This year it came back as if nothing had happened and seemed to make up for lost time!


Oriental Lilies are some of our most fragrant and require proper siting in our climate. These Stargazer Oriental Lilies were photographed in the Perennial Garden--in the afternoon shade of native trees. Oriental Lilies can literally bake in our hot afternoon sun so that the flower buds brown and never open.

New hybrid lilies have created quite a splash. This is a LA Lily: LA stands for longiflorum (Easter) - Asiatic (not Los Angeles!). LA lilies have the colors of Asiatic lilies, the fragrance of Easter lilies, and an exceptional hybrid vigor. This is the cultivar 'Gerrit Zalm' in the Perennial Garden which would be a great addition to a moon or white garden.

Some of the newest hybrid lilies show incredible vigor! This is a new Orienpet lily. Orienpet stands for Oriental - Trumpet hybrid lilies. These have the most hybrid vigor, good heat resistance and awesome fragrance. The unnamed hybrid shown from the Perennial Garden is well over 6 feet tall. Unfortunately the colors of many Orienpet lilies are just plain ugly blends of pink and yellow.

Powell Gardens' favorite Orienpet lily is the cultivar 'Silk Road,' which graces the entrance to the Island Garden's Sunken Garden. It has good color, fragrance and abundant bloom on sturdy 6 foot stems! Make sure to include lilies into your gardens for next year--there are many species and even more cultivars to choose from. Many of the later blooming varieties are still in bloom for ideas at Powell Gardens.

Exquisite White Flowers Exclusively at Powell Gardens

Some of our most exquisite flowers are currently in bloom and many of them are in elegant pure whites and from plants rarely seen in this region. White flowers are a favorite to use near outdoor seating and entertainment areas as they literally glow at dusk. Most are also very fragrant too -- a very important aspect to consider in good garden design. Here are some to search for at Powell Gardens and for use in your own garden.


The magnificent Ashe Magnolia (Magnolia ashei) flowers are almost 8 inches long in bud and open out on their second day. This small tree is found wild only in the Florida Panhandle but is hardy as far north as Chicago! Look for Powell Gardens' tree below the south bridge in the Rock & Waterfall Garden where the wonderfully scented flowers can be easily viewed. Its huge tropicalesque leaves have a silvery underside and are simply stunning in a breeze, but this tree always needs a sheltered, wooded site so it will not get too wind whipped! It's one of the finest trees for a secluded patio space and available by mail order from places like Pine Ridge Gardens or Fairweather Gardens.

The wonderfully true white flowers of the Charles Coates Magnolia (Umbrella Magnolia M. tripetala x Oyama Magnolia M. sieboldii) is another rarity in bloom in the Rock & Waterfall Garden with luscious tropical looking leaves adorning each flower. This tree is also hard to find -- we got ours from Fairweather Gardens about a decade ago.

The graceful downward facing Oyama Magnolia (Magnolia sieboldii) is the epitome of style. It is native to Eastern Asia and the Japanese place the cut flowers in high vases so you can look up into the fragrant flowers. The Oyama Magnolia demands shade in our climate and remains a large shrub. Look for plants in the Rock & Waterfall Garden. I would love a garden where it grew above a retaining wall alongside an outdoor seating area where it would canopy over to create a wonderful space.

The Chinese Allspice (Sinocalycanthus chinensis) has waxy downward facing flowers. This is a heat tolerant large shrub. Our oldest plant bowers over the path to the lower deck in the Rock & Waterfall Garden. It is beautiful but emits no scent. Seedlings from this large shrub are already quite large along the upper walk in the Rock & Waterfall Garden. This rare Chinese plant has been hybridized with the American native Carolina Allspice "Sweetshrub" (Calycanthus floridus) to produce the new cultivar 'Venus' with the beautiful white flowers of the Chinese plant and the awesome fragrance of the American sweetshrub. Its new botanical name is a mouth full: X Calycalycanthus raulstonii. The X before the Genus name means it is a hybrid between two Genera.

The China Snow Peking Tree Lilac (Syringa pekinensis 'China Snow') is in full bloom at the entrance to the Perennial Garden in the fragrance beds. This tree has fragrant white flowers but nearly so nice as an old fashioned lilac (more privety if you know what that means). It is a great small tree with some of the most beautiful of all exfoliating bark so looks great in the winter landscape (see January blog with Jay Priddy).

In our nursery beds we have our finest tree lilac blooming! It is a Japanese Tree Lilac (Syringa reticulata) grown from cuttings from an old tree in my old Rockford, Illinois, neighborhood. It is the best tree lilac I have ever seen and we may need to give it a cultivar name and introduce it into the nursery trade sometime. It has huge flower clusters every year and larger than normal leaves. The parent tree is about 80 years old in the wonderful Edgewater neighborhood of Rockford, Illinois: that old neighborhood with lots of interesting trees and plantings, sidewalks, some brick streets, porches and garages along an alleyway in the back. It's what new urbanism is trying to reproduce today! I am happy a dear friend JoAnn Mercer sent cuttings of the tree and our propagator Marie Frye was able to root this plant, which is now 10 years old.

A closeup of the frothy flowers of the "Rockford" Japanese Tree Lilac. You can see the tree if you walk the road to the Chapel: its just east of the Horticulture Building. It always gets comments while in bloom.

The Innocense Mockorange (Philadelphus hybrid)is also finally in bloom and is hands down the most fragrant of our mockoranges.

Innocense Mockorange is not a very vigorous shrub but still produces a fine shrub for a border where you want to cut some flowers or enjoy its fragrance while it is in bloom and then let it blend with other shrubs through the rest of the year. Look for this shrub in the White Border of the Perennial Garden.

What a plethora of beautiful plants to experience at Powell Gardens. And this is only the tip of the iceberg in this time of a million blooms!

Mockoranges, Out of Fashion but not out of Style.

The pristine white flowers with a special, orange-blossom-like scent make the mockorange a staple of late spring flowers and fragrance in a garden. Mockoranges are currently out of fashion and much maligned by garden gurus but a season without them would be a miss!
Depicted are the flowers of the magnificent 'Snow Velvet' cultivar of the Western U.S. native mockorange (Philadelphus lewisii) "discovered" by Lewis & Clark.


Powell Gardens' Snow Velvet Mockorange can be seen below the wall south of the Cafe. It has the most showy blossoms of any of our mockoranges with a good scent too. It often has some repeat bloom through the summer.


We are lucky to display an heirloom Sweet Mockorange (Philadelphus coronarius) I obtained as a division from a shrub that is well more than 100 years old from a friend's farm near Decorah, Iowa. Sweet Mockorange was grown on many family farms across the Midwest and often persist near abandoned buildings to this day. They have the sweetest scent and bring back many fond memories. They also are a good nectar source for butterflies and insects.


The heirloom sweet mockorange is often blasted as a poor plant but this heirloom has full flowers of freshest fragrance. It makes a huge vase or fountain shaped shrub. Look for this plant south of the Visitor Center, another one is on the Island Garden.

We have other mockoranges on the grounds but none are as magnificent as these two. The cultivar 'Innocence' in the Perennial Garden's "white garden" may have the sweetest scent but is a weaker grower with marbled variegation to the leaves. The cultivar 'Belle Etoile' (on the upper edge of the Perennial Garden) is currently just budded and has purplish centers to richly fragrant blooms. There is one Missouri native species; just entering the state in its southwesternmost corner: the Downy Mockorange (Philadelphus pubescens). The Mockoranges are a taxonomist's nightmare and often defy identification to species with lots of regional variability. Who cares what they are called, enjoy their special fragrance and exquisite white flowers.