Rhododendron & Azalea News

Rhododendron and
Azalea News

Summer/Fall 2008 Vol. 11 No. 2/3

ARS Home Page R&A Index Plant Tips People and Events Ideas for Chapters

Gardens
Companion plants...bottle brush		Fothergilla (the bottle brush plant or witch alder) is a deciduous, low-growing shrub closely related to the Witch hazel (hamamelis). They have showy, honey-scented, brush-like spikes of white flowers in spring. Their leaves turn a beautiful mix of yellow, orange, and red in the fall.
three species...		There are only three species of Fothergilla. All are native of the Southeastern United States. All of them are wonderful shrubs for the mixed border or rhododendron garden. The three species are: gardenii, major, and monticola. Fothergilla gardenii (Dwarf Wiutch Alder) grows about 4 ft. tall. Fothergilla major (Large or Mountain Witch Alder) is a much bigger shrub capable of reaching 10 ft. tall and wide. Fothergilla monticola (Witch Alder) reaches 3 to 4 ft tall and wide.
species named for...		The Fothergillas are named for Quaker John Fothergill, a physician and gardener in 18th Century London. He funded the travels of William Bartram (America's first native born naturalist). William Bartram made scientific observations of plants in a journey that took him from the foothills of the Appalachian mountains to Florida, through the southeastern interior all the way to the Mississippi River. The species Fothergilla gardenii was named in honor of Dr. Alexander Garden, who was among John Fothergill's many correspondents. Dr. Garden was a Scottish physician and botanist who lived in South Carolina, where he first spied the shrub in 1765. The Gardenia from Asia had been named earlier for Dr. Garden in 1761.
characteristics...		The Fothergilla's tightly clustered yellow and white strongly scented flower spikes begin the show in April or May and persist for 2-3 weeks. The flowers have no petals and the parts that look like petals are actually stamens. The green leaves appear after the flowers...and have great fall color.
place they love to grow...		Fothergillas flower best when they are grown in full sun. They develop more intense autumn colors when they get plenty of sunshine. Fothergillas are highly adaptable and will thrive in partial shade. They will sucker at the base quite freely. Branches can be layered to produce new plants. Fothergillas prefer a moist, acidic, fertile, well-drained soil. Little pruning is needed other than an occasional thinning of older branches.
Mt. Airy is preferable choice...		The form of Fothergilla gardinii called ‘Mt. Airy’ (also listed as 'Mount Airy') is widely considered to be the finest selection available. All attributes of this form appear superior, including larger flowers, clean blue-green foliage, strong fall color (yellow to red), and vigorous upright growth habit to 6 ft. tall. Mount Airy Fothergilla is a hybrid of Fothergilla gardenii and Fothergilla major. 'Mt. Airy' is widely available and, probably, should be chosen over other forms. - Garth Wedemire

Up the garden path with Christmas holly		Norma Senn of the Fraser South Chapter writes the most interesting articles...and so many of them are timed to the season. We are getting close to the Christmas season so it seems appropriate to learn some of the Christmas holly. Holly has been used to decorate European homes since Druid times. Over the centuries and with the advent of Christianity, many associations have developed concerning holly decorations at Christmas time.
legends behind symbols are interesting...		Why, some readers might wonder, do the words of the title for these comments appear together and how do they relate to one another in the context of our Eugene Chapter. We shall see, we shall see...but not right away as a few twists and turns unfold before getting to the point.
holly is prized for other things, too...		In addition to their decorative use at Christmas time, hollies are prized by carpenters for their fine, dense wood. Leaves from some holly species have been used to make tea, and their flowers are very attractive to bees, yielding fine honey. Where they are hardy, they also make lovely large specimen trees in the landscape. We are most familiar with the red-berried varieties, but there are also very attractive orange- and yellow-fruited hollies. Commercial holly sold by florists at Christmas time is harvested from Ilex aquifioilium, the English holly. In Canada, commercial holly orchards are located in the mildest areas of British Columbia, most are on Vancouver Island...but there are a few orchards in the lower Fraser Valley. English holly is best grown in fertile, deep, slightly acid soils that have good drainage. They like moderate growing temperatures, neither very hot...nor very cold...and even moisture is required throughout the growing season.
growing habits...		It takes eight to ten years after planting before the trees are large enough to start harvesting, and often plants are 15 years old before major harvesting begins. Commercial growers want to know the exact characteristics of the holly they grow, so typically they plant grafted plants or plants that were started from cuttings. Growers play a guessing game in selecting varieties for future harvesting. They have to predict what will be fashionable in the florist trade in a decade's time. I remember talking to a commercial grower who was trying to decide whether or not he should top-graft his green-leafed holly trees to change them over to variegated types because of the rising trend towards the use of more variegated plants. He had planted most solid green forms which at the time of planting were what the florist trade preferred. As well, growers have to decide on the number of prickly-leaved or smooth-leaved varieties to plant.
other decisions for growers to make...		Another decision to make at planting is to balance the number of male to female plants in an orchard. Most English holly is dioecious, that is, some plants are male and have only staminate flowers that provide pollen, and other plants are female and have pistillate flowers. In order for berries to form on the female trees, pollen has to be transferred from the staminate to the pistillate flowers. A ratio of about one male tree to every fifty to sixty female trees is commonly planted in large commercial orchards, but this ratio can vary tremendously depending on the size of the planting. For home growers, if berries are wanted on English hollies, care must be taken to plant both a female and a male tree. Watch for the identifying tags on plants in the garden centers that tell you which plants are male and which are female. Happily, there are now some holly varieties that have perfect flowers, so berries will be borne in a single tree. Growers are paid based on the weight and quality of a crop. Good berry set adds to the weight, so growers want a balance of berried branches to leafy branches in order to make the most money. Of course, the overall quality of the leaves and the ratio of variegated and dark green leaves also determine the crops’ value.
delicate handling...		Holly is cut by hand in late November. the branches have to be handled carefully to avoid having the prickly leaves physically damage other leaves, and to prevent knocking off the berries. After cutting, holly is washed to rid the leaves of algae or dirt. The leaves are also inspected for obvious damaged areas and any individual leaves with leaf miner spots or other blemishes are removed. For floral arrangement we want the berries to stay on the branches as long as possible...but once holly is cut, the berries start falling off. To prevent both premature berry drop and leaf discoloration, many growers dip cut holly branches in a weak solution of naphthalene acetic acid. This material is related to the naturally occurring auxin compound found in plants, and it can prolong the useful life of cut holly by several weeks. After dipping, the branches are allowed to partially air dry...and then are boxed for shipping. Garden centers sometimes sell a holly dip product for homeowners.
tips for floral arrangements...		re-cut the stem ends using sharp shears. Try to make the cuts on the diagonal to expose as much wood as possible to the water. make sure the arrangements have ample fresh water, or if oasis is used, it should be kept well-moistened at all times. arrangements will last longer if they are kept in a cool location. well-conditioned holly should last for at least three weeks, if kept cool. for holly wreaths or other outdoor decorations, the cool weather helps to preserve their appearance. If exposed to very cold weather, the berries will freeze and as they thaw, they turn black. To prolong the life of your wreath, if possible, keep it in a protected location, for example, between a main door and the storm door. Enjoy your Christmas holly...Enjoy in the house...Enjoy outside, too!

W is for Weigela...a companion plant		Once the main splash of rhododendrons is over, there is a charming group of plants that fills the color gaps in our landscapes...quite nicely. Named after a German botanist, C. E. von Weigel, the Cardinal Flowers (Zone 4 and 5) are deciduous shrubs of open woodland areas in parts of Asao...which have a multitude of foliage and flower features. Most of our available varieties are selections or hybrids of two species: W. florida and W. praecox, although the wild forms are rarely offered. The blooms, in May and June, are tubular, in small clusters along older stems, often with nicely contrasting stamens. In blossom, they attract hummingbirds by the flock.
the "in" color is purple....		The "in" thing these days among plant introducers is purple leaves, starting back with 'Foiliis Purpureis' ('Java Red')...on to 'Victoria', then 'Wine and Roses' ('Alexandra'), 'Ruby Queen', and now 'Midnight Wine'! The color is getting darker, and the plant habit is getting smaller...what's next...a black groundcover Weigela? Attractive and useful plants nevertheless...most of them have pink to bright pink blooms. The 'Dance Series', developed by Agriculture Canada, have all been selected for very compact habits, extra hardiness, and richly colored blooms. Foliage variations are from green to burgundy, with deep pink or red blooms. Look for 'Tango', 'Polka', 'Samba', 'Rumba' and 'Minuet'.
gold-leafed forms are finicky...		Gold-leafed forms are a bit more finicky...they need partial shade to avoid foliage burn...but too much shade makes them go green...so it's a fine line. 'Looymansii Aurea' has pale pink blooms, while the newer 'Briant Rubidor' (aka 'Olympiade' or 'Golden Ruby') has dark ruby flowers that offer a striking contrast. Variegated leaves, with cream to light yellow margins, occur in both species, and have pink flowers. The variegated areas take on rich pink to red tones in fall, for extra punch.
white-flowered forms may be ok...		White-flowered forms are available as 'Bristol Snowflake', 'Candida', 'Mont Blanc', and others...but I must admit I don't really care for them...although 'Mont Blanc' is highly rated. Possibly I just haven't seen one at the right stage or in the right setting. A new introduction, 'Carnaval', has blooms of white and two shades of pink all at once on the same plant. That's kind of neat! For deep red, the old 'Bristol Ruby' and 'Eva Rathke', although good and reliable, have been superseded by newer, tidier, non-fading varieties like 'Red Prince', 'Lucifer', and the even smaller 'Nain Rouge'.
Weigela's characteristics...		Weigelas grow easily in any well-drained moderate soil...and old bloomed-out stems can be cut to the ground to allow new ones to take their place. Trim right after blossoming in the early summer to keep leggy branches in order, and to give time for the wood ripen and set bloom for next year. Some varieties will bloom off and on throughout the summer, and other appear in early summer and again in early fall. Two unusual species, W. middendorffiana and W. maximowiczii, have light yellow flowers in late spring...most "un-weigela-like", but truthfully I have not seen either offered for sale locally. Good on you if you can fine one! Look around in the plant centers when you've gotten all your beddings settled and your rhodos are on the wane...and you'll find one of these to be a delightful addition to your garden...big or small! Happy Planting! Colleen Forster of the Fraser South Chapter has done it again! Thanks, Colleen, for your continual sharing of your love for nature. You always bring so much meaning into your articles.

A word to the wise.		The happiest person is the person who thinks the most interesting thoughts, and we grow happier as we grow older.