Gardening Question of the Day for Saturday, May 24, 2008
How often should I water squash for the best crop? (answer).
From The Old Farmer's Almanac.
From The Old Farmer's Almanac.
From The Old Farmer's Almanac.
From The Old Farmer's Almanac.
It was long in coming, this interest in the genus Hydrangea. I must admit I was never really infatuated with hydrangeas. Even as a teenage gardener new to the field, I thought they seemed old-fashioned, heavy, and sat like a bunch of thick sticks in winter. These preconceived notions probably grew out of my experience with the only two species that I’d seen in my growing-up years – the Pee Gee or Panicle hydrangea (Hydrangea paniculata ‘Grandiflora’) and the mophead (a.k.a. hortensia) form of the Bigleaf hydrangea (H. macrophylla). Maybe once in a while I’d seen some untidy mass of twigs often referred to in my parents’ old Better Homes and Gardens Garden Book (1951 edition) as “Hills of Snow,” too; that was H. arborescens ‘Grandiflora’ – actually a selection of a native species with flowers arranged like mini white mopheads on suckering straw-colored stems. The Pee Gees I recall were usually pretty much overgrown, leggy, and almost tree-like fountains of deadwood when not in bloom. The mophead bigleaf types were often neglected shrubs (again with noticeable deadwood), reliably bearing huge balls of pink or blue flowers that looked really artificial when they bloomed in summer, and were found in nearly every old person’s yard. These were granny shrubs, and were not the hot horticultural fashion of the time – except at the Jersey shore, where (thanks to their appreciation for moist maritime conditions) they remain one of the few shrubs you encounter in the typical shore resort landscape.
Fast forward ten-plus years. It’s the early 1990s and I’m now working full-time at a garden center, and what are we selling in the way of hydrangeas? The ubiquitous (but hardy) bigleafs like ‘Nikko Blue’, a newer one called ‘Preziosa’ (with reddish stems), and a ton of ‘Mariesii Variegata’ (which hardly blooms, but the silver-edged foliage is the selling point). Oh, and for Easter or Mother’s Day, we would have all those greenhouse-forced hydrangeas with the really shiny leaves and one or two huge, unwieldy, usually pink mophead-type blooms that are never to be seen again, because (we explain to the customer if we are honest) these are not fully wood-hardy here in zone 6. (I consider these “gift plants” more like “punishment plants” because I figure a lot of folks give them to mom, and then mom is forever perplexed that her hydrangea generates really shiny big leaves every summer but just never blooms. Now, is that nice?)
But wait, at the same time retailers are carrying only the old standard mopheads and maybe a few Pee Gees, there emerges something “new” in the land of cutting-edge horticulture – the “lacecap” hydrangea. And the native (well, native to the southeastern U.S.) Oakleaf hydrangea (H. quercifolia) – a hydrangea that boasts four seasons of interest (gray-green new growth as it emerges in spring, early summer cones of creamy white bracts, fall foliage in shades of burgundy and orange, and winter stems exfoliating in cinnamon-color strips)! The scuttlebutt was that Martha Stewart was behind all the sudden requests we were getting for Pee Gees, and that she had rekindled the interest in drying the panicles and mopheads for decoration.
Around 1993 – not long after the Pennsylvania Horticultural Society awarded a Gold Medal to Hydrangea ‘Blue Billow’ – I decided to buy three of these from a small mail order nursery, and plant them in our typically acid soil (in what I hoped was the appropriate moist and partially-shaded site). These were the first hydrangeas ever to grace my parents’ yard in its nearly forty years of existence. I happily report fifteen years later the three ‘Blue Billow’ – a serrata type – have never failed to bloom every July, covered in inflorescences made up of solid-blue, tasteful fertile flowers that are surrounded by the sterile (but showy) deep-wedgewood-blue clover-like bracts, although the leaves do “flag” or wilt plaintively during any dry stretch of weather – as all macrophylla relatives are wont to do.
In the last ten years, the selection of hydrangeas has just exploded – especially if you shop via mail order or by web. Maybe, for much of this we can thank Dr. Michael Dirr – the dean of woody plant horticulture in the eastern U.S. and a major exponent of hydrangeas. Just count all the cultivars of the Pee Gee types and the ever-growing selection of oakleafs (‘Little Honey’ is a dwarf form with bright yellow new leaves, among so many other recent introductions), and the popularity of ‘Annabelle’ – which single-handedly brought H. arborescens back from the brink! Now that I’m working here at Fordhook Farm, I am immersed in the exotica that come from Heronswood, and (obvious to any seasoned customer) this indeed is the place to experience hydrangeas in all their nuances. In this case familiarity breeds not contempt but appreciation: You get to see the fourteen different lacecaps and sixteen mophead selections of Hydrangea macrophylla currently offered by Heronswood, to - get this – eighteen selections of H. serrata, a form that only twenty years ago you would be hard-pressed to find in the trade. Where did all those different kinds of showy bracts come from? Judging by the cultivar names (such as ‘Midoriboshi Temari’ or ‘Izu-no-Hana’ or ‘Beni-Gaku’ or ‘Kyosumi’), the Japanese have been selecting these related species for a while. (I really need an interpreter, though, for I hear a name or two translated and they are pretty descriptive – in a very poetic way – and this really helps me differentiate one from another.) Until now, I had no idea the uncommon-in-these-parts H. aspera types – with their huge lacecaps made up of prominently mounded fertile flower centers (ignoring the really tall and leggy habit of the plant) – could be grown in the eastern U.S. (solid zone 7, but pushing it in zone 6). The first time this species came to my attention had been during my first visit to England about ten years ago.
Last summer, I visited the Seine-Maritime region of Normandy, France. (http://www.greaterphiladelphiagardens.org/column.asp?ColumnID=45) I and my companions soon realized it must be the ideal climate for what the French refer to collectively as Hortensias (any member of the genus Hydrangea), because everywhere you go, there has to be at least one in every garden. One of the gardens on our itinerary had the unlikely name “Shamrock” and turned out to be one of the largest collections of hydrangea in the world (http://www.hortensias-hydrangea.com/). There at the small ticket booth as we entered was the proprietor himself, Robert Mallet. Over the past two decades his wife, Corinne, created this garden specifically for hydrangeas. I come to learn that Corinne Mallet authored two books on the genus (Hydrangeas: Species and Cultivars, vols. 1 and 2). Truly a hydrangeologist (if there is such a term), Mrs. Mallet had traveled to Japan to study under the preeminent authority on this genus, Takeomi Yamamoto. In only four acres, they now have 2000 hydrangeas planted for research. Now that I am working with Heronswood, I draw the connection between its history of collection and selection, and the research that continues here at Fordhook, with the work being done by the Mallets in France.
Mr. Mallet generously gave us his time – and a signed copy of one of their books. It really is inspiring, this bond among gardeners. The generosity of people who love plants is amazing – shared not just neighbor to neighbor but often from country to country, across continents and oceans.
first published May 15, 2008
Do yourself a favour and take a two-week vacation. No, I’m not suggesting you hop on a plane and leave the country, although I’m sure many of you would jump at the chance. What I’m talking about is seeking out areas of the city that are loaded with spring-flowering trees and shrubs and making a two-week habit of walking around and enjoying their beauty and fragrance.
Spring-flowering trees and shrubs have the same floral development pattern no matter where you find them in the world. The buds burst open in the summer and desperately try to attract pollinating insects before the petals deteriorate and fall to the ground. The display is incredible, but ephemeral, and lasts only a few weeks. But like vacations that are never quite long enough, spring blooms are another short-lived indulgence that you just wouldn’t want to give up.

There are a couple of fundamental differences between trees and shrubs that flower in the spring and those that flower in the summer. Spring bloomers develop their flowerbuds in the summer and fall prior to the spring blooming season. For example, flowering plums develop mature flowerbuds by midsummer but require several months of winter and a few weeks of warm weather the following spring before they will burst into flower. Summer-flowering trees and shrubs develop their flowerbuds on the current season’s growth. For example, the rose flowers that develop in spring of 2008 were grown from scratch on the leafy shoots that emerged from the canes in 2008. Because it takes summer-flowering plants several weeks in late spring to develop leafy shoots and then a bud, they typically bloom after June 20th, whereas spring-flowering shrubs bloom prior to June 20th.
Even though spring-flowering trees and shrubs are at their peak for only a few weeks, you can maximize the duration of the spring blooming season by choosing plants that bloom at different times—some in early spring, some in midspring, some in late spring. If you like the idea of planting successive spring-bloomers, here are a few that should provide you with a blooming continuum from May and right through to the third week of June.
Forsythia

One of the earliest blooming shrubs on the prairies, producing a spectacular display of bright-yellow flowers that emerge prior to leaf formation. Plant in a sheltered site to prevent harsh winter weather from killing the flower buds. It’s a true harbinger of spring. Height: 2–3 m; width: 2–3 m.
Muckle Plum

The extravagant, rosy-pink floral display of this short, slow-growing shrub comes hot on the heels of forsythia. Muckle plums are available as large shrubs or as small trees, making them a great choice for any sized yard. It is also sterile and, therefore, won’t produce fruit. Height: 3–4 m; width: 3–3.5 m.
Double Flowering Plum
Irresistible in full bloom. One of the first shrubs to bloom in spring, its leafless branches are covered with showy rose-pink, double blooms, each nearly 4 cm across. Does not bear fruit, making it a tidy choice for along walkways or decks. Height: 2 m; width: 2 m.
Ornamental Flowering Crabapple
These trees are simply breathtaking in full bloom. Grown for their decorative (rather than edible) fruit, ornamental crabapples are all about blossoms, form and foliage. ‘Spring Snow’ is a particularly nice, midspring blooming variety, producing bright-white, fragrant blossoms but no fruit, making it a perfect choice for planting near a deck or patio. Height: 8 m; width: 6 m.
Hawthorn
Hawthorns are beautiful, compact trees with fragrant flowers, bright-green leaves and sparse red fruit—a perfect choice for a small space. ‘Toba’ has fragrant, double white blooms in midspring that age to rose pink. Height: 6 m; width: 6 m
Dwarf Korean Lilac

This is the consummate spring flowering shrub in our region. It blooms dependably and boldly and has outstanding fragrance. Dwarf Korean lilac has red-purple buds that open to pink in late spring. Makes a great small hedge plant. Height: 1–2 m; width: 1.5–2 m.
The rules for planting spring-flowering trees and shrubs are simple. Choose a sheltered spot that receives full sun, and dig a $100 hole. In other words, you’ve spent money on the tree, so make the planting hole worthy of it. For optimum root growth, make the hole the same height and three times as wide as the rootball, and ensure that the backfill soil is a good-quality loam.
If you don’t have any spring-flowering shrubs or trees in your yard and don’t plan on growing any, my suggestion is to invest in a good pair of shoes and find the spots in your city that are bursting with blooms. Take my word for it; it will be the most inexpensive holiday that you’ll ever take and likely one of the best.
Believe it or not some plants show their true colors when they are pot bound and the brilliant colored Bougainvillea is just one of those special plants. Bougainvillea will put on their best flower show when they are a little tight in the pots.
Here’s a tip from Kellie Pilier who specializes in growing Bougainvilleas for the landscape trade.
When they are planted in the landscape leave the plant in the growing container. Here’s how to plant them this way.
Carefully cut out the whole bottom of the pot. If that seems too difficult then cut some large holes about the size of a grapefruit around the whole pot.
Some landscapers simply cut large slits down the side of the pot. The downside of this is that sometimes the roots can be pinched and become weak.
Taking the time to cut holes in the pot will require the most time and effort but it will give the best blooming results.
More Boug tips soon - but for now Here’s more on Bougainvillea Care
