Louis Raymond experiments in his own gardens like

a mad scientist, searching out plants that most people have

never seen before & figuring out how to make them perform.- The Boston Globe

…Louis Raymond ensures that trees can grow in Brooklyn…

or just about any other place where concrete consumes

the dirt and skyscrapers shield the sunshine.- USA Today

 
 

NEW Trips to Take!

Myrtle's easy when the conditions are right.

 
 
 
 

NEW Plants to Try!

Louis tries to capture the exact words to describe the fleeting but deep pleasures to be found in these Summer-into-Autumn incredibles.

 
 
 
 

New Gardening to Do!

Allergic to bees? You can still have an exciting garden, full of flowers and color and wildlife.

 
 
 
 

Plant Profiles

Today in the Garden of a Lifetime: Himalayan Musk Rose in Bloom

A rose in bloom in April in New England? Outdoors, only if the season is unusually warm and the shrub is Rosa hugonis. Or, in this case, if the rose is growing in a greenhouse. This chaste beauty is Rosa brunonii 'La Mortola'. It isn't solidly hardy here, so I grow it in a large container that's moved into shelter November through April. 

 

Rosa brunonii La Mortola one flower fingers 041515 640 

 

Could these single, pure white flowers be fresher, more eager to greet the new season? Below, a shot of another of the flowers. The tight focus created the arty quick-fade of the background.

 

Rosa brunonii La Mortola solitary flower 041515 640 

 

Because the flowers are single, the buds are slender and elegant, too: There are just those five petals, not the dozens of them that would crowd within each bud of a rose whose flowers are fuller.

 

Rosa brunonii La Mortola one bud 041515 640

 

More mature bushes of 'La Mortola' form clusters of blooms with many buds, not just the three below.  

 

Rosa brunonii La Mortola three buds 041515 640

 

It's no small victory to have 'La Mortola' in flower at all when growing it in a container. This involves overwintering it frost-free, bringing it into the garden in Spring and back into shelter in Fall, while watering faithfully year-round—and throughout, keeping its lengthy, hook-spined, fragile canes gracefully in control. Yet another hurdle—still to be cleared—is to provide a combination of heat and light through the cool Winter months such that the shrub doesn't fail from severe cold, nor come into flower prematurely because the lengthening days of Spring cause surprisingly warm days in the greenhouse when it's still fatally cold outside. 

 

One of my Spring-flowering tropical trees, jacaranda, is a plant to look to for guidance on delaying flowering from April in the greenhouse to May or June in the garden. In climates where Summer comes on fast—Florida, say—jacaranda flowers in April. In climates with only a slow Spring that increases to a less intense Summer—San Diego, say—jacaranda flowers in June or even July.

 

'La Mortola' rose behaves similarly. In its native range from Afghanistan to western China, it flowers anytime from April through July depending on the elevation. Higher elevations will be cooler in Winter and Spring, and never as hot in the Summer. So the shrub ramps up more slowly during Spring's weeks of only gradually increasing warmth: It can take until July for the shrub to build up a sufficient head of steam to bring on flowering. 'La Mortola' keeps to the same performance schedule in the similarly cool and mild climate of Britain; my English rose references all say that 'La Mortola' flowers in late June or early July.

 

Can I provide a climate that's more like that of England or a mild high-elevation district of Afghanistan? Where Winter is cool but mild, and gives way only reluctantly to a Spring warmth that is, well, warm only by comparison? By Summer, it's fine for 'La Mortola' to experience the typical heat of eastern North America. The rose will have finished flowering anyway, and the higher heat will encourage more vigorous vegetative growth while also hardening it more thoroughly in advance of the next cool season.

 

Here's what I'll try: I'll allow the shrub to experience the first mild frosts of Fall, so the foliage drops and dormancy develops. Before, I had brought the shrub into shelter before frost, to keep it growing longer in the Fall and enable it to start growing sooner in late Winter. I'll also position the shrub in the cooler portion of the greenhouse, with the pot resting directly on the floor instead of being elevated, and placed nearer one of the always-draftier end-walls, not in the warmer draft-free central section. Perhaps these two steps will be enough to keep this rose from sprouting new leaves in late March, let alone forming buds. To help further, I'll move the shrub directly against that end-wall on the third week of March, when there's a diminished threat of serious cold from outside the greenhouse and, yet, solar heating during the now-longer days can bring the greenhouse to unwanted Summer-like warmth.

 

For 2015, then, these 'La Mortola' flowers will continue to be two-fold exotics: any rose at all in flower in April, let alone those of a rose that is extremely rare outside its hardiness range. For 2016, when (I hope) the rose will be in flower in June, the rarity of this rose's display will be based entirely on its aesthetic merits, not a freakish out-of-season peak. No problem: This rose's considerable gifts are both foliar and floral, and can hold their own even when most of my hardy roses are at their height of bloom.

 

Here's how to grow 'La Mortola' rose.

Here's how glorious this rose's long stems of blue foliage looked the season I allowed them to grow through my 'Silveray' pine.

 
 
FacebookTwitterRSS Feed

Stay in touch!

 

Sign up for twice-monthly eNews, plus notification of new posts:

 

* indicates required