March 10, 2011

Bit-by-bit,Putting it together - My Top Perennial Garden Secrets Revealed

When choosing perennials and bulbs from catalogs, we might be missing a great color opportunity if we overlook selections based off of close-up photos or digital color. The reality is this violet Tulbahgia would seem relatively boring if not for the salmon dahlias and persimmon colored Nemesia planted with it. Try to use the tricks of the nineteenth century plein air artists when mixing colors rather than limit oneself to a single tone. Orange base hues will enhance a blue or violet scheme and make your garden sparkle with energy.

Layering bulbs perennials and annals not only extends your display period, it says that you are a professional gardener. Just look at nature. Grasses and wildflowers grow together and function as an eco system. Here in my garden, Apricot Phormium ( New Zealand Flax) grows with hardier perennial like Salvia and summer blooming bulbs underplanted into the whole scheme like these white Galtonia. This garden changes color from the early morning until sunset.

For intents and purposes, it is now spring ( after all, according to the weather man, “meterological spring’ started on March 1st.), so I’m going with it. I know it’s spring, because friends and colleagues at work are all coming to to me with their gardening questions, some even with plant lists from the nursery list I provided them, asking me if I ‘approve’. It’s a little funny, but I understand – there is actually little information out there which is reliable, and no question is a stupid question – I get it, since some bloggers might say “ go forth and be daring, there are no mistakes, just enjoy the process”. Rrrrright.

Meadows and woodlands are great places to get inspiration from, just be certain that they are virgin meadows and not weed-filled ones, and these are hard to find. They must be untouched, within virgin forests or never planted by man. Look for them in National Parks, high elevation areas and in some botanic gardens.

 I say” sure. There are mistakes you can make. And they can be expensive, or at the very least, leave you with a garden that is unexciting and visually boring. Look, we all want awesome gardens, after all, even if you are not ‘into’ gardening, a front garden  that can be seen from the street is a very public space, and everyone can see it. They can evaluate your expertise ( or lack thereof) and essentially a garden is the first  thing anyone ever sees when arriving at your home. So although you may fret over the exact color of your bathroom tile and trim color, the catnip (nepeta) that you are casually digging in along your front walk, actually holds more weight than you may think.
This meadow of grasses and wild Campanula, with clover, that I shot in Switzerland last June shows how nature plants her gardens. High elevation meadows and fields are some of the best places to become inspired since there are fewer introduced weed species.

So I am going to share some of the rules I most commonly advise my best friends to follow as they choose their plant material, and plant their gardens – experts or not. I may be a plant geek and a design geek, so I factor in the whole experience into everything I do, but even if you can’t grow a geranium, these rules will be helpful if you want great results.

1.    1. Don't Forget that Green is the Predominant Color - 
 Planning the color of your garden? Think Green. No, no, no, not as in ‘think green’, I mean the color green – literally. Remember, plants are mostly green.
It’s surprising how many people cut little pictures out of plant catalogs of close-up photos of flowers, and then assemble them as they plan a garden. Some garden designers even suggest taking colored pencils and sketching a pink shape where pink flowers will grow in a garden, and then a peach colored blob where another clump of perennials will go. The only problem is that these plants are 90 percent leaves, and more often than not, the perennial you are choosing will only be in bloom for about 2 or 3 weeks out of the growing year.
Another garden in the alps, these clumps have at least 6 plants in each one. Think this is not important? Imaging this garden replanted with only one plant per clump.

If you are planning a garden, buying seeds or perennials, you must think about the entire plant, not just the flowers on the ends of the stem. Generally speaking, you must take into account the volume of space that a plant takes up and the visual impression it has when in bloom. For example – a Nepeta ( catnip) photo in a catalog may show a beautiful tubular flower, but in real life, the plant has masses of fuzzy grey green leaves for 90% of the time, and then it has a cloud of pinkish purple tiny flowers which form a haze over the foliage. You might find the resulting planting to be rather different than what you expected, so I always advise people to test a single plant first for a year or two before deciding how many they may need in a mass-clump to create the ‘perfect effect’ ( because you will at some point, need to make the perfect effect by planting en-masse).

2.     2.  Layer Plants in the same space.
Underplant, sprinkle in, and fill gaps with other plants within a larger planting of one type. Experts know how to combine different plants together, and there is no better expert that nature, herself. Mixing plants to extend color throughout the season is what nature does, just think about woodlands and meadows. Layering for garden effect not only multiplies the interest quotient, it makes you garden look more professional. I advise friends to think of gardens as pointillist paintings ( spots of colors that all blend together when viewed from a distance). Think – Seurat. Take that wispy planting of Nepeta, a virtual lavender cloud of flowers floating over an olive green bed of foliage, and now add 35 bulbs of a gladiolus like G. imbricatus, a wild form that is more wirey, less blousy and brilliant neon violet in an unassuming way – wands of color dots that will blend with the lavender mist of the catnip. Lovely, and now you may start to not notice all of the green. But embrace the green, look for foliage that has textural interest too.

The long border at Christopher Lloyd's Great Dixter is another inspiration. This year we are adding the first phase of our version of the Great Dixter border in our back yard ( I know! Crazy, at 110 feet long). But each of these clumps of color are composed of many plants planted together. Then, the entire border in underplanted in bulbs so that from early spring until autumn, there is interest by-the-square-foot. Here, texture as well as color is important. So when you look at a canna blossom close-up in a catalog and say "I hate salmon, because it doesn't go with red" think again. These are mere dots in a much larger painting.

Garden designers call this ‘underplanting’, but it serves an important purpose – it extends the value of your real-estate – meaning that your 10 square feet of catnip that was in bloom for only a month, now provides a spectacular show for seven months. Use various bulbs, annuals and other perennials that might poke through other species, or that fill in gaps. Knowing what to choose and what to combine together is what defines the good garden designers from the best ones. And if you are not doing this, then you are going amateur all of the way and your garden will look like it.
3.     Texture and Light – this is about the angle of the sun – Really, this is why we add grasses to the perennial border. Not because they are grass, but because the foliage moves with the wind, it’s more about gestalt than it is about grassyness. Grass is completely different when viewed with back light from the sun, or on an overcast day with rain, or in the evening with the low sun streaming beams of golden light across the garden at an angle, or in the early morning.

3. Think TEXTURE - 
The human eye reads grass as a soft texture, and once it blooms, it becomes even softer. Repetition is as important as texture and how the sun reflects in the grass blossoms. Some grasses, by the end of summer, produce flowers that look like smoke because they are simply composed of tiny purplish red stems so tiny and wirey, that they capture the light and move the eye. Now, imagine 12 Panicum virgatum, pr Switch Grass plants, with steel blue foliage and violet airy mist-like flower stems behind that planting of Nepeta, stunning.
Another view of my front garden which is still a work in progress. These fuzzy Amsonia hubrechtii are currently planted with young plants in clumps of 6, but I will add 6 more this year to the planting, and then interplant them with Camassia bulbs for spring color, and species gladiolus for summer tints.

4.     4. Plant Lot's of the same Perennial together - 
Size is everything, and bigger is better – Invest in as many plants of the same variety as you can afford. Plant large numbers of plants together to create big impressions.

I say this all of the time, and although I know that few of us can afford it, the truth is that great gardens are all about numbers. Look at any well-known English garden border, and try and count the plants in each ‘clump’. Visually, at first a clump of Phlox may just look like one plant, but upon closer inspection, you will see that often there are 20 – 30 plants planted together. It’s really the only way to plant perennials and herbaceous borders. At Kew last year, I counted an average of 35 Epimediums in each planting, ( really – 35), and then layered under those ( and poking out above) were seasonal bulbs, alliums and small anemones by the hundreds. Add to that, spots of even taller perennials scattered through out as exclamation points. Always plant as many plants as you can in a single area – simple rule. I start by always ordering 6 ( not 3, it’s just no enough). Actually, I am trying to order 10 of everything, but even I can’t afford that, so I start with 5 every year and then I keep adding to the planting.



  1. Very helpful post! I do think "planting in large numbers" only really works when you have large spaces. For small home gardens it's not always practical (or affordable). Although planting 3 of the same plant is still better than 1 in many cases.

  2. Excellent post. This is great garden designing advice and I endeavor to plant by many of your suggestions.

    I love the look of mass plantings... and in a small town lot like I have it is still worth spending the space and limiting the choices to plant some really key plants.

    Appreciate your succession suggestions from Amsonia.


  3. wonderful advice...I love mixing colors that become focal points that draw your eye...I tend to plant a few and let them grow in they suddenly look like 6 in no time...or divide and move them to keep the look going...a constant never ending fun way to design and I hope others will take your sound advice


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