Tag Archives: mixed borders

Tikorangi Notes: underplanting, gardening with perennials and the magnificent nuttalliis

Pretty Rhododendron Yvonne Scott (nuttallii x lindleyi x dalhousiae) with a named clematis but I have lost its name – relevant to the last para on this post and a prettier photo to lead with than the mishmash of a garden bed below 

Not good at all. The addition of roses was a particularly ill-considered decision

I spent a good four or maybe five days taking this unsuccessful garden bed apart. It was first planted about 14 years ago and the original idea was that it continue the theme of the driveway border – mixed shrubs with predominantly hellebores as underplanting. It has never thrived and over the years, its treatment has followed a pattern that many will recognise – random attempts to spark it up that have made it messier and more disjointed.

I lifted everything except the Queen palm (Syagrus romanzoffiana), an attractive Viburnum sargentii ‘Onondaga’ and Camellia minutiflora. The location is too sunny for the hellebores and they were not thriving, so I planted them elsewhere. And I found why the plants at one end had never thrived. I could only get the spade half way in before I hit what might as well be bedrock. It was the old driveway with very heavily compacted road metal. I recalled that Mark had got the nursery staff to plant that bed when it first went in. Now, our nursery staff were whizzybang at speed-potting plants and doing the hard graft of keeping a production nursery going but gardeners, they were not. I am guessing they chiselled holes just large enough to fit the plants in. No wonder so many failed to thrive. There was nowhere for them to get their roots down.

The aim is to have a carpet of harmonious under planting by the end of summer

I took out any larger stones and rocks I could get out, dug the soil and incorporated compost at a rate of a small barrow-load per square metre. There is still not a great depth of soil but what is there should be better and I won’t try growing any more deeper-rooted plants at that end. When it came to choosing what to replant, I fell back on my mixed border philosophy. When there is a mixture of shrubs in the upper layer, it is better to choose some uniformity in the ground cover layer. The opposite is also true: where there is uniformity in the upper layer of shrubs and trees, it is more interesting to use a mixture of plants at the ground level. It may be a sweeping statement (well, it is) to say that only landscapers, non-gardeners and novices go for regimented simplicity of matching upper layer plants and a single choice ground cover – tidy, visually effective in the immediate stage but essentially dull.

A totally reliable stoeksia that is particularly amenable to being divided and transplanted

Given the feature shrubs and palm are interesting in their own right and the presence of assorted seasonal bulbs, I chose to replant at ground level with the reliable, long flowering blue stokesia which thrives with us, a ground-hugging blue campanula and two forms of our native brown carex grass.  The upright form is Carex buchananii , I think, but I am not sure what the fountaining version of it is called. They are to form the carpet. I like the combination of blue and the mid-brown carex. Then I mulched it all. Now all it has to do is to grow.

May 2019

November 2019

It is quite gratifying to see how much the grass garden has grown since I planted it at the end of May. I am hoping that it will have closed up quite a bit by the time autumn comes. There have only been a small number of deaths amongst the plants – all were  Astelia chathamica and fortunately, I have more plants to hand that I can move to the gaps. The advice from colder climates is not to move perennials in winter because they are not growing and the risk is that the roots will rot out over winter. With our mild winters, this advice does not generally apply here but that may be the case with the astelia. The divisions all had roots when they went in but it may be that some did indeed just rot out before they came back into growth in spring.

My main task in this new garden is staying on top of the weeds. Considering it is new ground, there is not a big weed problem at all and I am determined to keep it that way as it gets established. Weeds getting a hold amongst the fibrous roots systems of perennials and grasses can be a maintenance nightmare. It is better by far to keep them out from the start, as far as humanly possible. Because it is all ground that has been freshly dug this year, it is easy to hand pull those pesky weeds that do try and make an appearance.

Eighteen months to fill in seems a quick result

Even more rewarding is to see the caterpillar garden hitting its stride – nicely filled out, floriferous already, weed-free and colour-toned as I want it. It has taken about eighteen months to get it to this stage. Gardening with perennials is very different to gardening with trees and shrubs. As long as you have plenty of divisions and the ground is well-prepared, the plants can rocket away and fill spaces quickly.

Species selection of R. sino nuttallii, singled out for its unusual pink flush

However, no perennial can compete with the sheer magnificence and stature of the nuttallii rhododendrons that flower for us at this time of the year. These are not often commercially available – at least not the sino nuttallii species. You may sometimes find some of the hybrids around that are nuttallii crossed with lindleyi, sometimes with the addition of dalhousiae. If you find ‘White Waves’ on offer in New Zealand, it is proving to be one of the best of the hybrids we grow – reliable and a good survivor as well as very showy indeed. “Mi Amor’ is also available for sale. The hybrids have smaller leaves than the nuttallii species and are not all as strongly scented  but you may just have to take what you can find if you want to try growing these choice rhododendrons.

Rhododendron nuttallii x sino nuttallii – so the Tibetan form crossed with the showier Chinese form




Tikorangi Notes: Friday June 1, 2012

A true blue verbascum - Blue Lagoon (Photo: Thompson and Morgan)

A true blue verbascum – Blue Lagoon (Photo: Thompson and Morgan)

Latest posts: June 1, 2012
1) Astoundingly, a blue as blue verbascum. Currently only available in the UK, as far as I know, but we seriously covet it for our garden. Abbie’s column.
2) The last nerine for the season, N. bowdenii, standing up to late autumn with brazen pinkness.
3) Grow it yourself – a bay tree. It is easy.
4) And, nothing to do with gardening, but a slew of new reviews on http://runningfurs.com – children’s books this time (mostly picture books) with three really good ones amongst them.

After last week’s column about reviewing our mixed borders, I have been having such fun reworking some of the borders. But I think my concept (and practice) of unifying the underplantings is on a somewhat different page to that of the author, Anne Wareham, who motivated me in this direction. True, in one border, I drifted the blue corydalis, yellow polyanthus and blue lobelia, but also retained the Rodgersia aesculifolia and Mark’s showy arisaemea hybrids. I cast out the dreadful mondo grass which seems to inveigling its way in everywhere (compost heaps are so useful) and figured that the interesting Manfreda maculosa would be better being interesting somewhere else. Same with the burgundy eucomis and a few other plants. But I was always bound to fall off the simplifying wagon. It being the coldest border we have in the upper gardens, I simply could not resist trying some meconopsis (blue Himalayan poppies) to see if they would like the spot. Ditto, some Higo iris, because we are looking for the right conditions for these.

The proof of the pudding is in the eating. We will see how my border looks in the spring and then for the next two or three years. There is little dross left but I realise it is just not in my nature (nor, indeed, in Mark’s) to switch to simple, unified plantings. We just have to work harder at getting the combinations better and establishing different looks so they don’t all start to meld and look the same.

Reviewing our mixed borders

The Ligularia reniformis were gratifyingly responsive to being dug and divided

The Ligularia reniformis were gratifyingly responsive to being dug and divided

Because I garden extensively, I have a lot of thinking time. Not for me the IPod and little headphones to fill the solitary quietness. I prefer to hear the birds and be aware of all my surroundings while I talk to myself and ponder.

My thinking this week has been coloured by a book I am reading. You will have to wait a little longer for the full discourse on “The Bad Tempered Gardener” by Anne Wareham. I am still digesting the contents but it has certainly focussed my attention on some of my least favourite areas of our garden. I had figured that in one area, the fact that I didn’t enjoy gardening it at all was an indication that all was not well there.

What got me thinking was the oft repeated message in the book that it was better to keep to a more limited plant selection and to shun the bits and bobs effect of one of this and one of that. This particular viewpoint is so much at odds with a great deal that I have written that it has taken some reconciling. I have often bemoaned the boring and limited planting schemes of so many New Zealand gardens and the simple fact is that neither Mark nor I have any interest at all in visiting a garden with a totally restrained use of a very limited number of different plants. Similarly, I have been critical of the ever diminishing range of plants on offer to the home gardener as nurseries continue to refine their production. To us, a garden that is all form and no plant interest is boring. To the author of this book, a garden that is all plant interest and no form is just as bad.

As always, the answer lies somewhere in the middle. And that was what led me to A Revelation. The messy borders and beds I dislike maintaining and sometimes find myself walking past with eyes averted, are frankly messy beds with too many bits and bobs at ground level. The underplanting, in other words. Too often there has been a gap so I have tucked something in to fill the space – and ain’t that the way many of us garden? And all these areas are mixed borders.

The combination of Siberian iris and Bergenia ciliata works very well

The combination of Siberian iris and Bergenia ciliata works very well

Mixed borders are by far the most common method of gardening – planting woody shrubs, maybe trees, and underplanting with herbaceous material and bulbs. I am not a huge fan of this style of gardening, though we have plenty of examples here. They are probably the least successful areas of our garden. But the remedy, I think, lies in revamping that bottom layer of mostly herbaceous material and getting more unity and harmony in managing the combinations.

Not carpet bedding. It is only a short step up the social scale from bedding plants on roundabouts to carpet bedding nepeta (catmint) beneath your roses, or swathes of uninterrupted mondo grass around your topiaried bay trees. It is just as utility and unimaginative, merely in better taste than marigolds.

That is where my thinking, coming from the other end of the spectrum to the author, met up with hers. The magic is in the plant combinations. If you are going to narrow your plant selection, it matters a great deal more which ones you choose and how you put them together.

I am revisiting my intense dislike of mass plantings. I realise now that my out of hand dismissal had much to do with all those Bright Young Landscapers who dominated the garden scene in this country in the decade through to the global financial downturn. Often with big budgets and other people’s gardens, they rejected plantsmanship in favour of form. Lacking any technical knowledge of plants themselves, or indeed any interest in plants beyond their role as soft furnishings, they claimed superior status as they used some of the dullest plants on earth to create gardens which ideally looked the same for twelve months of the year.

The hallmark of good gardens, in my opinion, is the ability to combine both form and detail, which involves thoughtful and original plant combinations. They don’t all have to be wildly unusual plants. One of my successful recent efforts was a cold corner where I used Bergenia ciliata (that is the one with big hairy leaves and pink and white flowers in spring) with deep blue siberian irises. It is unusually restrained for me, but the combination of the narrow upright leaves of the iris and the large but low foliage of the bergenia looks good even without flowers. I hasten to add, I only have about six square metres of this planting. Had I done the entire length of the border the same, it would have been over forty square metres and that I would have found extremely dull.

The same principle of contrast applies to an area where I dug and divided Ligularia reniformis (that is the enormously popular tractor seat ligularia). It was so grateful it romped away and stands large, lush and over a metre tall. With a backdrop of a common plectranthus which has pretty lilac flowers at this time and interplanted with the narrow, upright neomarica, it is simple but pleasing to the eye.

Now my mind is focussed on the messy borders that don’t work. I am pretty sure that if I refine the bottom layer of plantings, that will set off the upper layers. I can’t wait to start.

First up for a revamp

First up for a revamp

First published in the Waikato Times and reprinted here with their permission.

The myth of the mixed border

A typical type of mixed border with boundary hedge behind

A typical type of mixed border with boundary hedge behind

Just at the moment I am somewhat fed up with mixed borders, or mixed beds for that matter. I am of the opinion that it is a myth that the mixed border is easier to maintain than the herbaceous border. It is easier to leave alone, but not to maintain.

The mixed border is a term coined to describe plantings which are typically a blend of small shrubs, perennials and annuals all frothing together to create a picture of flowers and foliage. It is pretty much how most people garden, certainly in freshly planted situations. The woody shrubs give year round structure often with the bonus of seasonal flowering while the clumping perennials and showy annuals fill in the spaces between and give a well furnished look, usually with the attribute of prolonged flowering. The calibre of the plant combinations speaks volumes about the skill and experience of the gardener.

This is also the face of the modern rose garden. Gone are the designated rose beds where there were only roses planted in well cultivated but bare soil with plenty of air movement – utility, lacking in aesthetics but a practical approach to growing these thorny, disease prone plants with fantastic flowers. Nowadays we generally integrate roses into mixed plantings which have a fair debt in history to the chocolate box English cottage garden. Most rose plants are not attractive in their own right so the mixed plantings mask the ugly bushes and, commonly, the diseased foliage while allowing the flowers to star.

So you plant a mixed border or bed and it looks perhaps a little new and bare in its first year, good in its second year, possibly even fantastic in its third year and then, imperceptibly, season by season, it changes over the subsequent years to the point it all becomes a little blah. The woody plants grow and start to dominate while at the lower level, it is survival of the fittest amongst the perennials. Anything rare or choice is by definition not a plant thug so will give up the fight and disappear quickly. Besides, the establishment of the woody plants is likely to have changed the micro climate and that will be compounded exponentially if you also enclosed your bed or border in a nice little hedge. Soon the well cultivated, freshly dug soil and open, airy, sunny conditions that your perennials loved has become compacted and congested with competing root masses from the woody plants, not to mention growing areas of shade.

This is the voice of experience here. I have been micro gardening the area we loosely refer to as the rose garden. By micro gardening, I mean taking apart as much as I can of the whole area and reassessing the role of every single plant. Because we also garden extensively with bulbs, there are limited times of the year when we can take apart a garden to recultivate and replant in this manner. As well as the roses, I had planted dwarf camellias for winter interest and all year round form and the site demanded a carpet of low growing perennials and annuals below. Said carpet had been looking a little moth eaten for some time – too many holes I had attempted to plug (or darn). In fact it all looked rather tired and messy. Successive applications of mulch had raised the soil levels above the surrounding edgings, compounded by the escalating invasion of masses of fine roots from an avenue of huge trees some distance away.

I am so over roses. Every time I turn around or move, I seem to get snagged on their thorns. There are times this week when I have contemplated pulling out and burning all but the standard roses. It is only the memory of their stunning November display that has given them a stay of execution. That, and the feeling that a complete garden includes at least some roses. I certainly will not be wanting to use roses extensively in any future mixed plantings.

Painful irritant though the roses are, they are not the major problem of the mixed border. It is what goes on below the ground that is the inherent structural weakness of the concept. We only view what happens above the ground but that is entirely contingent on the roots below. And the problem is that perennials and annuals are not particularly compatible with many woody plants. The latter determinedly extend their roots and prefer to be left undisturbed. In fact they can get downright touchy if you do too much poking around in their root zone. Whereas clumping plants like perennials and indeed all annuals much prefer extremely well cultivated, friable soil along frequent lifting and dividing of the former. Long term they are mutually exclusive plant families and it is the permanent roots of the woody plants which will dominate. In fact, the mixed border concept is a garden solution for the short to mid term only. In the long term, the bottom story planting of perennials goes into decline, only the tough thugs survive and it gets increasingly difficult to maintain suitable conditions even for them.

The classic herbaceous border is seen as extremely labour intensive and accordingly admired but shunned by most gardeners in this day and age when we lack legions of loyal, hardworking, devoted minions to do our bidding in the garden. Herbaceous plants are those leafy, clumping plants without woody stems and trunks and they tend to be seasonal. In fact many, such as hostas and asters, go dormant and disappear over winter. As I micro garden our mixed plantings in the rose garden area, I am thinking to myself that the digging, dividing and replanting that is the key to a good herbaceous border is not necessarily to be feared and it would be a great deal easier if there were no woody plants (and definitely no roses) in amongst them. No bulbs either. There are other places in the garden for bulbs but they don’t exist that happily in areas where you are forever plunging the spade into the soil to keep it friable and to lift plants for dividing. I have stumbled on rather too many by severing them in half.

Using hedges as a backdrop or as an edging is also problematic. At Great Dixter in the south east of England, Christopher Lloyd paid tribute to his father’s foresight in establishing a solid barrier below ground at the time when he planted the yews which are now major topiary features and hedging in that garden. It is more likely that Lloyd Senior had a man in to do it, but such long term vision stops the problem of competing roots. This sort of below ground barrier is recommended when planting invasive bamboos but I have not seen it done as a matter of course in this country with hedges. It makes sense if you garden with a long term view in mind even if it requires considerable effort in the establishment stages. You need to make sure that the barrier is far enough away to allow the hedge roots sufficient space or you will end up with poor, stunted and yellowed specimens.

If you want to reduce the amount of maintenance your garden requires to keep it looking good, turn to the shrubbery concept in preference to the mixed border and reconsider the role played by dinky little edging hedges beloved by gardeners throughout the country. What these do is give a sharp line, a definition which can also be achieved by the use of pavers, hard edges or even a low wall. None of these alternatives will cause problems with their roots, require clipping or suffer from the dreaded buxus blight.