Tag Archives: Rhododendron sino nuttallii

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

 

 

 

The October Garden

The glory of the sino nuttallii rhododendrons

The glory of the sino nuttallii rhododendrons

Floral Legacy in bud

Floral Legacy in bud

Rhododendons may no longer be the elite fashion item they were for so many decades, but we still love them.

When we started in the plant business back in the early 80s, rhododendrons were a hot ticket item. We were but one of several rhododendron nurseries in Taranaki and to survive, we needed to find our own niche. To this end, we grew a different range, specialising in varieties that would perform well in warmer climates – like Auckland. After all, even back then, one in four New Zealanders lived in greater Auckland and we figured that if we were going to sell them rhododendrons, we might as well sell them ones that would do better for them. Mark’s father just happened to have done some breeding to find varieties that were more resistant to thrips, didn’t get that burned and crispy edging to their foliage and were predominantly fragrant as well as floriferous. It gave us a good place to start.

Nowadays there are no specialist rhododendron growers in Taranaki at all and the demand has melted away. I no longer have to try and convince people that not all rhododendrons have a big full truss in the shape of a ball but many have loose trumpets in curtains of bloom instead.

Rhododendrons are one of the backbones of our garden and we wouldn’t have it any other way. While they have a relatively short season in full bloom, the anticipation of fattening buds stretches out the weeks with the promise of delights to come. They are as fine a shrub as any we grow here and a great deal more spectacular than most.

The nuttalliis! Oh the nuttalliis!

The nuttalliis! Oh the nuttalliis!

The nuttalliis. Oh the nuttalliis. Peak nuttallii season doesn’t start until closer to the end of the month, taking us into November but some varieties have already done their dash for this year. If we could grow only one type of rhododendron, we’d choose a nuttallii and even more specifically, the sino nuttallii from China. You can keep your big red rhodos (most people’s favourite pick). We love the fragrant, long, white trumpets which look as if they are made from waxed fabric, the lovely peeling bark and the heavy textured foliage. These are rarely offered commercially now so grab one if you ever find it for sale.

Thrips!

Thrips!

It is, by the way, nasty little leaf-sucking thrips that turn foliage silver and no, you can never turn those silver leaves green again. If you look at the underside of the leaf, you can see dark thread-like marks – these are the critters that do the damage. All you can do is to try and prevent the new season’s growth from getting similarly infested. We are not at all keen on spraying insecticide these days and you need a systemic insecticide that the plant absorbs into its system to get a thorough kill. If you must go down this path, spray in mid November, early January and late February for maximum effect. Others praise Neem oil instead but we haven’t tried it.

We favour choosing more thrip-resistant varieties, keeping them growing strongly and opening up around them to let more air and light in. Thrips prefer shade and shelter. Unless it is really
special, if it is badly thrip-prone, we replace it with a better variety. Not every plant is precious.

In the longer term, plants come and go in the fashion stakes. Goodness, even red hot pokers are having a resurgence of popularity. We don’t worry about the fashion status of the rhododendron and Mark continues hybridising for better performing cultivars. If there is no commercial market for the results, it doesn’t matter. We will continue to enjoy them in our own garden.

First published in the New Zealand Gardener and reprinted here with their permission.

Rhododendron Barbara Jury - one of Felix's  hybrids

Rhododendron Barbara Jury – one of Felix’s hybrids

Plant Collector: Rhododendron sino nuttallii

Just beautiful - R. sino nuttallii

Just beautiful – R. sino nuttallii

Oh my, but we are besotted with the nuttallii rhododendrons which flower on even as November draws into December. We would rate these in the elite class as far as rhododendrons go. Not only are the heavy, waxy trumpets large and showy, they are also very fragrant. This one is planted on a bank which was a good decision because we can look down on it and the scent wafts up. Some of the others here are several metres above nose and eye level so the scent is a bit academic because they are best viewed from afar.

The foliage is large and heavily textured (bullate for the botanical or like heavy seersucker for those of a sewing disposition) and over time the main stems develop beautiful shiny, peeling bark in a cinnamon colour. These are large and open growing shrubs so do not fit the tight and tidy mould preferred by some.

‘Sino’ just means it is the Chinese form of the species, as opposed to R. nuttallii which is found in Tibet, North Burma and northern India. The Chinese form is bigger and showier and more sensitive to cold temperatures. These plants are rarely offered for sale though you can sometimes find some of the hybrids that have been bred from them.

Rhododendron sino nuttallii

Rhododendron sino nuttallii

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

Meet the maddenii rhododendrons

The Rolls Royce of rhododendrons - sino nuttallii

The Rolls Royce of rhododendrons – sino nuttallii

Allow me to introduce you to maddenii rhododendrons. We are pretty keen on them here, although you may not share our enthusiasm if you think all rhododendrons should have the tight ball truss of blooms which is usually regarded as typical of the family. Maddenias don’t hold their flowers in that style.

But the family does include the spectacular nuttalliis with their huge trumpets. I rate these as the most stunning rhododendrons of all with their flowers which look as if they have been cast out of wax and their wonderful, big leaves which are heavily veined – described as bullate foliage. There is nothing quite like them but they are not generally available on the market. They don’t produce much cutting material and they are not easy to propagate but many will set seed so, if you are really keen, you could try raising seed. Some of the hybrids can be found from time to time – Mi Amor and Floral Sun in particular.

There are two huge pluses for the maddeniis. Most are scented, some strongly so. R. polyandrum can waft out for a metre or two which is an indication of a strong scent. Many will pass the 30cm sniff test which is good. And if you are willing to risk the pollen on the nose, most have a sweet scent when you bury your face in the flower.

The second big bonus is that the maddeniis show much better resistance to thrips than most other rhododendrons. Thrips are nasty sucking insects that hide away beneath the leaves, sucking out the chlorophyll. This turns the leaves silver and once that has happened, they can never be turned green again though the new season’s growth will be green, at least until the thrips get hold. Over time, serious infestations can weaken a plant past the point of return. Very cold winters will kill the bugs off, but we don’t get cold enough here so there is not a whole lot one can do beyond spraying with insecticide or neem oil, or trying a cloth collar soaked in systemic insecticide wrapped around the main trunk. Or you can choose varieties which are more resistant.

Bernice, as red as the maddeniis get

Bernice, as red as the maddeniis get

There is a preponderance of whites and pastels in the maddeniis and where there are coloured ones, they lean to the subtler, softer shades. In other words, there are no pure reds, purples, blues or oranges. We don’t mind because we can get the stronger colours in azaleas and other types of rhododendrons. Some of the hybrids flower so heavily that it can be like viewing a wall of bloom with barely any foliage visible at all.

Wonderful peeling bark and bullate foliage

Wonderful peeling bark and bullate foliage

I should perhaps mention also that most of Maddenia types don’t make tidy compact little buns of bushes either. They are inclined to be more open in their growth – though by no means are all of them giants. Some can only be described as leggy, but all is forgiven when they flower. Besides, another attractive feature of these rhododendrons is the lovely peeling cinnamon bark many have. If they were bushy, dense plants, you would never see it.

Google tells me that this group were first introduced to the West in 1849 by famous plant collector Joseph Hooker – he who also visited New Zealand. For reasons which are not entirely clear, he named them after Lieutenant Colonel E Madden of the Bengal Civil Service. How random is that? Given that these rhododendrons are found in northern India, Burma, southern China and the milder areas of Tibet, maybe Lt.-Col. Madden was particularly helpful to Hooker’s expeditions.

Internationally the maddeniis are rated as subtropical and somewhat tender so they are the envy of gardeners from cold climates. Our climate in New Zealand is so temperate that you are able to grow most of the maddeniis in all but the coldest, inland conditions. They form the backbone of the rhododendron collection in our garden and, being later flowering than many others, are coming into bloom right now.

There is no simple way to determine which rhododendrons fall into the maddenii group. That is what books and Google are for. But ones you may find, or know of, include Fragrantissima, Elsie Frye, Princess Alice, Bernice, Moon Orchid, the aforementioned Mi Amor and the plant confusingly known simply as Rhododendron maddenii.

The problem is sourcing these rhododendrons. In fact the problem is sourcing any interesting rhododendrons at all in these days when specialist nurseries have fallen like flies. The best option for Waikato readers may be Rhodohill or Tikitere Nurseries in Rotorua. Failing that, try Trade Me where there is a South Island grower, RhodoDirect, producing and selling by mail order. I have seen them listing the lovely Floral Sun and there are other maddeniis in their range.

Our very own Floral Sun

Our very own Floral Sun

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