Tag Archives: maddenii rhododendrons

Rhododendron season – two generations of breeding

Mark’s ‘Floral Sun’ is a great performer for in our conditions

Rhododendrons have long been a part of our lives. The first ornamental plants we bought in our twenties for our first home in Dunedin were three rhododendrons, chosen with great care from a local specialist grower. They were ‘Mayday’, ‘Princess Alice’ and, obscurely, R. oreotrephes.

Mark is not exaggerating when he says he started the nursery here from one wheelbarrow up. We will give credit to his parents, Felix and Mimosa, for many things but starting the nursery was not one of them and attempts by others to credit Felix as a nurseryman never fail to irritate. The first mail order list we ever posted out in 1982 comprised fifteen rhododendrons and Magnolia Iolanthe. Five of those fifteen were first releases from his father’s breeding and the others were mostly species, including the rare R.bachii. Rhododendrons remained a key part of our mail order offering for the next 22 years, with a wide range of both species and hybrids.

Mark gathered up all the new hybrids he could find which meant a fair swag of material out of USA, very little of which thrived in our conditions. In our time, we grew all those popular varieties of their day – ‘Lems Monarch’, ‘Lems Cameo’, ‘Ostbo’s Low Yellow’, ‘Markeeta’s Prize’ and ‘Percy Wiseman’ amongst many, probably scores, of others. Very few of them are in the garden now. Most needed a colder winter and somewhat drier conditions than we could give them. They were particularly vulnerable to thrip, giving them silver leaves and weakening the plant over time because we were not prepared to routinely spray plants in the garden.

Felix’s maddeni hybrid ‘Barbara Jury’

Just another unnamed seedling from Felix’s breeding but it wasn’t that easy to sell these types of rhododendrons to customers who expected tight, ball trusses

Felix had dabbled in breeding for years and his interest in the maddeniis was because of their excellent foliage, high health performance and fragrance. He named about twelve which we released onto the market but they were always a bit of a hard item to sell because they didn’t have the full truss that most people associate with rhododendrons. No matter that they put up a wall – or maybe curtain – of gorgeous blooms, often well scented, and kept healthy foliage all year round, it took a more sophisticated gardener to appreciate their charm.

Mark’s ‘Floral Gift’ is proving to be a bit of a star over time in local gardens at least

In his turn, Mark took his paintbrush to the task of pollinating rhododendrons. He has only named four so far, three from the maddeni group and one, ‘Meadow Lemon’, with a full truss. There are more, quite a few more here but the rhododendron lost its elevated social status in the New Zealand garden. Sales declined and the earlier abundance of specialist rhododendron nurseries either changed tack or closed down. A highly competitive market became instead one of very limited supply and little specialist knowledge.

The row of latest hybrids ‘across the road’, as we say

A fair number of readers will know Our Mark. He has never let the changing market deter him and he has continued to potter away breeding rhododendrons, albeit without the sense of urgency because we don’t see any immediate commercial potential in them. He does it very quietly so when he asked me if I had seen the rhododendrons across the road (we have another block of land that is more Mark’s domain than mine), I knew he must be pleased. These were the latest lot of crosses that had hung about the nursery for a while and were finally planted out – a ragtag collection that had not received any tender, loving care and were put out into full sun in the field a year ago. They have never been sprayed or had added fertiliser so it is a regime which separates the good performers from the strugglers.

Just a few of the promising seedlings

I was impressed. I admit that I am not a huge fan of the full trusses. They are not my personal preference. But I could see the commercial appeal of these, were they presented in their pots in the garden centre, tidy little mounds in full bud and bloom. What impressed me most was the foliage. We are too well acquainted with grungy rhododendron foliage and, as our winters have become milder, the issue with thrip infestation is getting ever worse. I photographed a fine specimen at the cemetery last week – so badly thrip damaged that it was silver all over. Not a green leaf in sight. But it wasn’t a good enough photo to use.

We know plenty about grungy foliage

Look past the flower – that foliage! Grown in hard conditions and never sprayed. That foliage is a breakthrough.

To see plants growing in what are not coddled and managed conditions with perfect foliage is a joy to a gardener’s eyes. For readers with a technical interest, these are highly complex hybrids. Mark started many years ago with the red R. arboreum, ‘Sir Charles Lemon’ (for its indumentum), ‘Pink Delight’ and ‘Helene Schiffner’ and he introduced other genes from good coloured rhododendrons that did not thrive in our conditions. Because he has kept breeding with each generation of seedlings, the finer details of the genetic make-up of this latest lot is largely a mystery, even to him.

We have no plans to release any of these. Mark will no doubt carry out some propagation trials to narrow the selections down to those that root easily from cutting. Over time, we will replace some of the under-performing rhododendrons in the garden with better selections. The hybrids may just be a little legacy that he leaves to whichever child of ours eventually comes home – a collection of market-ready, high health, proven performers with commercial potential. By that stage, the rhododendron may have returned to popularity in good gardens again.  And who knows? His next generation of seedlings may be better yet.

The gorgeous nuttalliis are a favourite of mine though not a commercial viability

The big full trusses are not so much to my taste, even when it is R. macabeanum to the left. The giant pink ‘College Pink’. 

 

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.