This is my final feature written for the Weekend Gardener. However, I would urge readers to respond to their readership survey in this latest issue. They want feedback – give them your comments. Tell them what you think of the new directions they are taking. Do. Please.
First published in the Weekend Gardener and reproduced here with their permission.
Many people don’t realise that there are more scented rhododendrons beyond the well known Fragrantissimum or the Loderis, though these cultivars have certainly stood the test of time.
The early Loderi series were bred at England’s Leonardslee Gardens at the turn of last century and Fragrantissium has been around even longer. There is little to rival the Loderis even now for big, full trusses, but they are more akin to small trees than to shrubs. Added to that, they have to be grafted and there aren’t many specialist rhododendron nurseries continuing with grafting so they are not generally available on the market.
Most gardeners need plants which are more compact.
In the smaller growing, very fragrant white flushed pink class, Floral Gift is our preference. Fragrantissimum has been around since 1868 and is the best known fragrant rhododendron. It has a wonderful scent but it is a bit leggy and open and you don’t get many flowers to the truss. Its blooms are also rather soft, so it is inclined to weather mark. There are quite a few different options in this type with their scented blooms in white with a pink flush. Princess Alice, Elsie Frye and Harry Tag are all more or less similar. All are smaller growing (around a metre high) and have good scent but you need to encourage them to form a good shape by pruning and pinching out leggy growths at the right times. Our preference in that colour range is our own Floral Gift. It has a sturdier habit of growth and its large flowers are so heavily textured that it endures most bad weather without damaging the blooms.
Most of those we grow as garden plants are hybrids – crosses between different varieties of rhododendrons. There are a number of fragrant species but these are not always easy to grow. In fact many are downright difficult. But the ones which have proven their worth as garden plants for us include the following:
R. polyandrum is the fragrant parent of many hybrids and is so strongly perfumed it will stop you as you walk past with its scent hanging heavy in the air. It has enormous cream flowers with each bloom measuring at least 12cm across. The flowers are soft so weather mark easily and the plant is rather leggy and open in growth, but where space allows, it is a wonderful garden addition.
R. maddenii is hardy for New Zealand conditions and has very heavy textured flowers which feel as if they have been cast out of wax. It is usually white with a pink flush and it flowers late in the season which makes it a good choice for colder areas. It is another relatively large grower in the two metre range.
R. cubittii is a pretty, frilly pink and white with good scent. It is an excellent smaller grower to around 1.5m and will even take full sun but the downside is that it flowers early in the season. This means that in cooler areas, it needs some protection from frosts or the flower buds will freeze and fall off and it won’t be happy at all in really cold, inland areas.
R. veitchianum is even more tender. In fact it is has about the same hardiness as a vireya rhododendron which means that any frosts more than a degree or two will not only destroy the flowering but also burn the foliage. But it is a great option for warm areas of the country and it will reward you with pristine white, frilled flowers smothering the bush in early spring and good fragrance. It also has a tidy, compact habit of growth on a smaller growing plant.
FRAGRANCE AND COLOUR
While we all love the fragrance of flowers, the plants are not producing this scent to please humans. Generally it is linked to attracting the right insects for pollination. While the rhododendron relatives of deciduous azaleas and some vireyas will use both colour and scent, fragrance in rhododendrons is generally linked to white and pale colours. You won’t find big bold, full trusses of red, blue or purple rhododendrons with scent. Part of the hybridist’s quest is to try and get new varieties with combinations of desirable characteristics.
The late Felix Jury (yes, he was my father in law) set out to try and combine fragrance, colour and healthy foliage and named a series of new rhododendrons. Many of these are still available on the market today. None of them have the big full trusses of the traditional rhododendron, but they have many other aspects in their favour, including performing well in warmer climates. His R. polyandrum hybrids all have scent, though not as strong as their scented parent. They do, however, make tidier garden plants and bring more colour. These include Bernice (crimson tones), Barbara Jury (pure yellow fluted blooms), Moon Orchid (frilly apricot and yellow) and Felicity Fair (more pastel honey colours).
R. sino nuttallii (the sino just means it comes from China) is a magnificent rhododendron species with fragrant white trumpets but it is rarely available for sale. It has, however, given birth to two colourful offspring which are compact growers and much easier to produce so more widely available. Floral Dance (above) has very frilly, very fragrant, large trumpet flowers in white with a yellow throat and deep carmine blush and tips. The heavy textured dark foliage is a bonus. Floral Sun is a half sister with pretty soft golden flowers. Its fragrance is not as strong (which means getting close enough to put your nose by the flower to smell it) but the mass of pretty flowers and the tidy, compact growth make for an excellent garden plant.
Whether we ever get a big red Rubicon or a big blue Bumblebee with strong fragrance is unknown territory but it will be by the hand of the plant hybridiser, not nature, if it happens.