Right rose, right place: The success of the ubiquitous ‘Iceberg’ rose

For The Union-Tribune

Roses declare themselves in gardens in BIG LETTERS. They can’t help it. It is in their DNA. There are very few plain vanilla roses. But don’t ever underestimate the power of vanilla. It can be a best seller and an all-time favorite.

German hybridizer Kordes crossed the red hybrid musk rose, ‘Robin Hood’ (1927) developed by Joseph Pemberton in England, and the white hybrid tea, ‘Virgo’ (1927), bred in France by Charles Mallein. The cross produced Rosa ‘KORbin’, a very healthy floriferous floribunda that bloomed in large clusters of medium-size lightly double, white flowers. In 1958, this rose was introduced to the world. It is known as ‘Iceberg’ in the USA, ‘Schneewittchen (Snow White)’ in Germany and ‘Fée des Neiges (Snow Fairy)’ in France. Six decades later, it has not dwindled in popularity.

Why is ‘Iceberg’ so popular?

‘Iceberg’ is not a flashy rose, but it stormed the rose world nonetheless with its versatility, resilience, ever-blooming nature and disease resistance. It is the most easily recognizable and the most widely grown rose in the world. It is rated 8.4 in the American Rose Society’s “Handbook for Selecting Roses.” In 1958, it was awarded a Royal National Society Gold medal and, in 1983, ‘Iceberg’ received the “Most Favorite Rose” designation from the World Federation of Rose Societies, earning a place in their Rose Hall of Fame.

The secret to its success is simple. In the right place, ‘Iceberg’ is the right rose. It is a low-maintenance, beautiful white rose that blooms abundantly. It repeat-flowers prolifically and continuously in warm climates for nine months, taking a break only when it is pruned. It grows well in USDA zones 4b and warmer, which means that it can tolerate temperatures down to minus 20 degrees, and it can thrive in very hot temperatures as well. The blooms are produced in clusters of medium-size, double blooms with 20 to 40 petals. The buds sometimes have a slight pink tint and are long and pointed. The leaves are medium to light green and glossy. The rose has few prickles, and the mild fragrance is that of fruit and honey.

Seeing ‘Iceberg’ so ubiquitously may make it seem boring, but as a landscape plant that can bloom continuously for many, many months, ‘Iceberg’ is a winner. In addition, University of California Davis has included ‘Iceberg’ as an Arboretum All-Star performer for low water use. That is a hard act for non-rose landscape plants to beat!

For the beginner rosarian, the homeowner with little time to spare in the garden, and for the commercial landscape, ‘Iceberg’ is often a really good choice. The bushes are often mass planted as hedges or to enhance home sidewalks and walkways, commercial landscaping, golf courses, hotel landscapes and strip malls. The bushy, upright shrubs grow between 3 to 5 feet tall and 2 to 3 feet wide, which can make a stunning display when they are planted side by side, as white blooms can add elegance and formality and impart calm and tranquility. Additionally, white has great versatility and compatibility with other colors.

Nature versus nurture

‘Iceberg’ roses can look very beautiful in landscapes, but when they are grown poorly, they can be an eyesore. The downfall in the latter situation is not a strike against the rose so much as a strike against the gardeners who assume that “easy-care roses” just don’t need good rose care.

All roses need good rose culture

Like all roses, ‘Iceberg’ roses do best when they receive good rose culture. They need to be planted in the sun in a well-amended soil. They need to be adequately spaced, and they should be annually pruned. But many landscapers push the envelope and plant ‘Iceberg’ roses in partial shade, or under trees, where they will not bloom as well. They also plant these roses too close together, which hampers air circulation and is a recipe for fungal diseases.

Under these environmental conditions, ‘Iceberg’ roses can be susceptible to powdery mildew on the new leaves and bloom peduncles, and in some regions, they may also be prone to black spot, as well as ghost spotting, which are the pink spots we sometimes see on the petals.

Many of you remember Dick Streeper, the late master rosarian and founder of the Inez Grant Parker Memorial Rose Garden in Balboa Park. Dick Streeper was affectionately known as the “Rose Man” in San Diego and he wrote the rose care column for The San Diego Union-Tribune for many, many years. I approached Dick after one of his rose care presentations when I first started growing roses. I wanted to know if I had to prune my ‘Iceberg’ rose. I told him it didn’t look like it needed pruning since it was looking great, and it was covered in blooms. Without hesitation, Dick told me to cut the blooms and enjoy them in a vase indoors, and to prune the rose. And of course, he was right.

We prune ‘Iceberg’ roses like all our other floribunda roses

When we prune roses, we take out all dead, damaged and crossing canes using a pruning saw or loppers. We take these canes out right down at the bud union. This makes room for the growth of new canes, which are more productive. We keep all the youngest and strongest canes, and we cut out all thin, spindly twiggy top growth. ‘Iceberg’ is a floribunda rose, so we take about one-fourth off the height of the rose.

Having figured out approximately how much to cut off, we make each cut at an outward-facing bud eye about one-quarter inch above a leaf with five leaflets. Choosing an outward-facing bud eye prompts the rose to grow in that outward direction and away from its center, which is so important to facilitate air circulation and lessen disease. When we are finished pruning the rose, we strip off all the remaining leaves on the bush and pick up all dropped petals and leaves around the plant. The rose now has a good, healthy start to the new growing year and the pruned canes will support the growth of larger blooms and clusters of blooms. Cutting out the previous year’s diseased and pest-infested leaves and blooms minimizes fungal pathogens like powdery mildew, ghost spotting and black spot in the coming year.

Doing our best to prevent pest infestations

There is no such thing as a pest-free rose, but overcrowded roses provide a perfect setting for pest infestations. The closer we plant roses, no matter the cultivar, the more pest issues we are inviting. It is just too easy for pests to move from plant to plant, nourishing themselves and increasing in population. I often notice the first indications of the presence of chilli thrips in the summer when I walk past mass plantings of ‘Iceberg’ roses. Again, it is not the rose, but the way it is being grown. A monoculture of just roses is a recipe for pest and disease problems.

For gardeners who want to keep the planting bed all white, adding white companion plantings like sweet alyssum, nemesia or daisies maintains the color scheme and helps provide diverse plantings to attract beneficial insects into the garden to help with pest problems.

‘Iceberg’ and its ‘sports’

‘Iceberg’ has several “sports,” which are naturally occurring genetic mutations that can result in changes to the plant, including producing a bloom that is a different color or form. ‘Climbing Iceberg’ is a sport that can reach up to 10 to 12 feet tall. It was introduced in 1968 in the United Kingdom. ‘Blushing Pink Iceberg’ and ‘Brilliant Pink Iceberg’ are sports of ‘Iceberg.’ The former has light, pink-blushed petals and the latter has darker pink blooms. ‘Burgundy Iceberg’ has deep purple blooms and is a sport of ‘Brilliant Pink Iceberg.’ Interestingly, I sometimes see ‘Burgundy Iceberg’ with one or more white blooms on the bush.

There was a saying my late father-in-law repeated often, and a choice he made that always puzzled me and challenged my understanding. The saying was, “Nothing succeeds like success.” And the choice? In an ice cream parlor with 31 flavors, he would unhesitatingly pick vanilla. ‘Iceberg’ is a beautiful classic rose, a performer and totally versatile in many settings. Its attributes make it a best seller and an all-time favorite, making the saying about success ring true. It is a rose that helps me finally comprehend my father-in-law’s strange saying and his “vanilla” choice.

Perwich is a member of the San Diego Rose Society, a Consulting Rosarian and a Master Gardener with UC Cooperative Extension. For more information and advice, visit rose-harmony.com.