Roses: bare-rooted, potted or grown from cuttings
The way we buy garden roses is changing. JENNIFER STACKHOUSE examines how modern roses are propagated and sold
Traditionally, roses are sold when dormant in winter. These bare-stemmed bushes are known as bare-rooted plants. Their roots are bare of soil but protected with sawdust or sphagnum moss, and wrapped in plastic. Increasingly, though, roses are also sold year-round in containers.
The way roses are produced by nurseries is also changing. The traditional propagation method that has been used for a rose bush is a type of grafting called budding, where a small piece of a desirable variety, which is called the scion, is inserted into the stem of a vigorous rose, known as the rootstock.
Rootstock is grown from a cutting planted in soil and grown for at least six months before it is grafted in situ in the field. Once the scion begins to grow, it forms the above-ground part of the rose that produces the leaves and flowers, while the rootstock forms the base of the stem and the roots. One to two years later, in autumn, grafted rose plants are dug up from the soil. The soil is removed from their roots, and the roots and branches are pruned, ready for the bush to be packed for sale.
While this traditional grafting method is still the main propagation method used for roses, more are being produced by cutting and tissue culture (see page 28).
di erent methods
Budding roses in the field is a skilled but awkward job. With a shortage of skilled labour in Australia, many budders are brought in from overseas, usually from New Zealand. Various rose growers have developed systems to allow budders to work at ground level instead of bending over to bud each rose. These systems include budders lying on low trolleys, so they can move along the rows of roses in the field.
This complicated and time-consuming process has been the norm, as many hybrid roses are not particularly vigorous, so they need the benefit of another rose’s root system to grow strongly, cope with a range of soils and produce lots of flowers.
However, all roses can also be propagated from cuttings. In recent years, rose growers have been experimenting with cutting-grown hybrid roses produced in pots. Recent releases, including the Flower Carpet series, are cutting-grown. Easier and cheaper to produce than field-grown grafted plants, they are grown in pots and sold year round.
Not all potted roses, however, are cutting-grown. Most of those in containers in garden centres are field-grown grafted roses, transferred into pots to be sold in leaf or flower in spring and summer.
bare-rooted vs pot-grown
Bare-rooted roses are usually cheaper than the same sized grafted rose in a pot. They are also well suited to mail order sales, allowing many growers to sell roses directly to the public from autumn to winter.
Although bare-rooted roses look like a bundle of bare, thorny sticks in winter, once planted they begin to grow and flower when spring arrives. Grafting also allows many plants to be grown from a limited amount of propagating material. To grow the same number of roses from cutting requires more propagation material.
One downside of bare-rooted roses is that unless you are familiar with the variety, for example having seen it growing in a rose display garden, you have to rely on the label, or information on the rose grower’s website, to see what the rose looks like. For those who want to know what they’re buying, a potted rose in flower in a garden centre has instant appeal.
Another important downside of grafted roses may be encountered once the bush is planted in the garden. The vigorous rootstock may outgrow the grafted variety, leading to a large but unremarkable rose plant growing in your garden. One commonly used rootstock rose is a variety known as ‘Dr Huey’, which has thorny growth, light green leaves and small, double, crimson flowers in spring.
When growth appears from below the graft, which is usually below the soil, this indicates that the rose plant is stressed. Rootstock growth should always be removed as soon as it is seen. If this happens to your plant, give it more water and fertiliser to encourage more vigorous growth above the graft.
The big pluses of buying a rose in leaf in a pot are that these plants are available year round, and the overall appearance of the plant can be assessed, from its green leafy growth to the colour, shape and fragrance of the flower. As more varieties are developed that suit the cutting-grown system of production, there will be more of these potted roses available for sale at garden centres, and they may be cheaper than grafted plants in pots.
Regardless of how a rose has been propagated, they all benefit from the same care and management, particularly in their first year of growth. Smaller plants with small root systems will need careful watering.
Above Garden roses are budded onto understock (left) or cutting grown (right). Below e Flower Carpet series of roses are all cutting grown and sold in pink pots.