Red Roses

Roses are a popular crop for both domestic and commercial cut flowers. Generally they are harvested and cut when in bud, and held in refrigerated conditions until ready for display at their point of sale.

In temperate climates, cut roses are often grown in glasshouses, and in warmer countries they may also be grown under cover in order to ensure that the flowers are not damaged by weather and that pests and disease control can be carried out effectively. Significant quantities are grown in some tropical countries, and these are shipped by air to markets across the world.^[6]

Hulthemia Roses

  

  

  

Roses are divided botanically into four sub-genera, with eleven main subdivisions in the subgenus Rosa. Hulthemia persica is placed in it's own subgenus, apart from the true roses, as are the subgenuses Hesperrhodos (containing R. minutifolia and R. stellata), and Platyrhodon (with one species from east Asia, R. roxburghii). Most species roses bloom just once each year in the springtime. Modern roses owe their ability to bloom repeatedly throughout the season to the China roses (Rosa chinensis). Through selective breeding, the recessive gene responsible for remontancy (continuous blooming) has been brought into modern roses. This selective process has occurred over many generations.

Hulthemia persicas, as the name suggests, originated in the area of ancient Persia, and can be found growing wild in the dry desert-like conditions of Iran and Afghanistan. There, because of its unattractive plant habit and thorny rambling branches, it is considered more of a weed than an interesting ornamental plant. Because of their similarities to roses, it was hoped that the hulthemias could be bred with roses to produce new hybrids. After a time then, just like horses were crossed with donkeys, attempts were made to cross roses with hulthemias.

Hulthemias however, as suggested above, are not true roses just like donkeys are not true horses. The hulthemias differ from roses in three very important ways: 1) they lack auricles, the little "ear-like" projections found at the base of each leaf stem where they join the cane; 2) they have simple leaves, rather than compound leaves seen in roses; and 3) they have a distinctive red blotch at the base of their petals, giving a unique red center to their blooms. It is this third characteristic that has intrigued rose breeders for more than 40 years.

Jack Harkness was the first to successfully hybridize roses with hulthemias. At first, work was very slow and like mules, the early hybrids were infertile and frequently unattractive. From his early work, Harkness ultimately released four of his hulthemia roses for introduction. Of these, ‘Tigris’ and ‘Euphrates’ were probably the most important. The other two were ‘Nigel Hawthorne’ and ‘Xerxes’. ‘Euphrates’ was a dead-end, meaning that it was completely sterile and not useful for further breeding. 'Tigris', resulted from a cross of Hulthemia persica X 'Trier', though sterile as a pollen parent, it had a low level of fertility when used as a seed parent. 'Tigris' then became the bridge for Harkness and other rose breeders to use to transfer the red blotch into roses.

During the last 10 years, the pace has quickened to get the red hulthemia blotch into roses. Several rose breeders from around the world have entered the race to produce attractive repeat blooming hulthemia roses. The most successful among this group includes Ralph Moore of the US, Chris Warner of England, Peter Ilsink of the Netherlands, and of course, the Harkness family of England. I predict that one of these men, or more probably, each of these men will have new repeat blooming hulthemia roses available for commercial introduction within the next five years.

So now, let's discuss the question of the red blotch. How is it inherited?

It appears that the "blotch" gene (or genes) is linked to genes coding for non-remontancy (that is non-repeat blooming), willowy growth, disease susceptibility and needle-like prickles. It also appears that there are several aspects of the blotch itself that may be independently coded for: blotch size and shape, blotch color, and intensity of color.

Hulthemias behave like most species roses and lack the capacity for repeat or continuous blooming. When introducing new desirable traits from non-reblooming species into modern roses, for example the hulthemia red blotch, it takes a minimum of two generations from species roses to re-establish the recessive trait for repeat blooming. 'Tigris' is once blooming and most of the seedlings coming from 'Tigris' also lack the ability to repeat bloom. These non-remontant roses can only bloom on wood from the previous year's growth. Therefore, unlike modern repeat blooming seedlings, which bloom 8 to 10 weeks after germination, 'Tigris' seedlings usually will not bloom until the second or third year after germination. This results in a very big delay in selecting the most desirable seedlings that have the best hulthemia-type red blotch. It also necessitates keeping a large number of seedlings to fully evaluate their blooming characteristics before inferior seedlings, or those with blooms lacking the blotch can be discarded. Of course those having a good blotch can then be selected. Once selected, those seedlings, if they prove to be fertile, can be used to further concentrate the genes for the red blotch in subsequent generations and combine that trait with remontancy.

Roggers Rosess

 

colour: Blush Pink

height: Average Shrub 2.5 - 5 feet (0.75 m - 1.5 m)

scent: Slight or No Scent

introduction: Pre 1700

usda zone: Zone 7 (-11ºC/12.2ºF to -16ºC/3.2ºF)

flowers: Single

repeat: Once Flowering

A large shrub rose with peeling wood and stems to 2m, with pairs of flattened thorns at the leaf bases. Leaflets 9-19, 10-25mm long, ovate-oblong or oblong, not stalked, with fine teeth, pubescent especially on the veins beneath, the rhachis pubescent. Stipules very small, glandular on the margin. Pedicels short, stout, with fine prickles. Flowers solitary on short shoots, 5-6cm across, pale pink and white from a bright pink bud. Sepals often with small appendages. Styles not exserted from the hip. Hips around 2cm across, with numerous prickles and erect, leafy and persistent sepals. In central Japan, in southern Honshu, flowering in June. This is an attractive plant, with ferny leaves and relatively large flowers produced in succession. In climates with cool summers it might grow better than R. roxburghii, which I have found very slow-growing in the hills of north Devon. It differs from Rosa roxburghii mainly in having the smaller leaflets hairy beneath. Zone 7, will survive down to s species is named after William Roxburgh (1751-1815), superintendent of Calcutta Botanic garden and Ch