Candy Oh rose is a plant of many names: Zlemartincipar is the cultivar name, but you are more likely to encounter the plant under some combination of the following names: Oso Happy, Candy Oh! (the exclamation point is part of the name, but it is commonly dropped), and Vivid Red. Together, “Candy Oh!” and “Vivid Red” make up the trademark name of these fast-growing roses. The explanation of this trademark name comes courtesy of Tim Wood, product development manager at Spring Meadow Nursery and Proven Winners. The “Vivid Red” part is clear enough, referring to floral color. As for “Candy Oh!,” it seems to be an amalgam of two things: For Wood, the color of the flowers is reminiscent of “a red car paint color called Candy Apple Red.” Meanwhile “Candy-O” is the name of a song sung by the American rock band, The Cars. The origins of plant names are not always apparent—and the origin of the cultivar name, Zlemartincipar, is particularly obscure. We owe the explanation of its origin to none other than the breeder of Rosa Zlemartincipar, David Charles Zlesak. The middle and last parts of the name honor Dr. Martin Cipar, a potato breeder for Frito Lay. The first three letters refer to the breeder’s own name, Zlesak. The single, pinkish-red flowers are only about 1-inch in diameter, but they occur in showy clusters. The flowers look best when they first open because they display a prominent yellow center at that time; later, this yellow color fades. Some growers describe the flowers as mildly fragrant, but many grow this bush strictly for its looks and low maintenance, not the smell of its blooms. Candy Oh roses have an upright growth habit. The growth is dense. Leaf color is a medium green. It is the ideal low-maintenance plant because it is cold-hardy and disease-resistant.

Light

Grow this landscape rose where it will receive full sunshine.

Soil

Plant Candy Oh roses where the ground in your garden is well-draining.

Water

Some growers report that Candy Oh requires quite a bit of water, but most in the North do not find this to be the case. Those who live in the South will, however, need to irrigate regularly. Watering at the base of the plant is preferred over watering from above; the latter moistens the foliage, which can invite diseases such as powdery mildew. It is also best to water in the morning so that the area has all day to dry out (rather than providing the wet conditions overnight that fungus craves).​

Temperature and Humidity

Candy Oh is quite hardy, temperature-wise, but needs good air circulation to continue healthy growth. If you live in a colder zone, your rose’s crown might need mulch in the winter to keep the roots safe from the cold weather.

Fertilizer

Amend the soil where your Candy Oh roses are with compost.

Pruning

Pruning is not required, but you can prune if you wish to keep them within bounds or to shape them. As vigorous as they are, these landscape roses are not fussy as to when they are pruned, but many growers choose to do the job in late winter or early spring since these are shrubs that bloom on new growth. Wear gloves as protection against the bush’s thorns when pruning. Some growers simply prune them whenever their thorns make it uncomfortable for them to access and care for surrounding plants. 

Overwintering

Overwintering Candy Oh roses begins in the summer, by deadheading final blooms and stopping fertilizing. Clear away dead leaves, then loosely tie the rose shrub together with jute or other natural string. Surround the base with soil, mulch, compost or leaves, to keep your plant healthy in the winter months. Come spring, you can rake this away.

Common Pests & Diseases

These roses are considered resistant to many diseases, but they are not immune to them. Such diseases include mildews, rust, and leaf spot. Make sure there is enough space between the bushes and other plants to promote good air circulation, thereby decreasing susceptibility to such diseases. You might have to spray neem oil on these shrubs to kill aphids. But the health of Candy Oh roses does not seem to suffer from aphid infestations as much as some plants do. Other pests that can attack landscape roses include beetles, borers, scale, thrips, midges, leafhoppers, and spider mites. These can be easily taken care of with insecticidal soap.