The rose tree or rose standard is an eye-catching horticultural contrivance. According to Rose Magazine, rose trees consist of at least three parts grafted together: a hardy rose rootstock, a rose cane to serve as the trunk and a showy hybrid rose on the top. To ensure the best show, the hybrid rose should be disease resistant, hardy and a re-bloomer. Tree roses are vulnerable to cold temperatures, especially at the graft areas known as bud unions. Winter protection involves laying the plant on its side in a trench and mulching with leaves. Staking is often necessary to support the fragile trunk. Despite the extra work, tree roses will always capture attention, whether in a rose garden or as a focal point on a patio.
Rose trees that measure 36 inches or more from soil level to the top of the trunk are classified as standards. Although harder to find commercially, some rose trees may reach 48 to 60 inches. Growquest, a California nursery, recommends adding 2 feet to the trunk measurement to estimate total height. The hybrid rose grafted to the top of the trunk may be a shrub rose, a grandiflora type, floribunda, hybrid tea or a miniature rose. Iceberg, Bonica, the patented Knock-Out rose series and the Betty Boop floribunda are varieties that work well in the rose tree form.
A miniature rose tree is a standard rose that is only 18 inches tall. Weeks Roses, a wholesale rose grower, uses miniature roses such as Gourmet Popcorn and the yellow and pink Rainbow's End for this type of tree rose. Christian Bedard, a hybridizer at Weeks Roses, recommends using miniature rose trees in rock gardens and for a spot of color in small spaces.
Patio rose trees are standards that are 24 inches tall. Weeks Roses uses floribunda and shrub rose varieties such as the red shrub rose Home Run and the yellow floribunda Julia Child for their patio trees. As the name suggests, patio rose trees are great for patios and other limited spaces.
Weeping rose trees are 4- to 6-foot standard forms grafted with a spreading ground cover rose such as the Red Meideland rose or the deep pink China Doll. Climbing roses such as the pink Renae take the cascade one step further, often draping close to the ground. Rose trees of 48 and 60 inches are used for this purpose.
Growers graft two similar rose varieties on a single 36-inch trunk to achieve a bi-color affect. The white shrub rose Iceberg and the Brilliant Pink Iceberg on a single stem is an example of such a pairing. Extra staking of the slender trunk is required to support the weight of two grafted roses.
Double-decker rose trees are standards with 2 roses of the same variety grafted one above the other to create a full, cascading effect. The double-decker may have several inches of space between the two hybrid rose grafts, too. Height is usually 48 inches. This type of rose tree will need extra staking for support.
Star Roses, a brand of roses from the wholesale nursery Conard-Pyle, has a pom-pom-style rose tree. According to the catalog, growers use miniature roses such as the pink Sonia Sunblaze grafted on to a 48-inch stem.
The Polar Joy rose tree is a new variety that is hardy enough on its own without needing a rootstock or trunk from other roses, according to Midwest Gardening Tips.com.