Tree Roses are more properly called Rose Standards – a term believed to come from Victorian Europe when such techniques were commonly used in the rose gardens of nobles. Typically, the central cane, onto which the hybrid rose is grafted, is 32 to 36 inches long. (Miniature rose standards may be grafted onto shorter canes of about 24 inches. These are sometimes marketed as patio tree roses.)
A graft is made to a rootstock at the bottom of the central cane. Another graft is made at the top of the cane to form the hybrid. The central cane (or standard) is usually supported by a stake.
I have grown and installed many rose standards in the last 40 plus years, but quite frankly, they tend to be more trouble than they are worth in my opinion.
Here in the South, we must not only concern ourselves with the normal pests and diseases found among roses, we must also worry about strong sun and strong, desiccating winds. With standards, sunscald on canes is a very serious problem. We typically tie the support stake on the south side of the cane to help shade it from our summer sun.
In winter, we commonly cover our modern rose bud unions with mulch to protect them during hard freezes. With a rose standard, this is almost impossible unless a wire cage is created around the rose and filled with mulch or leaves during the coldest portions of winter. The alternative in northern zones is to partially uproot the rose, and lay it into a trench dug alongside the plant. The trench is subsequently filled with soil and mulch. Any time you uproot a rose, you impede its growth and place it under stress. When roses undergo stress, diseases and pests are soon to follow... meaning more pesticides and more work. Pruning is also more important when growing rose standards. As you might expect, pruning is always important when changing the natural form of any plant or tree. Improperly pruning standards not only exacerbates pests and diseases, as it does with any rose, it may also create too much top and not enough bottom – thereby snapping or cracking the central cane. On some hybrids, it may be necessary to provide two or three support stakes until such time as the central cane becomes thick enough to support the weight of the grafted rose.All of that said, rose standards can make a wonderful addition to the garden. If you are willing to spend the time with them, they can add not only color but also structure and height to your garden as well. By Mark Whitelaw, Kindly Provided by Laura Whitelaw