May 21, 2011
1 - Old rose bushes at historic homes can live for a long time.
I have a Lemon Rose bush in the garden of my historic house in Silver City and the bush is perhaps as old as the house (1877). One stalk appears to be going bad. It has stunted leaves, they are yellow, and the blooms are tiny. I snapped off all the buds and wonder if I should cut the entire stalk off and apply pruning sealer to the severed limb? The branch is large, about one and one half inches in diameter. The rest of the bush appears OK, except I do notice several yellow leaf clusters. Recently a neighbor erected a wooden fence that may decrease the amount of sunlight, but I cannot see how that would be a factor since there was a large tree in the yard until the wind blew it over. That was several years ago.
I searched the internet and discovered several roses called "lemon rose", so I am not certain I know which rose you are discussing. However, a rose as old as you mentioned is not a modern hybrid tea rose. Such "old-fashioned" roses are often hardier than most modern roses. They can live a long time, but their old canes (stems) die and are replaced by new canes that form from the base (crown) of the rose shrub. This may just be an old cane that is declining and should be replaced by a new cane. Watch for new growth sprouting from at or near the ground level. This winter's cold may have contributed to the decline of this cane. I assume there are other, more vigorous canes that will remain and feed the growth of any new canes.
Cutting the old cane near the ground can stimulate growth of new canes. However, they sometimes form without this inducement. The past winter may have damaged other canes as well (the yellow leaf clusters that you mentioned). Pruning paint is not needed following pruning, but rose growers often cover the freshly cut end of a rose cane with some casein glue (white glue or carpenters glue) to seal it and keep carpenter bees from mining the pith in the center of the fresh cut. The carpenter bee, if it mines the pith, can cause the cane to die back.
Pruning as usually done for hybrid roses is not needed or desired for most old-fashioned roses. However, removal of the old, declining canes is good. Adequate water and some (not much) fertilization in the early growing season should help this rose recover from the stress of a hard winter. A mulch (wood chips) over the roots in the summer will help retain moisture and protect the roots from the heat in New Mexico. This rose has survived a long time and will probably persist much longer.
You can also get help at your local NMSU County Extension Service office.
Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: firstname.lastname@example.org, office: 505-865-7340, ext. 113.
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.
Please copy your County Extension Agent and indicate your county of residence when you submit your question!