Roses are among the most popular flowering shrubs in America; and for good reason. The flowers are beautiful, many of them have heavenly scents and they come in almost any color imaginable. They have a wide variety of flower types with as few as five petals or as many as 30 to 40. Some of the largest flowers will yield as much as two cups of petals each, should you want to use them for potpourri or perhaps to make rose water or to strew on your loved ones! It has been reported that Cleopatra covered the floors of her palace with fresh rose petals to a depth of one half meter in order to help seduce Mark Anthony. Apparently it worked according to history. All rose flowers are edible if you should want an interesting garnish. Just cut off the white lower portion of the petal which is often bitter. I would not suggest eating store bought roses however, since they may harbor pesticide residue. Commercially grown roses usually receive lots of pesticide sprays!
Their main downside is that some types of roses are not that hardy and cannot be reliably overwintered in parts of our region. Grafted hybrid tea roses will usually survive in most of the Hudson Valley, given a little winter protection, but at the higher elevations of the Catskill Mountains and even the surrounding foothills, they often perish during a cold winter. Some local, cold country gardeners treat them as annual shrubs that they plant and enjoy for one long season and they buy new ones the following year. That notion is really not all that extravagant when you consider how many people buy chrysanthemums each fall, purported to be perennials, but usually not.
One way to deal with the hardiness factor is to grow them in containers and bring them into a warmer place for the winter. An ideal location is somewhere the temperature hovers between 20 and 40 degrees. They don’t need sunlight once they are dormant, but they might need occasional moisture over the winter if the soil dries out completely. One downside to growing them in containers is that they will be pretty limited as to how big the shrub can get. Roses grown in the ground can get pretty huge, with some climbing varieties well over 8 feet tall. As the rose ages it will also need to be repotted every few years.
In general, grafted roses, such as hybrid tea roses, are the least hardy whereas roses that are grown on their own roots, not grafted, are hardier. Grafted roses are easy to recognize by the swollen, knob like growth on the lower stem. It is important to plant them with the graft union just at soil level. If it is buried, new canes that arise from the ground might be from the rootstock and not the grafted top. This explains why a rose bush that featured large, white flowers one season, may produce small red flowers the next year. Surprisingly, the potted up mini roses that are often sold in greenhouses at holiday times are among the hardiest varieties.
Not too many years ago, roses were considered as very high maintenance plants, subject to lots of pest problems, both insects and diseases. In recent years the rose breeders have drastically improved this situation and many of the newer varieties are really quite easy to grow. They all do seem to benefit from lots of fertilizer. If you grow roses for cut flowers, or even if you are just deadheading them, (cutting off spent flowers) make sure you make the cut directly above a five lobed leaf and not a three lobed leaf. Generally, the leaf directly below the blossom is three lobed and the ones below that are five lobed.
Part of what provoked this column and the title was my observation that this has been a great growing season for a plant we call “Rose of Sharon.” This tall shrub or small tree, is not even in the rose family despite its name. It is in the hibiscus or mallow family. Sadly it is only borderline hardy and not all that reliable to flower, but when they have a good season, such as this, they are spectacular!
Finally, I cannot write a column about roses without mentioning their prickles. Most people refer to these blood letters as “thorns,” but technically they are not. Prickles are outgrowths of the epidermis and can be easily broken off (with heavy leather gloves) whereas thorns are modified branches and almost impossible to break off. So we can either bemoan the fact that roses have prickles, or celebrate the fact that prickle bushes bear roses.