Roses can look very, very good, but when they are bad, they are horrid. You don't think I'll show you how crummy my roses can look?! Truth In Rosing is here, if only in a small way.
Roses can have wonderful foliage. Enjoy the color of the canes, the prickles and the leaves. Their complexions are as individual as the colors of my friends'. Take, for example, Dortumund's foliage and prickles. Fiercely beautiful. Here's Fortune's Double Yellow. Prickles, cane color, leaf color and shape are as much a part of the fingerprint of every rose as fragrance, flower shape and color.
Baby Faurax is a wonderful mauve polyantha. It can look like this, or it can look like this a few weeks later. Easy to fix. Deadhead.
Bonica is a generic pink shrub rose with good foliage, the spring flush covering the whole shrub. But a few weeks later, it looks like this. Same fix: deadhead.
English Garden is an Austin shrub with nice tea-scented buff flowers. If they get botrytis, they look like this, while the same day on the same plant, others look like this.
Phyllis Bide is a large rambler (except it repeats) that puts on a spring show. But after a month and a half, it's a big job to get rid of this.
Glendora is a found rose thought to be a hybrid perpetual, though it is classified as a portland. The flowers are wonderful deep rose red, but the foliage can rust.
Seen enough? The good news is that 3 of these 5 problems are easily fixed by regular deadheading and cleanup of spent flower blossoms.
That bad news is that fungal diseases like rust, powdery mildew, blackspot and especially botrytis can ruin the foliage and/or the flowers, turning a good looking rose into an eyesore. My solution: plant-disease resistant roses and follow good garden cleanup procedures... or put up with the bad foliage or spent flowers.
What makes a disease resistant rose? To me, it is more than simply not succumbing to every fungal disease. Roses go through cycles of new leaf growth and flowering, followed by petal dropping. Then new growth emerges, followed by new flowers. Almost all roses drop leaves where a new flower stem emerges. My definition of good roses means they hold onto their leaves with good color and health after they flower and only start aging the lower foliage after new growth emerges -- and even then, they don't kill off much foliage. Not-so-good roses anticipate new growth: they prepare to drop leaves below the flowers even before the flowers drop. As those leaves age and die, they begin to show fungal disease. Experiment for yourself: cut off a perfectly healthy stem off a healthy rose and stick it in the ground. It will blackspot, rust, and/or mildew before it dries up and turns crispy brown. Growth patterns are thus a factor is disease resistance.
A fastidious rosarian can anticipate some problems by careful dead-heading that includes the removal of enough leaves below the spent flowers. That means knowing beforehand which roses need to have the entire stem removed! Other roses go through an unavoidable cycle of fungal disease after flowering before new clean growth emerges. These are not so good roses. To me, disease-resistant means disease resistant during and after flowering. After all, everything looks great in the early spring when the new growth is just emerging.
A different and related question is what makes a good landscape rose. In addition to disease resistance, I am learning that several other factors matter. (1) Shape of shrub. Needs to be graceful and well-covered in foliage. Hybrid musks are invariably nice in my garden. (2) Appearance of blooms as they age. Some flowers fade to an unsightly color, grey or tan. You've seen them by the freeway. Others, especially some rose red beauties, simply turn a dark crimson, dry up, and blow away in tiny little flakes, like Eugene de Beauharnais or Chevy Chase. (3) Appearance of the stamens and sepals after petals drop. Some stamens turn from yellow to brown very quickly. Others keep the stamens in a good way after the petals drop (Mermaid and Happenstance come to mind). Some sepals remain green after both the petals and stamens disappear, leaving little green "flowers," like Marjorie Fair. (4) Self-cleaning flowers. This means the petals fade and drop cleanly, leaving few or no hips, thereby requiring little deadheading to assure repeat flowering. These are mythic beauties not found in my garden.... (5) Impression for a distance. Some roses almost disappear from a distance, while others fill up the space.
This is just my opinion, of course. There are other priorities, views and solutions.
