Pests and diseases: Prevention is the best way to avoid pest and disease problems. Start with disease-resistant varieties, keep plants in healthy condition (well fertilized and well watered), maintain good air circulation, keep foliage dry, and remove any diseased foliage or spent flowers. For Japanese beetle grubs, use beneficial nematodes or Milky Spore (Bacillus popilliae). Rose Rx is effective against scale, spidermites and aphids. For more information, see the Pest and Disease Finder.
Place a jar over each cutting to form a sort of miniature greenhouse for each cutting. It is extremely important that the soil moisture for the cuttings does not dry out at this rooting time. The jar will help to hold humidity in, but can be a problem if it is subjected to a lot of hot afternoon sun, as it will overheat the cutting and kill it, thus the need for shielding against the exposure to the hot afternoon sun when you root roses. Watering of the planting site every other day may be required to keep the soil moist but do not create a standing water or muddy soils situation.
Caring for rose bushes is important to their overall health and vigor, especially when it comes to watering. Roses require at least an inch of water weekly throughout their growing season, beginning in spring or following spring planting. While overhead watering is suitable before the onset of new growth, it is often better to water these plants at the soil line using soaker hoses or similar means. Rose bushes are very susceptible to fungal diseases, such as black spot and powdery mildew, especially when their foliage is kept too wet.
Roses are usually grouped into one of two broad categories: old roses and modern roses. Old roses are those varieties discovered or developed prior to the introduction of the hybrid tea rose in 1867. But like everything else in the world of roses, when it comes to determining how a particular rose should be classified, it’s not always crystal clear.
There will be disappointments along the way, when many rose seeds fail to germinate, or perhaps they do germinate, only to die several weeks later from damp-off disease. Sometimes a rose seedling will turn out to be as ugly as sin, or very sickly, and you will reluctantly have to throw it away. Other times they will be just ho-hum, or look too much like its parent, and therefore have no value. But, just when you don't expect it, you might discover that one of your rose seedlings turns out to be very special.