can someone help me. I am trying to propagate roses and planted the stems around 5 weeks ago. The stems beautifully grew leaves etc on its own but today when I took out one stem, it has only grown a callus so far. So my question is how long does it take for the roots to grow? When I started I moistened the soil a bit at that time and since then never again. Each stem is in a pot surrounded by a ziplock bag tied to it. All stems are growing leaves. Should I start watering them more often? Would that mean I have to take the bag off every time and then tie it again? Hoping to find some answers from more experienced people.
This is a fungus called black spot. Left untreated, it can cause all the leaves on your roses to turn yellow and fall off. It will also affect nearby plants, as it spreads by spores. Remove ALL INFECTED material and throw it away or burn it. Do NOT leave it on the ground as this fungus is very hardy. It can survive winter and travels very easily, even after being removed from the affected plant. Spray your plants regularly (bi-weekly) in the growing season with a good fungicide (I like the Bayer products). You can also add a little bit of dish soap and baking soda to a spray bottle with water and spray the entire plant.
Although miniature roses have always been grown on their own roots since the 1950's when they were first introduced, Ralph Moore of Sequoia Nursery in Visalia, CA, near Fresno, offered many of the larger roses on own-root along with his vast selection of minis. His Playgirl floribunda has always been sold by Ralph as own-root cuttings in 4-inch pots, as well as a good assortment of other own-root floribundas and old garden roses. Unfortunately, Mr. Moore is now deceased and his nursery is closed.
Plant the rose bush seeds approximately ¼ inch deep in a seed-planting mix in seedling trays or your own planting trays. The trays need not be more than 3 to 4 inches deep for this use. When planting rose seeds from various rose bush hips, I use a separate tray for each different group of seeds and label the trays with that rose bushes name and planting date.
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.
I too, have tried the cut rose flower method, but haven't yet been successful--perhaps because there are chemical additives that the roses have soaked up, or because there are no nodes (which are the points where new shoots grow out), or because the stems have spent much of their energy producing the flowers...BUT, perhaps if the flowers were immediately cut off and some rooting hormones applied to the bottom cut ends, that may work.
Fertilizer: Roses are heavy feeders, and will benefit from a steady supply of nitrogen, phosphorus and potassium. You can provide these nutrients with either liquid or granular fertilizers, at a ratio of approximately 5-8-5. In most cases, regular applications of compost, rotted manure, fish emulsion and seaweed extracts will provide roses with all the nutrients they need. These organic amendments also help to moderate pH imbalances and stimulate beneficial soil life. Other organic amendments favored by rose growers include greensand, black rock phosphate and alfalfa meal.