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.
The rose seeds can be planted right away if you have harvested them as late as November, December or January (in Southern California) or early spring after danger of frosts in your area. Place the rose seeds about one-half inch deep in a very light mixture of 50% sterile potting soil and 50% vermiculite. Some rose hybridizers use Sunshine Mix #4. You can use small pots or shallow trays to plant your seeds, whatever works for the space you have, as long as they have good drainage. Nursery flats work well for this. Lightly dust the rose seeds with RooTone or Captan before covering with soil. And then dust the top of the soil again, which will hopefully help to prevent damp-off (a disease which kills young rose seedlings). Amateur rose hybridizers concerned with toxic chemicals may want to periodically spray the seed tray with diluted peroxide and water instead of the more toxic Captan.
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.
Chilling your seeds in a refrigerator for about six to ten weeks encourages them to germinate faster once planted. However, you must take care to avoid keeping them cold for long as they can germinate while still in the refrigerator. Place your seeds on a paper towel before moistening them. Use half purified water and half peroxide to prevent the growth of mould. You can then place them in a plastic zippered bag, mark the date and variety before placing in a refrigerator set at 1 to 3 degrees C. The paper towel should remain moist for the entire period. You can check occasionally to see if it needs remoistening. Make sure you don’t freeze the towel.
NOTE: During my move, I had cut several rose branches and placed them in a grocery paper bag in my garage--only to have forgotten to bring them home for a week. The branches had been in a broiling hot enclosed garage without water, and needless to say, they looked pretty dried out to a crisp. But I didn't want to just toss them out yet (these were the climbing Charisma roses), so I got an empty plastic detergent tub and completely immersed the stems for 2 weeks (no changing water). Then I stuck them into soil and hoped for the best. Well, I got about a 50% survival rate.
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.
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.
America's most popular flower is also one of the very oldest flowers in cultivation. There are over 2,000 different rose varieties to lure us with their history and fragrance. This is because the rose, like the orchid, cross-breeds readily—a trait exploited first by nature, and then by horticulturalists. Today, we can choose from old-fashioned favorites, as well as modern varieties that are the result of intensive breeding programs throughout the world. The rose is a flower with a rich past, and an exciting future.
To plant in a garden, choose a spot with bright but indirect light, so cuttings won't be stressed by too much sun or heat. Northern and eastern exposures are perfect rooting spots. Cultivate the soil in your new propagation bed about 4 to 6 inches deep, so it crumbles easily. If your soil is heavy, incorporate a small amount of sand, so that new roots can penetrate without much effort.
I would definitely mix in some compost with your garden soil as this will improve the structure of it. The dusting with fungicide is useful as it prevents the risk of infection, however, if you keep an eye on them and be ready to spring into action then it could be worth trying without . As for planting, I would personally keep them inside for a while, give them a chance to strengthen up before putting them outside in the elements!
Selecting a disease-resistant rose is the single most effective way to avoid problems and the need for chemicals. You might start by considering some of the old rose varieties, many of which have natural disease resistance. You can also look to many of the modern roses, which are now being bred for improved disease resistance. Hybrid teas are notoriously disease-prone, and seem to lure every insect pest from miles around. They can be difficult to grow without an arsenal of chemical dusts and sprays.
Grandma's Mason Jar: For the beginner this is probably the easiest way to take rose cuttings. Not much equipment is needed, just a clear quart-size glass jar and some cuttings from your favorite rose. For you modern sodapop lovers, a 2-liter plastic bottle with the bottom cut off will work just as well. Cut a piece of rose stem about 6 inches long, remove the bottom set of leaves, and just stick the stem into the ground (or into a pot) a couple inches deep, and cover with a jar or bottle. You will need to periodically water the soil around the jar, otherwise the rose stem will dry out. It will take a couple of months for the rose stem to take root and begin leafing out with its new growth. The best time of year is spring or early fall. If you live in a mild climate, then winter and summer can also be successful for rooting roses. Intense summer heat of 100 degrees is not conducive for taking rose cuttings, nor are 32 degree or below winters.
Some people don't bother to take the time to do this, but others do. While the rose seeds are soaking, you will see that some sink to the bottom and some float on the top. The seeds that float are sometimes not viable, so you might want to throw them away. The rose seeds that sink are said to be the good ones, and are the ones to plant. There are pros and cons to this theory, and many rose hybridizers simply plant all the rose seeds that are harvested.
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.