Growing roses from seed is a low-cost and rewarding method of propagating favorite roses, but it will take two to three years for such a rose to be ready for the garden. In addition, rose seeds need to be properly cleaned and prepared before planting to increase the odds of successful germination.
Harvest rose seeds from mature and ripe rose hips that are swollen, deep in color and give slightly when pressed. Cut the hips off the bush. To begin the planting process immediately, cut the hips in half and scoop seeds and pulp into the strainer. To store, place the whole hips in the refrigerator for up to several weeks.
Separate the seeds from the flesh and pulp. Rinse the seeds in the strainer with distilled or bottled water to remove some of the flesh. Wash the seeds with a cup of the water mixed with a few drops of household bleach and abrade against the mesh to remove more flesh from the seeds. Rinse again with the distilled or bottled water.
Plant the seeds in fresh and sterile seed-starting potting mix in either nursery pots or a seed tray. Bury the seeds one-half inch to 1-inch deep and water until the soil is thoroughly moist.
Tent the pots or tray with clear plastic sheeting or a bag that can be sealed to create a greenhouse effect. Place the sealed pot or tray into the refrigerator for two to three months to cold stratify the seeds. Check periodically to add water, as needed, to make sure the soil does not dry out.
Transition the seeds between their dormancy and growth periods. Place the pot or seed tray in a location that receives bright sun and has an ambient temperature hovering around 70-degrees Fahrenheit. Slowly loosen and remove the plastic cover over a period of a week to acclimate the seeds, keeping the soil moist but not wet.
Feed twice a month with a water soluble general purpose fertilizer diluted to 50 percent of the recommended strength.
Transplant seedlings to larger individual pots when they reach 2 to 3 inches in height. Use a clean spoon to transplant the rose plants into fresh sterile medium in new pots. Water well at the time of transplant and resume the regular feeding schedule.