The ripened rose hip is then placed on a clean cutting board and cut in half to remove the seeds. Place the seeds in a clean container. Add some diluted bleach to kill off any bacteria and fungus spores. You can make the bleach by mixing drinking water with two teaspoons of household bleach. Stir the seeds well before rinsing them and using bottled water to remove all the bleach. To further clean and disinfect the seeds, put them in the container and add some hydrogen peroxide. The seeds can be soaked for up to 24 hours before rinsing them with clean water to clear all the hydrogen peroxide.
A gentle way to clean the rose seeds is to use a Cuisinart or other brand of blender with a dough blending attachment, which is made of plastic and does not have sharp blades. You can blend the rose seeds using this gentle dough attachment for several minutes without any damage to the seeds. Do not use a blender with sharp metal blades as damage to the rose seeds may occur.
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.
The next step how to grow roses from seed is to sprout the rose seeds. After having gone through their “stratification” time, take the containers out of the refrigerator and into a warm environment of around 70 F. (21 C.). I do my best to time this for early spring when the seedlings would normally be coming out of their cold cycle (stratification) outside and starting to sprout.
Ever wonder if you could root and grow roses from a branch of your favorite rose bush? Roses actually root rather easily. However most roses are grafted onto the rootstock of a different type of rose than the top, flowering portion, so the rose you root and grow may look nothing like the rose you started with. Grafting is done to improve strength, disease resistance, or hardiness, and even if you do get something resembling the parent rose you took your cutting from, it might not have that rose's hardiness. Rooting a rose cutting may not be hard to do, but it is something of a gamble.
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.