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.
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.
Why choose an old-fashioned rose over a modern hybrid? Many of the old rose varieties offer more fragrance, more complex and interesting blooms, greater disease resistance, easier care and more interesting forms. But modern roses can offer all-season blooms, and a much broader range of colors and flower forms. Some are also far more cold- hardy and disease-resistant than any of the old-fashioned varieties.
Most softwood rose cuttings will root within 10 to 14 days.1 To test their progress, tug very gently on the cuttings. You'll feel a slight resistance as the new roots form and grow into the soil. A gentle fish- or kelp-based fertilizer during this time provides beneficial nutrients. Once roots are established and plants show strong new growth, you can transplant your new roses to more permanent garden homes.
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.
When you transplant your roses, be sure to dig a much bigger hole than you think you need (for most types, the planting hole should be about 15 to 18 inches wide), and add plenty of organic matter such as compost or aged manure. This will feed your plant in the years ahead. Some old-timers recommend placing a 4-inch square of gypsum wallboard and a 16-penny nail in the hole to provide calcium and iron, both appreciated by roses.
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.
Pick a sunny spot to plant your rose cuttings. Where you place your cuttings is especially important if you’re planning on growing them outdoors. Choose a spot that’s sunny but that’s not in direct sunlight — you don’t want them to dry out. Putting the rose cuttings in a pot or container is alright as well, just make sure the container is deep and wide enough for your rose cuttings to grow.
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 received some seeds as birthday present, the seller included a bonus packet of rose seeds. There’s no indication if they’ve been stratified. If I stratify them now, it will be July when they’re ready to plant. In this region (I’m ~50 miles north of Portland, Oregon)it might be mild or very hot. I’ve read that rose seed won’t sprout if it’s too hot – how well do rose seeds keep? Will they still be viable next Spring, or should i take a chance on the weather and start them now?