Growing climbing roses from seeds can be a rewarding experience, but it requires a bit of patience and attention to detail. Stratification is a process that helps break the seed's dormancy and stimulates germination. Here's a step-by-step guide on how to grow climbing roses from seeds with stratification:
First, what is stratification?
Rose seeds typically won't sprout unless they are kept in cold, wet conditions, mimicking a winter environment. Place the seeds between two layers of lightly dampened paper towels, or in a container of dampened salt-free river sand, peat moss, or vermiculite.
Put the seeds and moist material in a plastic bag or seedling tray in a plastic bag or seedling trays, and keep them in a cold area of a refrigerator, such as an otherwise empty crisper drawer.
Wait for a period of 4 to 16 weeks until the temperature reaches approximately 70 degrees Fahrenheit in the spring or 120 days before the last frost date in the spring.
Materials needed are: Climbing rose seeds (collected from a rose hip or purchased)
- Seed starting mix or potting soil
- Seedling trays or small pots with drainage holes
- Clear plastic wrap or seedling dome
- Watering can or spray bottle
- Plastic ziplock bag
- Refrigerator
- Grow lights (optional, for starting seeds indoors)
1. Remove the seeds from the fridge. Try to do this around the time that the seeds would normally start to germinate, such as in early spring. Make sure that the environment outside of the fridge is about 70 degrees Fahrenheit. The seed will not sprout until you take them out of the fridge. Depending on the rose variety and individual seeds, the seeds could take anywhere from four to sixteen weeks to germinate. Often, 70% or more of the seeds never sprout at all.
2. Fill a container with sterile seed starting mix. Small seedling starting trays make it easy to care for many seeds at once. Alternatively, use plastic drinking cups with a hole punched in the bottom, to make root growth easier to view.
- Regular soil is not recommended, as it may not drain well enough and cause the seedlings to rot.
3. Plant the seeds. Some store-bought seeds can be planted immediately. If you germinated your own seeds as described above, plant them as soon as they begin to sprout. Plant with the sprout pointed downward, as this is the root. Lightly cover them with soil, about 1/4 inch (6 mm) deep. Space seeds at least 2 inches (5 cm) apart to minimize competition.
- Sprouted seeds should emerge as seedlings within a week. Store-bought seeds that do not require home stratification may take several weeks.
- Seeds that have not been stratified, using the germination process above, may take two or three years to emerge.
4. Keep the seedlings in warm, moist soil. Keep the soil damp, but not soggy. A temperature between 60 and 70ºF (16–21ºC) is ideal for most rose varieties. The seedlings typically thrive on six hours of sun or more each day, but you may wish to research the parent rose's variety to get a better idea of what your roses prefer.
5. Learn when it's safe to transplant seedlings. The first two leaves visible are usually "cotyledons," or seed leaves. Once the seedling grows several "true leaves," with a more typical rose leaf appearance, it is more likely to survive transplanting. It is also easier on plants if they are transplanted to a larger pot for a year or two, and then transplanted outside.
- It may be a good idea to transplant the seedlings soon if you notice the plant is root-bound, with its roots encircling the container.
- Do not transplant it outside until after the last frost.