Growing roses from seed can be challenging, as most seeds you get often don't germinate, no matter how much effort you put in. Fortunately, most rose plants can produce a large number of seeds in their fruit, so a high success rate is often not necessary for growing them. Keep in mind that the growing plant may have a different appearance or character from the parent plant, especially if it is the result of a cross between two different varieties.
Step
Part 1 of 3: Harvesting Seeds
Step 1. Let the roses grow by ignoring the dead flowers on your plants
Fertilization of flowers is usually assisted by insects, or occurs spontaneously in some flower varieties, so you don't need to assist fertilization by hand unless you are crossing a particular variety. Leave flowers on your plants, don't cut them. After shriveling, a small fruit which is a rose fruit will appear there.
Notes: The seeds you harvest may grow into plants with different characteristics. This can happen if you harvest seeds from a rose from a cross, or if the flower is fertilized by pollen from a different variety of roses nearby.
Step 2. Pick the roses when they are ripe
Rose fruit is initially small and green, then changes color as it grows to red, orange, brown, or purple. You can pick them at this point, or wait for them to dry and shrivel. However, don't wait until it's completely dry and browned, as the seeds inside may have died at this point.
Step 3. Open the rose fruit and remove the seeds
Open the rose fruit with a knife, so that the seeds are visible. Pull out the rose seeds with the tip of a knife or other utensil.
The number of seeds in each rose varies greatly among rose varieties. There may only be a few seeds or a few dozen seeds in the fruit
Step 4. Remove the flesh from the seeds
If the pulp remains on the surface of the seeds, this can prevent them from germinating. A quick way to get rid of them is to place the seeds in a sieve or sieve and run water over them, scrubbing the surface.
Part 2 of 3: Sowing Seeds
Step 1. Soak the seeds in a hydrogen peroxide solution (optional)
A mixture of water and hydrogen peroxide can reduce mold growth on seeds. Stir 1.5 teaspoons (7 ml) of 3% hydrogen peroxide into 1 cup (240 ml) of water. Let the rose seeds soak in this solution for at least an hour.
- Some studies suggest that a little mold growth can actually help break the shell that surrounds the seeds, but this soaking step is still recommended to prevent the growth of large amounts of mold.
- Applying a small amount of plant antifungal powder is another option to replace this step.
Step 2. Place the seeds in a damp material
Rose seeds usually will not germinate except in a cold, wet environment, such as winter. Place the seeds between two layers of damp paper towels, or in a container filled with moist salt-free river sand, peat, or vermiculite.
This is the first step in a process known as "stratification". If you're using seeds that you bought at a plant store, and the label says they're "stratified," skip this step, and move on to the seed planting section below
Step 3. Store the seeds in the refrigerator for a few weeks
Place the seeds and damp material in a plastic bag or seedling tray, and store them in a cool place in the refrigerator, such as an empty vegetable drawer.
Do not store them together with fruit or vegetables, which can release sprout-inhibiting chemicals
Step 4. Keep the seedling medium slightly moist
Check at least once or twice a week to see if the sprouts have sprouted from inside the seed. Apply a few drops of water to each sheet of paper towel that starts to dry out. Rose sprouts can take anywhere from four to sixteen weeks to grow, depending on the rose variety and the individual seeds. Often, 70% or even more rose seeds don't germinate at all.
Part 3 of 3: Planting Seeds
Step 1. Fill the container with sterile seed growth medium
A small seedling tray can make it easier for you to care for many seeds at once. Alternatively, use a plastic drink cup with a hole in the bottom, so that root growth is easier to observe.
Plain soil is not recommended in this step, as it may not drain enough water and cause the seeds to rot
Step 2. Plant the rose seeds
Some seeds available at plant stores can be planted right away. If you are sowing rose seeds as described above, plant them as soon as they begin to germinate. Plant with the sprouts pointing downwards, as these are the roots of the plant. Cover gently with soil, to a depth of about 6 mm. Leave a distance of at least 5 cm between each seed to reduce competition for plant growth.
Germinated seeds should look like young plants in a few weeks. Seeds available in plant stores do not require "stratification" at home which can take several weeks. Seeds that have not been "stratified", with the seeding process as above, may take up to two or three years to germinate
Step 3. Plant the germinated seeds in warm, moist, but not soggy soil
Temperatures between 16 – 21ºC are ideal for most rose varieties. These young plants usually do well in six hours of daily sun, but it's best to research the parent rose variety to get a clearer picture of this.
Step 4. Find out the right time to transplant young plants
The two visible leaves are usually cotyledons, or seed leaves. Once your young plants grow "true leaves", with a more similar appearance to the leaves of a regular rose, the chances of these plants surviving after transplanting will be greater. Plant transplanting is also easiest during winter or early spring, not at the height of the growing season.
- It may be best if you remove these young plants immediately if the roots become tangled in the container.
- Do not move young plants outside until the last frost of winter.
Step 5. Transfer to a larger pot or outside
When you decide to transplant a plant, wait until the weather is cool, or cloudy, or dusk, when the plant loses less water. Moisten the seeds to retain the soil around them. Dig a hole in a new place, large enough for the roots of the plant, then remove any lumps of soil from around the plant. Move this lump of earth to a new place, filling the hole with planting media if your garden soil is not enough to support the growth of roses. Water the soil after transplanting the plant.
Try planting according to the previous soil height. Do not bury the stems of plants that previously grew above the ground
Step 6. Take care of your rose plants
Once the transplanted plant looks healthy again, you can water it as usual. Applying fertilizer several times during the warm season can help your plant grow and bloom if you follow fertilization guidelines. But keep in mind that some varieties of roses will not bloom at all during their first year.
