Water the planted rose seeds well and place them outside in direct sunlight (no need for Grow Lights). If there is still danger of frost, then you will need to place the seed trays in a protected location such as under a tree or patio. You will need to keep the rose seed trays watered and don't let them dry out. After about six weeks, or when the weather starts to warm up, the little rose seedlings will start to sprout. They will continue to sprout as long as the weather is cool, but will stop sprouting when it gets too hot.
Monitor the rose cuttings to ensure they’re hydrated and taking root. Keep an eye on the cuttings to make sure they’re never dried out, as well as to make sure the cuttings are taking root. You can test to see if the roots are growing by gently tugging on the cuttings. You should be able to feel a slight resistance after a week or 2, meaning the roots are growing well.
Roses are usually grouped into one of two broad categories: old roses and modern roses. Old roses are those varieties discovered or developed prior to the introduction of the hybrid tea rose in 1867. But like everything else in the world of roses, when it comes to determining how a particular rose should be classified, it’s not always crystal clear.
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.
Water: Roses require more water than most other landscape plantings, especially during the first year as the plant is getting its roots established. The best way to water your roses is with drip irrigation. It concentrates the water at the root zone where it is needed, and keeps the foliage dry to minimize disease problems. A good, thick layer of organic mulch will help conserve moisture, reduce weeds, and encourage healthy root growth. As the mulch breaks down, it will also add organic matter to the soil.
Allow rose hips to develop by leaving dead flowers on the plant. The flowers are typically pollinated by insects, or pollinate themselves in some varieties, so there is no need to pollinate by hand unless you are breeding specific plants together. Leave the flowers on the rose plant without cutting them. After they wither, small fruits known as rose hips will develop in their place.
Fertilizer: Roses are heavy feeders, and will benefit from a steady supply of nitrogen, phosphorus and potassium. You can provide these nutrients with either liquid or granular fertilizers, at a ratio of approximately 5-8-5. In most cases, regular applications of compost, rotted manure, fish emulsion and seaweed extracts will provide roses with all the nutrients they need. These organic amendments also help to moderate pH imbalances and stimulate beneficial soil life. Other organic amendments favored by rose growers include greensand, black rock phosphate and alfalfa meal.